Abstract: Stoerig and Cowey’s work is widely regarded as showing that monkeys with lesions in the primary visual cortex have blindsight. However, Mole and Kelly persuasively argue that the experimental results are compatible with an alternative hypothesis positing only a deficit in attention and perceptual working memory. I describe a revised procedure which can distinguish these hypotheses, and offer reasons for thinking that the blindsight hypothesis provides a superior explanation. The study of blindsight might contribute towards a general investigation into animal consciousness, though there is a problem when it comes to showing how a non-verbal animal can indicate whether or not it is perceiving consciously. Perhaps whether there is something that it is like to be a given animal depends on whether it exhibits the cognitive profile of conscious vision as opposed to non-conscious “natural blindsight.”

Abstract: Some patients with damaged striate cortex have blindsight-the ability to discriminate unseen stimuli in their clinically blind visual field defects when forced-choice procedures are used. Blindsight implies a sharp dissociation between visual performance and visual awareness, but signal detection theory indicates that it might be indistinguishable from the behavior of normal subjects near the lower limit of conscious vision, where the dissociations could arise trivially from using different response criteria during clinical and forced-choice tests. We tested the latter possibility with a hemianopic subject during yes-no and forced-choice detection of static and moving targets. His response criterion differed significantly between yes-no and forced-choice responding, and the difference was sufficient to produce a blindsight-like dissociation with bias-sensitive measures of performance. When measured independently of bias, his sensitivity to static targets was greater in the forced-choice than in the yes-no task (unlike normal control subjects), but his sensitivity to moving targets did not differ. Differences in response criterion could therefore account for dissociations between yes-no and forced-choice detection of motion, but not of static pattern. The results explain why patients with blindsight are apparently more often ''aware'' of moving stimuli than of static stimuli. However, they also imply that blindsight is unlike normal vision near threshold, and that pattern- and motion-detection in blindsight may depend on different sets of neural mechanisms during yes-no and forced-choice tests

Abstract: In three macaque monkeys with unilateral removal of primary visual cortex and in one unoperated monkey, we measured reaction times to a visual target that was presented at a lateral eccentricity of 20o in the normal, left, visual hemifield. When an additional stimulus was presented at the corresponding position in the right hemifield (hemianopic in three of the monkeys), it significantly slowed the reaction time to the left target if it preceded it by delays from 100-500 msec. The most effective delay depended on the particular experimental paradigm and perhaps on the experience of the monkey with the task. The results show that reaction times to seen targets in the normal hemifield of monkeys are influenced by the presentation of ''unseen'' targets in the anopic hemifield, as in some patients with cortically blind visual field defects

Abstract: Cortical color blindness, or cerebral achromatopsia, has been likened by some authors to ''blindsight'' for color or an instance of ''covert'' processing of color. Recently, it has been shown that, although such patients are unable to identify or discriminate hue differences, they nevertheless show a striking ability to process wavelength differences, which can result in preserved sensitivity to chromatic contrast and motion in equiluminant displays. Moreover, visually evoked cortical potentials can still be elicited in response to chromatic stimuli. We suggest that these demonstrations reveal intact residual processes rather than the operation of covert processes, where proficient performance is accompanied by a denial of phenomenal awareness. We sought evidence for such covert processes by conducting appropriate tests on achromatopsic subject M.S. An ''indirect'' test entailing measurement of reaction times for letter identification failed to reveal covert color processes. In contrast, in a forced choice oddity task for color, M.S. was unable to verbally indicate the position of the different color, but was surprisingly adept at making an appropriate eye movement to its location. This ''direct'' test thus revealed the possible covert use of chromatic differences

Abstract: Abstract. A rhesus monkey, Helen, from whom the striate cortex was almost totally removed, was studied intensively over a period of 8 years. During this time she regained an effective, though limited, degree of visually guided behaviour. The evidence suggests that while Helen suffered a permanent loss of `focal vision she retained (initially unexpressed) the capacity for `ambient vision

Abstract: : The work of Alan Cowey and Petra Stoerig is often taken to have shown that, following lesions analogous to those that cause blindsight in humans, there is blindsight in monkeys. The present paper reveals a problem in Cowey and Stoerig ’ s case for blindsight in monkeys. The problem is that Cowey and Stoerig ’ s results would only provide good evidence for blindsight if there is no difference between their two experimental paradigms with regard to the sorts of stimuli that are likely to come to consciousness. We show that the paradigms could differ in this respect, given the connections that have been shown to exist between working memory, perceptual load, attention, and consciousness

Abstract: Discrimination of forms defined solely by color and discrimination of hue are dissociated in cerebral achromatopsia. Both must be based on potentially explicit information derived from differentially color-sensitive photoreceptors, yet only one gives rise to phenomenal experience of color. By analogy, visual information may be used to form explicit representations for action without giving rise to any phenomenal experience other than that of making the action

Abstract: The filling-in process proposed as a cover up for the existence of the blind spot has some conceptual similarities to blindsight. The perceptual operation of a hypothetical mechanism responsible for filling in represents a logical paradox. The apparent indeterminacy of the percept in the optic-disc region can be tested experimentally by viewing the grating test pattern below

Abstract: Blindsight is the ability of patients with an impaired visual cortex to perform visually in their blind field without acknowledging that performance. This ability has been interpreted as a sign of the absence of phenomenal consciousness, and neuroscientific studies have extensively studied cases of it. Different proposals separate visual form recognition from motion perception, and attempt to show that either the former or the latter is solely responsible for blindsight performance. However, a review of current experimental evidence shows that a poor performance (on both form and motion) is accompanied by poor awareness. Blindsight cases do not influence the qualia debate, because they denote a severe visual performance deficit, and not because of a purportedly non-phenomenal nature of consciousness

Abstract: The work of Alan Cowey and Petra Stoerig is often taken to have shown that, following lesions analogous to those that cause blindsight in humans, there is blindsight in monkeys. The present paper reveals a problem in Cowey and Stoerig's case for blindsight in monkeys. The problem is that Cowey and Stoerig's results would only provide good evidence for blindsight if there is no difference between their two experimental paradigms with regard to the sorts of stimuli that are likely to come to consciousness. We show that the paradigms could differ in this respect, given the connections that have been shown to exist between working memory, perceptual load, attention, and consciousness

Abstract: Although the study of visual perception has made more progress in the past 40 years than any other area of cognitive science, there remain major disagreements as to how closely vision is tied to general cognition. This paper sets out some of the arguments for both sides (arguments from computer vision, neuroscience, Psychophysics, perceptual learning and other areas of vision science) and defends the position that an important part of visual perception, which may be called early vision or just vision, is prohibited from accessing relevant expectations, knowledge and utilities - in other words it is cognitively impenetrable. That part of vision is complex and articulated and provides a representation of the 3-D surfaces of objects sufficient to serve as an index into memory, with somewhat different outputs being made available to other systems such as those dealing with motor control. The paper also addresses certain conceptual and methodological issues, including the use of signal detection theory and event-related potentials to assess cognitive penetration of vision. A distinction is made among several stages in visual processing. These include, in addition to the inflexible early-vision stage, a pre-perceptual attention allocation stage and a post-perceptual evaluation, memory-accessing, and inference stage which provide several different highly constrained ways in which cognition can affect the outcome of visual perception. The paper discusses arguments that have been presented in both computer vision and psychology showing that vision is "intelligent" and involves elements of problem solving". It is suggested that these cases do not show cognitive penetration, but rather they show that certain natural constraints on interpretation, concerned primarily with optical and geometrical properties of the world, have been compiled into the visual system. The paper also examines a number of examples where instructions and "hints" are alleged to affect

Abstract: Some patients with a lesion to the striate cortex (V1), when assessed through forced-choice paradigms, are able to detect stimuli presented in the blind field, despite reporting a complete lack of visual experience. This phenomenon, known as blindsight, strongly implicates V1 in visual awareness. However, the view that V1 is indispensable for conscious visual perception is challenged by a recent finding that the blindsight subject GY can be aware of visual qualia in his blind field, implying that V1may not be critical under all circumstances. This apparent contradiction raises the following question: if V1 is not always necessary for phenomenal awareness, why do V1 lesions have such a detrimental effect on conscious perception? It is suggested here that this contradiction can be resolved by considering the impact of V1 lesions on the functioning of the whole visual cortex.

Abstract: GY, an extensively studied human hemianope, is aware of salient visual events in his cortically blind field but does not call this ''vision.'' To learn whether he has low-level conscious visual sensations or whether instead he has gained conscious knowledge about, or access to, visual information that does not produce a conscious phenomenal sensation, we attempted to image process a stimulus s presented to the impaired field so that when the transformed stimulus T(s) was presented to the normal hemifield it would cause a sensation similar to that caused by s in the impaired field. While degradation of contrast, spatio-temporal filtering, contrast reversal, and addition of smear and random blobs all failed to match the response to a flashed bar sf, moving textures of low contrast were accepted to match the response to a moving contrast-defined bar, sm. Orientation and motion direction discrimination of the perceptually matched stimuli [sm and T(sm)] was closely similar. We suggest that the existence of a satisfactory match indicates that GY has phenomenal vision

Abstract:   The neural substrate of early visual processing in the macaque is used as a framework to discuss recent progress towards a precise anatomical localization and understanding of the functional implications of the syndromes of blindsight, achromatopsia and akinetopsia in humans. This review is mainly concerned with how these syndromes support the principles of organization of the visual system into parallel pathways and the functional hierarchy of visual mechanisms

Abstract: The evidence of blindsight is occasionally used to argue that we can see things, and thus have perceptual belief, without the distinctive visual awareness accompanying normal sight; thereby displacing phenomenality as a component of the concept of vision. I maintain that arguments to this end typically rely on misconceptions about blindsight and almost always ignore associated visual (or visuomotor) pathologies relevant to the lessons of such cases. More specifically, I conclude, first, that the phenomena very likely do not result from dissociations within a single system, but from the interaction of evolutionarily distinct, if interacting, systems; second, that a closer study of spared motor abilities indicates that verbal responses of patients result not from degraded vision but from proprioception; and, finally, above chance verbal responses, being forced guesses, are not tentative beliefs and cannot become beliefs just by training patients to have more confidence in their responses

Abstract: within-field task as testing proceeded. (In any case, the two-field task is presumably a more difficult one than the one-field task. ...

Abstract: The extent to which visual information on the contralateral, unattended side influences the performance of patients with hemispatial neglect was studied in a visuomotor reaching task. We replicated the well-established finding that, relative to target-alone trials, normal subjects are slower to reach to targets in the presence of visual distractors which appear either ipsilateral or contralateral to the target, with greater interference in the former condition. Six patients with hemispatial neglect showed even greater interference than did the normal subjects when the distractor appeared ipsilaterally but showed no significant interference from contralateral distractors. This pattern of performance was qualitatively similar for patients with lesions restricted to posterior regions and for patients with more extensive lesions involving both posterior and anterior brain regions. These findings suggest that, in the visuomotor domain, information on the contralateral side is processed minimally, if at all, in patients with hemispatial neglect

Abstract: Ninety-one right brain-damaged patients with left neglect and 43 right brain-damaged patients without neglect were asked to extend horizontal segments, either left- or rightward, starting from their right or left endpoints, respectively. Earlier experiments based on similar tasks had shown, in left neglect patients, a tendency to overextend segments toward the left side. This seemingly paradoxical phenomenon was held to undermine current explanations of unilateral neglect. The results of the present extensive research demonstrate that contralesional overextension is also evident in most right brain-damaged patients without contralesional neglect. Furthermore, they show that in a minority of left neglect patients, the opposite behavior, i.e., right overextension can be found. The paper also reports the results of correlational analyses comprising the parameters of line-extension, line-bisection, and cancellation tasks, as well as the parameters relative to the Milner Landmark Task, by which a distinction is drawn between perceptual and response biases in unilateral neglect. A working hypothesis is then advanced about the brain dysfunction underlying neglect and an attempt is made at finding an explanation of neglect and the links between the mechanisms of space representation and consciousness through the study of the changes induced by unilateral brain lesions in the characteristics of space-coding neurons. Abbreviations: C, control group;GN+91,full group of neglect patients;GN+27,group of neglect patients with relative left overextension;GN+14,group of neglect patients with relative right overextension;GN-43,full group of non-neglect patients;GN-9,group of non-neglect patients with relative left overextension; H canc, H cancellation task; LE, left extension; LE/RE, ratio of left-right extension; N+, neglect patients; N-, non-neglect patients; PB Land-M, perceptual bias on Landmark motor task; PB Land-V, perceptual bias on Landmark verbal task; RB Land-M, response bias on Landmark motor task; RB Land-V, response bias on Landmark verbal task; RE, right extension

Abstract: O SET THE STAGE for the discussion[1], I will rehearse and clarify a well-known dispute between A. J. Ayer and J. L. Austin concerning whether perceptual judgments are inferences. Both in his Sense and Sensibilia[2] and in his "Other Minds,"[3] Austin carefully distinguishes recognizing that p from inferring that p. For the purpose of comparing his position to Ayer's, we might put his basic claim in this way: given the way words such as "recognize" and "infer" are used outside philosophical discussions, one clearly distinguishes instances of recognizing from instances of inferring. Yet Ayer does not dispute that, but replies that while non-philosophers do make a sharp distinction between the two, it is arbitrary for philosophical purposes.[4] Claims based upon one's having recognized something are sufficiently like claims based upon one's having inferred, Ayer supposes, that it is useful to treat them as instances of a common category. So the issue is not whether the distinction is recognized outside philosophical circles, but whether it is a defensible and useful one to make. Clearly, Austin insists upon the distinction because he supposes that failing to make it will promote philosophical confusion; indeed, he argues that one traditional problem of skepticism is largely due to this confusion.[5] In his "Other Minds," Austin tries to suggest how recognizing differs from inferring by showing how the sorts of questions or challenges brought to bear differ between the two sorts of claim:[6] for inferences, one wants a rehearsal of the pieces of evidence and an account of their connections to the judgment; for perceptual claims of recognition, one explores whether the observer had the opportunity to see what he claimed to have seen, whether he had acquired the expertise to recognize the sort of thing he claimed to have seen, and whether the circumstances were free of evident distraction and defect. But his readers' appreciation of these things depends

Abstract: We describe some of the signs and symptoms of left visuo-spatial neglect. This common, severe and often long-lasting impairment is the most striking consequence of right hemisphere brain damage. Patients seem to (over-)attend to the right with subsequent inability to respond to stimuli in contralesional space. We draw particular attention to how patients themselves experience neglect. Furthermore, we show that the neglect patient's loss of awareness of left space is crucial to an understanding of the condition. Even after left space has been brought into the patient's consciousness (either by local cueing on the left or by an emphasis on global properties of the scene as a whole), this awareness of left space rapidly declines. We suggest that much of the symptomology of left neglect can be interpreted as a disconnection between brain mechanisms that are relatively specialized for local (detail) visual processing and global (panoramic) processing. This failure of communication between functional (subpersonal) mechanisms then has consequences for how perceptual and representational content enters into awareness. Failure of the local contents of left space to be consciously accessed is, in turn, an important aspect of why left neglect is so difficult to remediate. Patients can ''know'' that they have neglect but are cut off from the perceptual awareness that would enable them to overcome their attentional bias to the right

Abstract: Recent studies have shown that schizophrenia may be a disease affecting the states of consciousness. The present study is aimed at investigating metamemory, i.e., the knowledge about one's own memory capabilities, in patients with schizophrenia. The accuracy of the Confidence level (CL) in the correctness of the answers provided during a recall phase, and the predictability of the Feeling of Knowing (FOK) when recall fails were measured using a task consisting of general information questions and assessing semantic memory. Nineteen outpatients were paired with 19 control subjects with respect to age, sex, and education. Results showed that patients with schizophrenia exhibited an impaired semantic memory. CL ratings as well as CL and FOK accuracy were not significantly different in the schizophrenic and the control groups. However, FOK ratings were significantly reduced for the patient group, and discordant FOK judgments were also observed more frequently. Such results suggest that FOK judgments are impaired in patients with schizophrenia, which confirms that schizophrenia is an illness characterized by an impaired conscious awareness of one's own knowledge

Abstract: Based on recent insight into the thalamocortical system and its role in perception and conscious experience, a unified pathophysiological framework for hallucinations in neurological and psychiatric conditions is proposed, which integrates previously unrelated neurobiological and psychological findings. Gamma-frequency rhythms of discharge activity from thalamic and cortical neurons are facilitated by cholinergic arousal and resonate in networks of thalamocortical circuits, thereby transiently forming assemblies of coherent gamma oscillations under constraints of afferent sensory input and prefrontal attentional mechanisms. If perception is based on synchronisation of intrinsic gamma activity in the thalamocortical system, then sensory input to specific thalamic nuclei may merely play a constraining role. Hallucinations can be regarded as underconstrained perceptions that arise when the impact of sensory input on activation of thalamocortical circuits and synchronisation of thalamocortical gamma activity is reduced. In conditions that are accompanied by hallucinations, factors such as cortical hyperexcitability, cortical attentional mechanisms, hyperarousal, increased noise in specific thalamic nuclei, and random sensory input to specific thalamic nuclei may, to a varying degree, contribute to underconstrained activation of thalamocortical circuits. The reticular thalamic nucleus plays an important role in suppressing random activity of relay cells in specific thalamic nuclei, and its dysfunction may be implicated in the biological vulnerability to hallucinations in schizophrenia. Combined with general activation during cholinergic arousal, this leads to excessive disinhibition in specific thalamic nuclei, which may allow cortical attentional mechanisms to recruit thalamic relay cells into resonant assemblies of gamma oscillations, regardless of their actual sensory input, thereby producing an underconstrained perceptual experience. Key Words: Charles Bonnet syndrome; gamma oscillations; hallucinations; late paraphrenia; Lewy body dementia; perception; schizophrenia; thalamocortical system

Abstract: Philosophers are interested in the phenomenon of thought insertion because it challenges the common assumption that one can ascribe to oneself the thoughts that one can access first-personally. In the standard philosophical analysis of thought insertion, the subject owns the ‘inserted’ thought but lacks a sense of agency towards it. In this paper we want to provide an alternative analysis of the condition, according to which subjects typically lack both ownership and authorship of the ‘inserted’ thoughts. We argue that by appealing to a failure of ownership and authorship we can describe more accurately the phenomenology of thought insertion, and distinguish it from that of non-delusional beliefs that have not been deliberated about, and of other delusions of passivity. We can also start developing a more psychologically realistic account of the relation between intentionality, rationality and self knowledge in normal and abnormal cognition

Abstract: I compare Frith and colleagues’ influential comparator account of how the sense of agency is elicited to the multifactorial weighting model advocated by Synofzik and colleagues. I defend the comparator model from the common objection that the actual sensory consequences of action are not needed to elicit the sense of agency. I examine the comparator model’s ability to explain the performance of healthy subjects and those suffering from delusions of alien control on various self-attribution tasks. It transpires that the comparator model needs case-by-case adjustment to deal with problematic data. In response to this, the multifactorial weighting model of Synofzik and colleagues is introduced. Although this model is incomplete, it is more naturally constrained by the cases that are problematic for the comparator model. However, this model may be untestable. I conclude that currently the comparator model approach has stronger support than the multifactorial weighting model approach.

Abstract: Blackwell, 2000 Review by George Graham, Ph.D on Oct 27th 2000 Volume: 4, Number: 43

Abstract: Synofzik, Vosgerau, and Newen (2008) offer a powerful explanation of the sense of agency. To argue for their model they attempt to show that one of the standard models (the comparator model) fails to explain the sense of agency and that their model offers a more general account than is aimed at by the standard model. Here I offer comment on both parts of this argument. I offer an alternative reading of some of the data they use to argue against the comparator model. I argue that contrary to Synofzik, Vosgerau and Newen’s reading the case of G.L. supports rather than contradicts the comparator model. Next I suggest how the comparator model can differentiate failures of action attribution in patients suffering parietal lobe lesions and delusions of alien control. I also argue that the apparently unexpected phenomenon of “hyperassociation” is predicted by the comparator model. Finally I suggest that as it stands Synofzik, Vosgerau and Newen’s model is not well specified enough to explain deficits in the sense of agency associated with delusions of thought insertion. Thus they have not met their second argumentative burden of showing how their model is more general than the comparator model.

Abstract: I offer an account of thought insertion based on a certain model of self-knowledge. I propose that subjects with thought insertion do not experience being committed to some of their own beliefs. A hypothesis about self-knowledge explains why. According to it, we form beliefs about our own beliefs on the basis of our evidence for them. First, I will argue that this hypothesis explains the fact that we feel committed to those beliefs which we are aware of. Then, I will point to one feature of schizophrenia that suggests that subjects with thought insertion may not be able to know their own beliefs in that way

Abstract: This article provides an introduction to a special issue of the journal Philosophy, Psychiatry and Psychology, On Understanding and Explaining Schizophrenia. The article identifies a common thread running through the different contributions to this special issue, inspired by Jaspers's (1963) suggestion that a profound impairment in the ability to engage in interpersonal and social relations is a key factor in psychiatric disorders. It is argued that this suggestion can help solve a central dilemma in psychopathology, which is to make intelligible the emergence and nature of psychiatric phenomena involving disturbances of rationality, intentionality and self-consciousness, whilst at the same time accounting for a sense in which such phenomena resist understanding.

Abstract: Empirical approaches on topics such as consciousness, self-awareness, or introspective perspective, need a conceptual framework so that the emerging, still unconnected findings can be integrated and put into perspective. We introduce a model of self-consciousness derived from phenomenology, philosophy, the cognitive, and neurosciences. We will then give an overview of research data on one particular aspect of our model, self-agency, trying to link findings from cognitive psychology and neuroscience. Finally, we will expand on pathological aspects of self-agency, and in particular on psychosis in schizophrenia. We show, that a deficient self-monitoring system underlies, in part, hallucinations and formal thought (language) disorder in schizophrenia. We argue, that self-consciousness is a valid construct and can be studied with the instruments of cognitive and neuroscience

Abstract: Schizophrenia, like other pathological conditions of mental life, has not been systematically included in the general study of consciousness. By focusing on aspects of chronic schizophrenia, we attempt to remedy this omission. Basic components of Husserl’s phenomenology (intentionality, synthesis, constitution, epoche, and unbuilding) are explicated and then employed in an account of chronic schizophrenia. In schizophrenic experience, basic constituents of reality are lost and the subject must try to explicitly re-constitute them. “Automatic mental life” is weakened such that much of the world that is normally taken-for-granted cannot continue to be so. The subject must actively re-lay the ontological foundations of reality

Abstract: This paper examines Ian Hacking's analysis of the looping effects of psychiatric classifications, focusing on his recent account of interactive and indifferent kinds. After explicating Hacking's distinction between 'interactive kinds' (human kinds) and 'indifferent kinds' (natural kinds), I argue that Hacking cannot claim that there are 'interactive and indifferent kinds,' given the way that he introduces the interactive-indifferent distinction. Hacking is also ambiguous on whether his notion of interactive and indifferent kinds is supposed to offer an account of classifications or objects of classification. I argue that these conceptual difficulties show that Hacking's account of interactive and indifferent kinds cannot be based on - and should be clearly separated from - his distinction between interactive kinds and indifferent kinds. In clarifying Hacking's account, I argue that interactive and indifferent kinds should be regarded as objects of classification (i.e., kinds of people) that can be identified with reference to a law-like biological regularity and are aware of how they are classified. Schizophrenia and depression are discussed as examples. I subsequently offer reasons for resisting Hacking's claim that the objects of classification in the human sciences - as a result of looping effects - are 'moving targets'

Abstract: This dissertation examines psychiatry from a philosophy of science perspective, focusing on issues of realism and classification. Questions addressed in the dissertation include: What evidence is there for the reality of mental disorders? Are any mental disorders natural kinds? When are disease explanations of abnormality warranted? How should mental disorders be classified? In addressing issues concerning the reality of mental disorders, I draw on the accounts of realism defended by Ian Hacking and William Wimsatt, arguing that biological research on mental disorders supports the inference that some mental disorders (e.g., schizophrenia, mood disorders, and anxiety disorders) are real theoretical entities, and that the evidence supporting this inference is causal and abductive. In explicating the nature of such entities, I argue that real mental disorders are natural kinds insofar as they are natural classes of abnormal behavior whose members share the same causal structure. I present this position in terms of Richard Boyd’s homeostatic cluster property theory of natural kinds, and argue that this perspective reveals limitations of Hacking’s account on the looping effects of human kinds, which suggests that the objects classified by psychiatrists are unstable entities. I subsequently argue that a subset of mental disorders (e.g., schizophrenia and Down syndrome) are mental illnesses insofar as they are disorders caused by a dysfunctional biological process that leads to harmful consequences for individuals. I present this analysis against Thomas Szasz’s argument that mental illness is a myth. In addressing issues of psychiatric classification, my analysis focuses on the Diagnostic and Statistical Manual of Mental Disorders (DSM), which has been published regularly by the American Psychiatric Association since 1952, and is currently in its fourth edition. After examining the history of DSM in the twentieth century, and in particular, DSM’s shift to an atheoretical and purely descriptive system in the 1980s, I consider the relative merits of descriptive versus causal systems of classification. Drawing on Carl Hempel’s analysis of taxonomic systems in psychiatry, I argue that a causal classification system would provide a superior approach to psychiatric classification than the descriptive system currently favored by DSM.

Abstract: Anosognosia is literally ‘unawareness of or failure to acknowledge one’s hemi- plegia or other disability’ (OED). Etymology would suggest the meaning ‘lack of knowledge of disease’ so that anosognosia would include any denial of impairment, such as denial of blindness (Anton’s syndrome). But Babinski, who introduced the term in 1914, applied it only to patients with hemiplegia who fail to acknowledge their paralysis. Most commonly, this is failure to acknowledge paralysis of the left side of the body following damage to the right hemisphere of the brain. In this paper, we shall mainly be concerned with anosognosia for hemiplegia. But we shall also use the term ‘anosognosia’ in an inclusive way to encompass lack of knowledge or acknowledgement of any impairment. Indeed, in the construction ‘anosognosia for X’, X might even be anosognosia for some Y

Abstract: The sense of embodiment is vital for self recognition. An examination of anosognosia for hemiplegia—the inability to recognise that one is paralysed down one side of one’s body—suggests the existence of ‘online’ and ‘offline’ representations of the body. Online representations of the body are representations of the body as it is currently, are newly constructed moment by moment and are directly “plugged into” current perception of the body. In contrast, offline representations of the body are representations of what the body is usually like, are relatively stable and are constructed from online representations. This distinction is supported by an analysis of phantom limb—the feeling that an amputated limb is still present—phenomena. Initially it seems that the sense of embodiment may arise from either of these types of representation; however, an integrated representation of the body seems to be required. It is suggested information from vision and emotions is involved in generating these representations. A lack of access to online representations of the body does not necessarily lead to a loss in the sense of embodiment. An integrated offline representation of the body could account for the sense of embodiment and perform the functions attributed to this sense.

Abstract: Neurostimulation to restore cognitive and physical functions is an innovative and promising technique for treating patients with severe brain injury that has resulted in a minimally conscious state (MCS). The technique may involve electrical stimulation of the central thalamus, which has extensive projections to the cerebral cortex. Yet it is unclear whether an improvement in neurological functions would result in a net benefit for these patients. Quality-of-life measurements would be necessary to determine whether any benefit of neurostimulation outweighed any harm in their response to different degrees of cognitive and physical disability. These measures could also indicate whether the technique could be ethically justified and whether surrogates could give proxy consent to its use on brain-injured patients

Abstract: Recent progress in neurosciences has improved our understanding of chronic disorders of consciousness. One example of this advancement is the emergence of the new diagnostic category of minimally conscious state (MCS). The central characteristic of MCS is impaired consciousness. Though the phenomenon now referred to as MCS pre-existed its inclusion in diagnostic classifications, the current medical ethical concepts mainly apply to patients with normal consciousness and to non-conscious patients. Accordingly, how we morally should stand with persons in minimally conscious state remains unclear. In this paper, I examine whether the notion of human dignity could provide us with guidance with the moral difficulties MCS gives rise to. More precisely, I focus on the question of whether we are justified in holding that persons in minimally conscious state possess human dignity

Abstract: In this article, I consider whether the advance directive of a person in minimally conscious state ought to be adhered to when its prescriptions conflict with her current wishes. I argue that an advance directive can have moral significance after its issuer has succumbed to minimally conscious state. I also defend the view that the patient can still have a significant degree of autonomy. Consequently, I conclude that her advance directive ought not to be applied. Then I briefly assess whether considerations pertaining to respecting the patient's autonomy could still require obedience to the desire expressed in her advance directive and arrive at a negative answer

Abstract: The article briefly analyzes the concept of a person, arguing that personhood does not coincide with the actual enjoyment of certain intellectual capacities, but is coextensive with the embodiment of a human individual. Since in PVS patients we can observe a human individual functioning as a whole, we must conclude that these patients are still human persons, even if in a condition of extreme impairment. It is then argued that some forms of minimal treatment may not be futile for these patients; they may constitute a form of respect for their human dignity and benefit these patients, even if they are not aware of that. Moreover, it is important to consider the symbolic significance of care: while many believe that PVS is a kind of imprisonment, for others providing food and fluids is the only way to testify our proximity to these persons. The best policy would be to provide, as a general rule, artificial nutrition and hydration to PVS patients: this treatment could be withdrawn, after a period of observation and reflection by the family and proxies, on the basis of the proxies' objection to the continuation or of the patient's advance directives specifically referring to this situation

Abstract: Coma, vegetative state, lock-in syndrome and akinetic mutism are defined. Vegetative state is a state with no evidence of awareness of self or environment and showing cycles of sleep and wakefulness. PVS is an operational definition including time as a variable. PVS is a vegetative state that has endured or continued for at least one month. PVS can be diagnosed with a reasonable amount of medical certainty; however, the diagnosis of PVS must be kept separate from the outcome. The patient outcome can be predicted based on etiology and age. Using outcome probabilities and etiology as criteria, patients can be subdivided in 5 groups and reasonable management guidelines can be suggested. Three levels of care can be provided to PVS patients: high technology, supportive and compassionate care. Pragmatic options for the various subgroups of patients are suggested. Management decisions will remain difficult for both the family and the health-care team. The role of the physician in these difficult cases is to share the decision-making with the family

Abstract: A survey of the medical, ethical and legal issues that surround this controversial topic.

Abstract: Neuroimaging studies of brain-damaged patients diagnosed as in the vegetative state suggest that the patients might be conscious. This might seem to raise no new ethical questions given that in related disputes both sides agree that evidence for consciousness gives strong reason to preserve life. We question this assumption. We clarify the widely held but obscure principle that consciousness is morally significant. It is hard to apply this principle to difficult cases given that philosophers of mind distinguish between a range of notions of consciousness and that is unclear which of these is assumed by the principle. We suggest that the morally relevant notion is that of phenomenal consciousness and then use our analysis to interpret cases of brain damage. We argue that enjoyment of consciousness might actually give stronger moral reasons not to preserve a patient's life and, indeed, that these might be stronger when patients retain significant cognitive function.

Abstract: : This article begins with a discussion of persistent vegetative state (PVS), focusing on concerns related to both diagnosis and prognosis and paying special attention to the 1994 Multi-Society Task Force report on the medical aspects of PVS. The article explores the impact of diagnostic and prognostic uncertainties on prospective thinking regarding the possibility of PVS and considers the closely related question of how prospective thinkers might craft advance directives in order to deal most effectively with this possibility

Abstract: While Agamben acknowledges the Arendtian and Foucaultian thesis of the modernity of biopower, he will claim that sovereignty and biopolitics are equally ancient and essentially intertwined in the originary gesture of all politics; sovereignty is the power to decide the state of exception whereby bare life or zoe is exposed "underneath" political life or bios. Agamben then finds in the concentration camp the modern biopolitical paradigm, in which the state of exception has become the rule and we have all become [potentially] bearers of exposed bare life in that we are all subject to what I will call a "de-politicizing predication": to use the current American jargon, being named an "enemy combatant."

Abstract: In the first part of this talk I show how some ideas in the new "4EA" branch of cognitive science (embodied, embedded, extended, enactive, affective), which gets away from the computer metaphor to talk about affective cognition as the direction of action of an organism, can be illuminated by Deleuze's ontology. Now that may sound ridiculous, as Deleuze's terminology is notoriously baroque – how could it ever "illuminate" anything? So I'm going to be using plain English translations of his concepts; I think his concepts are too good, too useful, for his terminology to be such a barrier to entry. Then I'm going to use this mixture of Deleuze and 4EA ideas to examine a case study which has, besides its metaphysical and psychological implications, some ethical, political, and legal ones as well. So to deal with them we'll deal just a bit with Agamben and Foucault

Abstract: In this article I contend that the tendency to equate coma with anencephalia is a mistake. A key idea here is that there is a type of "mental-state" predicate that is applicable to the comatose but not to anencephalics. One of the moral implications of this is that the concept of "brain death", its alleged popularity notwithstanding, is badly confused. Also, because anencephalics have no mental life, there are few moral grounds for hesitating to use anencephalics as organ donors

Abstract: Disorders of consciousness and the permanent vegetative state -- Legal and political wrangling over Terri's life -- In context--law and ethics -- Terri's wishes -- The limits of evidence -- The implications of surrogacy -- Qualities of life -- Feeding -- The preservation of life -- Respect and care : an alternative framework.

Abstract: Consciousness in experimental subjects is typically inferred from reports and other forms of voluntary behaviour. A wealth of everyday experience confirms that healthy subjects do not ordinarily behave in these ways unless they are conscious. Investigation of consciousness in vegetative state (VS) patients has been based on the search for neural evidence that such broad functional capacities are preserved in some VS patients. We call this the standard approach. To date, the results of the standard approach have suggested that some VS patients might indeed be conscious, although they fall short of being demonstrative. The fact that some VS patients show evidence of consciousness according to the standard approach is remarkable, for the standard approach to consciousness is rather conservative, and leaves open the pressing question of how to ascertain whether patients who fail such tests are conscious or not. We argue for a cluster-based ‘natural kind’ methodology that is adequate to that task, both as a replacement for the approach that currently informs research into the presence or absence of consciousness in VS patients, and as a methodology for the science of consciousness more generally

Abstract: Current research on the neural basis of consciousness is based mainly on neuroimaging, physiology and psychophysics. This target article reviews what is known about biochemical factors that may contribute to the development of consciousness, based on loss of consciousness (i.e., coma). There are two theories of the biochemical mode of action of general anaesthetics. One is that anaesthesia is a direct (i.e., not receptor-mediated) effect of the anaesthetic on cellular neurophysiological function; the other is that some alteration of receptor function occurs. General anaesthetics are mainly GABA agonists but some (such as ketamine) are glutamate antagonists. They also affect other systems, particularly cholinergic ones. There are various comas of metabolic origin. For example, a combination of small doses of the iron chelators desferrioxamine and prochlorperazine induce a profound and long lasting coma in humans. The mechanisms that might mediate this include redox mechanisms at the glutamate synapse, post-synaptic endocytosis of dopamine and iron, and intracellular iron-dopamine complexes, which are powerful dismuters of the superoxide anion. New findings in cell biology relating to endocytosis and recycling of receptors are discussed in a wider context. These biochemical events may induce coma by two mechanisms: (i) Consciousness may depend on widespread cortical (or cortico-thalamic) activation. (ii) Whereas these biochemical changes are widespread, only the changes in a subset of consciousness' neurons may count. An experimental program to distinguish between these two alternatives is proposed

Abstract: Brain damage can cause massive changes in consciousness levels. From a clinical and ethical point of view it is desirable to assess the level of residual consciousness in unresponsive patients. However, no direct measure of consciousness exists, so we run into the philosophical problem of other minds. Neurologists often make implicit use of a Turing test-like procedure in an attempt to gain access to damaged minds, by monitoring and interpreting neurobehavioral responses. New brain imaging techniques are now being developed that permit communication with unresponsive patients, using their brain signals as carriers of messages relating to their mental states

Abstract: To aid neuroscientists in determining the ethical limits of their work and its applications, neuroethical problems need to be identified, catalogued, and analyzed from the standpoint of an ethical framework. Many hospitals have already established either autonomy or welfare-centered theories as their adopted ethical framework. Unfortunately, the choice of an ethical framework resists resolution: each of these two moral theories claims priority at the exclusion of the other, but for patients with neurological pathologies, concerns about the patient’s welfare are treated as meaningless without consideration of the patient’s expressed wishes, and vice versa. Ethicists have long fought over whether suffering or autonomy should be our primary concern, but in neuroethics a resolution of this question is essential to determine the treatment of patients in medical and legal limbo. I propose a solution to this problem in the form of ethical dualism. My paper deviates from this text in many ways, but especially in the inclusion of autonomy and happiness as part of ethical theories, rather than guiding principles. This is a conservative measure in that it retains both sides of the debate: both happiness and autonomy have intrinsic value. However, this move is often met with resistance because of its more complex nature—it is more difficult to make a decision when there are two parallel sets of values that must be considered than when there is just one such set. The monist theories, though, do not provide enough explanatory power: namely, I will present two recently publicized cases where it is clear that neither ethical value on its own (neither welfare nor autonomy) can fully account for how a vegetative patient should be treated. From the neuroethical cases of Terri Schiavo and Lauren Richardson, I will argue that a dualist framework is superior to its monist predecessors, and I will describe the main features of such an account

Abstract: All-encompassing text examines every aspect of coma from neurochemistry, monitoring, and treatments to prognostic factors.

Abstract: Does synesthesia undermine representationalism? Gregg Rosenberg (2004) argues that it does. On his view, synesthesia illustrates how phenomenal properties can vary independently of representational properties. So, for example, he argues that sound/color synesthetic experiences show that visual experiences do not always represent spatial properties. I will argue that the representationalist can plausibly answer Rosenberg

Abstract: Extreme conditions like savantism, autism or synaesthesia, which have a neurological 2AH, UK basis, challenge the idea that other minds are similar to our own. In this paper we report a single case study of a man in whom all three of these conditions co-occur. We suggest, on the basis of this single case, that when savantism and synaesthesia co- occur, it is worthwhile testing for an undiagnosed Autism Spectrum Condition (ASC). This is because savantism has an established association with ASC, and the combination of ASC with synaesthesia may increase the likelihood of savantism. The implications of these conditions for philosophy of mind are introduced

Abstract: Fodor claims that cognitive modules can be thought of as constituting a psychological natural kind in virtue of their possession of most or all of nine specified properties. The challenge to this considered here comes from synaesthesia. Synaesthesia is a type of cross-modal association: input to one sensory modality reliably generates an additional sensory output that is usually generated by the input to a distinct sensory modality. The most common form of synaesthesia manifests Fodor's nine specified properties of modularity, and hence, according to Segal (1997), it should be understood as involving an extra module. Many psychologists believe that synaesthesia involves a breakdown in modularity. After outlining how both theories can explain the manifestation of the nine alleged properties of modularity in synaesthesia, I discuss the two concepts of function which initially motivate the respective theories. I argue that only a teleological concept of function is properly able to adjudicate between the two theories. The upshot is a further application of so-called externalist considerations to mental phenomena

Abstract: Wager has argued that synaesthesia provides material for a counterexample to representational theories of the phenomenal character of experience. He gives a series of three cases based on synaesthesia; he requires the second and third cases to bolster the doubtfulness of the first. Here I further endorse the problematic nature of the first case and then show why the other two cases do not save his argument. I claim that whenever synaesthesia is a credible possibility its phenomenal character can be understood in terms of misrepresentation

Abstract: The aim of this article is to give both a sustained interpretation of Wittgenstein’s obscure remarks on the experience of meaning of language, synthaesthesia and secondary use and to apply his insights to recent philosophical discussions about synthaesthesia. I argue that synthaesthesia and experience of meaning are conceptually related to aspect-seeing. The concept of aspect-seeing is not reducible to either seeing or imaging but involves a modified notion of experience. Likewise, synthaesthesia involves a modified notion of experience. In particular, the concept of synthaesthesia involves a secondary use of ‘experience’ and hence is intrinsically dependent on the primary use of language. Recent discussions tend to overlook this distinction between the primary and secondary use of language

Abstract: Synaesthesia is a condition in which one type of stimulation evokes the sensation of another, as when the hearing of a sound produces photisms, i.e. mental percepts of colours. R is a 20 year old colour blind subject who, in addition to the relatively common grapheme-colour synaesthesia, presents a rarely reported cross modal perception in which a variety of visual stimuli elicit aura-like percepts of colour. In R, photisms seem to be closely related to the affective valence of stimuli and typically bring out a consistent pattern of emotional responses. The present case study suggests that colours might be an intrinsic category of the human brain. We developed an empirical methodology that allowed us to study the subject's otherwise inaccessible phenomenological experience. First, we found that R shows a Stroop effect (delayed response due to interference) elicited by photisms despite the fact that he does not show a regular Stroop with real colours. Secondly, by manipulating the colour context we confirmed that colours can alter R's emotional evaluation of the stimuli. Furthermore, we demonstrated that R's auras may actually lead to a partially inverted emotional spectrum where certain stimuli bring out emotional reactions opposite to the normal ones. These findings can only be accounted for by considering R's subjective colour experience or qualia. Therefore the present paper defends the view that qualia are a useful scientific concept that can be approached and studied by experimental methods

Abstract: Jones and Coleman are among a handful of otherwise normal as a child and the number 5 was red and 6 was green. This the- people who have synesthesia. They experience the ordinary ory does not answer why only some people retain such vivid world in extraordinary ways and seem to inhabit a mysterious sensory memories, however. You might _think _of cold when you no-man’s-land between fantasy and reality. For them the sens- look at a picture of an ice cube, but you probably do not feel es—touch, taste, hearing, vision and smell—get mixed up in- cold, no matter how many encounters you may have had with stead of remaining separate. ice and snow during your youth. Modern scientists have known about synesthesia since Another prevalent idea is that synesthetes are merely being 1880, when Francis Galton, a cousin of Charles Darwin, pub- metaphorical when they describe the note C flat as “red” or say lished a paper in _Nature _on the phenomenon. But most have that chicken tastes “pointy”—just as you and I might speak of brushed it aside as fakery, an artifact of drug use (LSD and a “loud” shirt or “sharp” cheddar cheese. Our ordinary lan- mescaline can produce similar effects) or a mere curiosity. guage is replete with such sense-related metaphors, and perhaps About four years ago, however, we and others began to un- synesthetes are just especially gifted in this regard. cover brain processes that could account for synesthesia. Along We began trying to find out whether synesthesia is a gen- the way, we also found new clues to some of the most mysteri- uine sensory experience in 1999. This deceptively simple ques- ous aspects of the human mind, such as the emergence of ab- tion had plagued researchers in this field for decades. One nat- stract thought, metaphor and perhaps even language. ural approach is to start by asking the subjects outright: “Is this A common explanation of synesthesia is that the affected just a memory, or do you actually see the color as if it were right people are simply experiencing childhood memories and asso- in front of you?” When we tried asking this question, we did ciations..

Abstract: We studied two otherwise normal, synaesthetic subjects who `saw' a speci¢c colour every time they saw a speci¢c number or letter. We conducted four experiments in order to show that this was a genuine perceptual experience rather than merely a memory association. (i)The synaesthetically induced colours could lead to perceptual grouping, even though the inducing numerals or letters did not. (ii)Synaesthetically induced colours were not experienced if the graphemes were presented peripherally. (iii)Roman numerals were ine¡ective: the actual number grapheme was required. (iv)If two graphemes were alternated the induced colours were also seen in alternation. However, colours were no longer experienced if the graphemes were alternated at more than 4 Hz. We propose that grapheme colour synaesthesia arises from `cross-wiring' between the `colour centre' (area V4 or V8)and the `number area', both of which lie in the fusiform gyrus. We also suggest a similar explanation for the representation of metaphors in the brain: hence, the higher incidence of synaesthesia among artists and poets

Abstract: (1) The induced colours led to perceptual grouping and pop-out, (2) a grapheme rendered invisible through ‘crowding’ or lateral masking induced synaesthetic colours — a form of blindsight — and (3) peripherally presented graphemes did not induce colours even when they were clearly visible. Taken collectively, these and other experiments prove conclusively that synaesthesia is a genuine percep- tual phenomenon, not an effect based on memory associations from childhood or on vague metaphorical speech. We identify different subtypes of number–colour synaesthesia and propose that they are caused by hyperconnectivity between col- our and number areas at different stages in processing; lower synaesthetes may have cross-wiring (or cross-activation) within the fusiform gyrus, whereas higher synaesthetes may have cross-activation in the angular gyrus. This hyperconnec- tivity might be caused by a genetic mutation that causes defective pruning of con- nections between brain maps. The mutation may further be expressed selectively (due to transcription factors) in the fusiform or angular gyri, and this may explain the existence of different forms of synaesthesia. If expressed very diffusely, there may be extensive cross-wiring between brain regions that represent abstract concepts, which would explain the link between creativity, metaphor and synaesthesia (and the higher incidence of synaesthesia among artists and poets). Also, hyperconnectivity between the sensory cortex and amygdala would explain the heightened aversion synaesthetes experience when seeing numbers printed in the ‘wrong’ colour. Lastly, kindling (induced hyperconnectivity in the temporal lobes of temporal lobe epilepsy [TLE] patients) may explain the purported higher incidence of synaesthesia in these patients. We conclude with a synaesthesia-based theory

Abstract: This article supplements our earlier paper on synaesthesia published in JCS (Ramachandran & Hubbard, 2001a). We discuss the phenomenology of synaesthesia in greater detail, raise several new questions that have emerged from recent studies, and suggest some tentative answers to these questions

Abstract: Synesthesia is a condition in which stimulation in one modality also gives rise to a perceptual experience in a second modality. In two recent studies we found that the condition is more common than previously reported; up to 5% of the population may experience at least one type of synesthesia. Although the condition has been traditionally viewed as an anomaly (e.g., breakdown in modularity), it seems that at least some of the mechanisms underlying synesthesia do reflect universal cross-modal mechanisms. We review here a number of examples of cross-modal correspondences found in both synesthetes and non-synesthetes including pitch-lightness and vision-touch interaction, as well as cross-domain spatial- numeric interactions. Additionally, we discuss the common role of spatial attention in binding shape and color surface features (whether ordinary or synesthetic color). Consistently with behavioral and neuroimaging data showing that chromatic-graphemic (colored-letter) synesthesia is a genuine perceptual phenomenon implicating extrastriate cortex, we also present electrophysiological data showing modulation of visual evoked potentials by synesthetic color congruency

Abstract: Gray argues that my three earlier counterexamples fail to refute representational theories of phenomenal character. I maintain that, despite Gray's arguments, each example does in fact work against the particular representational theory at which it is targeted. Further, I question whether my internalism regarding phenomenal character and Gray's externalism regarding modularity are in genuine conflict with one another

Abstract: Representationism is the view that the phenomenal character of an experience supervenes on its representational content. Synaesthesia is a condition in which the phenomenal character of the experience produced in a subject by stimulation of one sensory modality contains elements characteristic of a second, unstimulated sensory modality. After reviewing some of the recent psychological literature on synaesthesia and one of the leading versions of representationism, I argue that cases of synaesthesia, as instances of what I call the extra qualia problem, are counterexamples to externalist versions of representationism

Abstract: Synaesthesia is considered a rare perceptual capacity, and one that is not capable of cultivation. However, meditators report the experience quite commonly, and in questionnaire surveys, respondents claimed to experience synaesthesia in 35% of meditation retreatants, in 63% of a group of regular meditators, and in 86% of advanced teachers. These rates were significantly higher than in nonmeditator controls, and displayed significant correlations with measures of amount of meditation experience. A review of ancient texts found reports suggestive of synaesthesia in advanced meditators from India and China. These findings suggest that synaesthesia may be cultivated by meditation, and that laboratory studies of meditators could be rewarding

Abstract: Studies of perception have focussed on sensation, though more recently the perception of action has, once more, become the subject of investigation. These studies have looked at acute experimental situations. The present paper discusses the subjective experience of those with either clinical syndromes of loss of movement or sensation (spinal cord injury, sensory neuronopathy syndrome or motor stroke), or with experimental paralysis or sensory loss. The differing phenomenology of these is explored and their effects on intention and agency discussed. It is shown that sensory loss can have effects on the focussing of motor command and that for some a sense of agency can return despite paralysis

Abstract: David Milner and Melvyn Goodale, and the many psychologists and philosophers who have been influenced by their work, claim that ‘the visual system that gives us our visual experience of the world is not the same system that guides our movements in the world’. The arguments that have been offered for this surprising claim place considerable weight on two sources of evidence — visual form agnosia and the reaching behaviour of normal subjects when picking up objects that induce visual illusions. The present article shows that, if we are careful to consider the possibility that a demonstrative gesture can contribute content to a conscious experience, then neither source of evidence is compelling.

Abstract:   The neural substrate of early visual processing in the macaque is used as a framework to discuss recent progress towards a precise anatomical localization and understanding of the functional implications of the syndromes of blindsight, achromatopsia and akinetopsia in humans. This review is mainly concerned with how these syndromes support the principles of organization of the visual system into parallel pathways and the functional hierarchy of visual mechanisms