Should people include beef in their diet? This chapter argues that the answer is “no” by reviewing what is known and not known about the presence in cattle of three psychological traits: pain, desire, and self-consciousness. On the basis of behavioral and neuroanatomical evidence, the chapter argues that cattle are sentient beings who have things they want to do in the proximal future, but they are not self-conscious. The piece rebuts three important objections: that cattle have injury information (...) but not pain; that cattle have goal-directed behavior but not desire; and that the absence of evidence for bovine self-consciousness should not be taken as evidence that cattle lack self-consciousness. In sum, what is known about cattle cognition shifts the moral burden of proof on to the beef eaters. (shrink)

Can scientific evidence prompt us to revise philosophical theories or folk theoretical accounts of phenomena of the mind? We will argue that it can—but only under the condition that they make a so-called ‘ontological commitment’ to something that is actually subject to empirical inquiry. In other words, scientific evidence pertaining to neuroanatomical structure or causal processes only has a refuting effect if philosophical theories and folk notions subscribe to either account. We will illustrate the importance of ‘ontological (...) commitment’ with the ‘neuroanatomical approach’ to amusement as proposed in a recent paper by Palencik :419–434, 2007). We will show that the scientific evidence presented in said neuroanatomical approach has no bearing on the conceptual issues, in that the philosophical theories and folk distinction that are criticized do not subscribe to any account of the underlying neuroanatomical structure or causal processes. Our suggestions in this paper are not limited to philosophical accounts of humor but apply to the relationship of philosophy, common sense and science in general. (shrink)

A unifying theory of general anesthetic-induced unconsciousness must explain the common mechanism through which various anesthetic agents produce unconsciousness. Functional-brain-imaging data obtained from 11 volunteers during general anesthesia showed specific suppression of regional thalamic and midbrain reticular formation activity across two different commonly used volatile agents. These findings are discussed in relation to findings from sleep neurophysiology and the implications of this work for consciousness research. It is hypothesized that the essential common neurophysiologic mechanism underlying anesthetic-induced unconsciousness is, as with (...) sleep-induced unconsciousness, a hyperpolarization block of thalamocortical neurons. A model of anesthetic-induced unconsciousness is introduced to explain how the plethora of effects anesthetics have on cellular functioning ultimately all converge on a single neuroanatomic/neurophysiologic system, thus providing for a unitary physiologic theory of narcosis related to consciousness. (shrink)

Nurses in Ghana believe that training, practise, practitioner and policy reforms are required for total nursing profession reform to be effective. Their views for role reformation in the nursing profession, which is currently needed, are not only academic but also clinically relevant in the pursuit of health equity and quality nursing care. We explored and described nurses’ views on their roles in the profession using data collected from 24 professional nurses in three regional hospitals in Ghana. Using an inductive descriptive (...) qualitative design, data were gathered and analysed using a qualitative content analysis to describe the views of the nurses. Four major themes, namely practise reforms, practitioner reforms, training reforms and policy reforms have emerged in relation to role reformation in the nursing profession. Three strategic areas, practitioner attitudes, new training modalities and policy realignment, must be reviewed and remodelled for better positioning of the nursing profession before its entire role reformation. (shrink)

Inner speech has been shown to vary in form along several dimensions. Along condensation, condensed inner speech forms have been described, that are supposed to be deprived of acoustic, phonological and even syntactic qualities. Expanded forms, on the other extreme, display articulatory and auditory properties. Along dialogality, inner speech can be monologal, when we engage in internal soliloquy, or dialogal, when we recall past conversations or imagine future dialogues involving our own voice as well as that of others addressing us. (...) Along intentionality, it can be intentional (when we deliberately rehearse material in short-term memory) or it can arise unintentionally (during mind wandering). We introduce the ConDialInt model, a neurocognitive predictive control model of inner speech that accounts for its varieties along these three dimensions. ConDialInt spells out the condensation dimension by including inhibitory control at the conceptualization, formulation or articulatory planning stage. It accounts for dialogality, by assuming internal model adaptations and by speculating on neural processes underlying perspective switching. It explains the differences between intentional and spontaneous varieties in terms of monitoring. We present an fMRI study in which we probed varieties of inner speech along dialogality and intentionality, to examine the validity of the neuroanatomical correlates posited in ConDialInt. Condensation was also informally tackled. Our data support the hypothesis that expanded inner speech recruits speech production processes down to articulatory planning, resulting in a predicted signal, the inner voice, with auditory qualities. Along dialogality, covertly using an avatar’s voice resulted in the activation of right hemisphere homologues of the regions involved in internal own-voice soliloquy and in cerebellar deactivation, consistent with internal model adaptation. Switching from first-person to third-person perspective resulted in activations in precuneus and parietal lobules. Along intentionality, compared with intentional inner speech, mind wandering with inner speech episodes was associated with greater bilateral inferior frontal activation and decreased activation in left temporal regions. This is consistent with the reported subjective evanescence and presumably reflects condensation processes. Our results provide neuroanatomical evidence compatible with predictive control and in favor of the assumptions made in the ConDialInt model. (shrink)

Part of understanding the functional organization of the brain is understanding how it evolved. This talk presents evidence suggesting that while the brain may have originally emerged as an organ with functionally dedicated regions, the creative re-use of these regions has played a significant role in its evolutionary development. This would parallel the evolution of other capabilities wherein existing structures, evolved for other purposes, are re-used and built upon in the course of continuing evolutionary development (“exaptation”: Gould & Vrba (...) 1982). There is psychological support for exaptation in cognition (e.g. Cosmides 1989), theoretical reason to expect it (Anderson 2003; in press-a; in press-b) and neuroanatomic evidence that the brain evolved by preserving, extending, and combining existing network components, rather than by generating complex structures de novo (Sporns & Kötter 2004). However, there has been little evidence that integrates these perspectives, bringing such an account of the evolution of cognitive function into the realm of cognitive neuroscience (although see, e.g., Barsalou 1999). (shrink)

Cognitive and emotional processes are now known to be intertwined and thus the limbic system that underlies emotions is important for human brain evolution, including the evolution of circuits supporting language. The neural substrates of limbic functions, like motivation, attention, inhibition, evaluation, detection of emotional stimuli and others have changed over time. Even though no new, added structures are present in the human brain compared to nonhuman primates, evolution tweaks existing structural systems with possible functional implications. Empirical comparative neuroanatomical (...) evidence is presented here in support of such changes in the limbic system, including the amygdala and the orbitofrontal cortex. Given their possible functional significance, these alterations may further enable and enhance human interest and motivation to communicate beyond what is seen in other primates living in complex social groups. The argument here is that even though emotion processing is likely needed for increased social complexity independent of language, the reason why humans want to talk may be related in part to the enhancement of socioemotional processes resulting from the reorganization and rewiring of underlying neural systems some of which are interconnected to the language areas. Neurodevelopmental disorders in humans affecting both language and sociability fuel such arguments. (shrink)

The anterior cingulate cortex (ACC)has been identified as part of a supervisoryattentional network for selecting alternativemotor programs in response to top-down corticalprocessing, particularly in situationsinvolving conflicting cognitive tasks.Bilateral lesions to the ACC may be causallyassociated with akinetic mutism, where patientsare unable to voluntarily initiate responses.The clinical and neuroanatomical evidence forthis presumed causal association is examined atlength. However, given the many reciprocalprojections between cerebral, motor, limbic andparalimbic structures within the executivesupervisory network, the association ofvoluntary behavior with a particular structure(the (...) ACC) is highly controversial and thereforepremature at this time. Also considered is theclaim that our subjective sense of voluntarycontrol and free will is simply due toour not having conscious access to theunderlying neural computations that precede our decisions and actions. On thecontrary, the distinction between voluntary and involuntary thoughts and actions mayrather be a matter of temporal and directionallag between parallel computations in differentneural areas. Finally, with reference toDennett, there is an extended discussion ofwhether patients with akinetic mutism are (i) conscious automata, (ii) non-intentional systems, and (iii) in azombie-like state. The relevance of (i)–(iii) for the cognitive neuroscientificliterature is then briefly addressed. (shrink)

The neuroanatomical substrates controlling and regulating sleeping and waking, and thus consciousness, are located in the brain stem. Most crucial for bringing the brain into a state conducive for consciousness and information processing is the mesencephalic part of the brain stem. This part controls the state of waking, which is generally associated with a high degree of consciousness. Wakefulness is accompanied by a low-amplitude, high-frequency electroencephalogram, due to the fact that thalamocortical neurons fire in a state of tonic depolarization. (...) Information can easily pass the low-level threshold of these neurons, leading to a high transfer ratio. The complexity of the electroencephalogram during conscious waking is high, as expressed in a high correlation dimension. Accordingly, the level of information processing is high. Spindles, and alpha waves in humans, mark the transition from wakefulness to sleep. These phenomena are related to drowsiness, associated with a reduction in consciousness. Drowsiness occurs when cells undergo moderate hyperpolarizations. Increased inhibitions result in a reduction of afferent information, with a lowered transfer ratio. Information processing subsides, which is also expressed in a diminished correlation dimension. Consciousness is further decreased at the onset of slow wave sleep. This sleep is controlled by the medullar reticular formation and is characterized by a high-voltage, low-frequency electroencephalogram. Slow wave sleep becomes manifest when neurons undergo a further hyperpolarization. Inhibitory activities are so strong that the transfer ratio further drops, as does the correlation dimension. Thus, sensory information is largely blocked and information processing is on a low level. Finally, rapid eye movement sleep is regulated by the pontine reticular formation and is associated with a ''wake-like'' electroencephalographic pattern. Just as during wakefulness, this is the expression of a depolarization of thalamocortical neurons. The transfer ratio of rapid eye movement sleep has not yet been determined, but seems to vary. Evidence exists that this type of sleep, associated with dreaming, with some kind of perception and consciousness, is involved in processing of ''internal'' information. In line with this, rapid eye movement sleep has higher correlation dimensions than slow-wave sleep and sometimes even higher than wakefulness. It is assumed that the ''near-the-threshold'' depolarized state of neurons in the thalamus and cerebral cortex is a necessary condition for perceptual processes and consciousness, such as occurs during waking and in an altered form during rapid eye movement sleep. (shrink)

Measuring event-related potentials (ERPs) has been fundamental to our understanding of how language is encoded in the brain. One particular ERP response, the N400 response, has been especially influential as an index of lexical and semantic processing. However, there remains a lack of consensus on the interpretation of this component. Resolving this issue has important consequences for neural models of language comprehension. Here we show that evidence bearing on where the N400 response is generated provides key insights into what (...) it reflects. A neuroanatomical model of semantic processing is used as a guide to interpret the pattern of activated regions in functional MRI, magnetoencephalography and intracranial recordings that are associated with contextual semantic manipulations that lead to N400 effects. (shrink)

Semantic perceptualism is the thesis that meaning experiences are forms of perceptual experiences. According to its defenders, this view is motivated not only by philosophical considerations, but also by empirical evidence. In the present article, I shall provide the first comprehensive and critical review of the empirical evidence in support of semantic perceptualism, including a detailed analysis of the relevant neuroanatomical data. The conclusions of my analysis are largely pessimistic. I believe that the relevant behavioral, cognitive, and (...) patient data are suggestive but hardly conclusive. Moreover, neuroanatomical data speak strongly against semantic perceptualism. (shrink)

In this paper we consider two major issues: conceptual–experimental approaches to the self, and the neuroanatomical substrate of the self. We distinguish content- and processed-based concepts of the self that entail different experimental strategies, and anatomically, we investigate the concept of midline structures in further detail and present a novel view on the anatomy of an integrated subcortical–cortical midline system. Presenting meta-analytic evidence, we show that the anterior paralimbic, e.g. midline, regions do indeed seem to be specific for (...) self-specific stimuli. We conclude that future investigation of the self need to develop novel concepts that are more empirically plausible than those currently in use. Different concepts of self will require novel experimental designs that include, for example, the brain’s resting state activity as an independent variable. Modifications of both conceptual and anatomical dimensions will allow an empirically more plausible account of the relationship between brain and self. (shrink)

In recent years, the scientific study of meditation and psychedelic drugs has seen remarkable developments. The increased focus on meditation in cognitive neuroscience has led to a cross-cultural classification of standard meditation styles validated by functional and structural neuroanatomical data. Meanwhile, the renaissance of psychedelic research has shed light on the neurophysiology of altered states of consciousness induced by classical psychedelics, such as psilocybin and LSD, whose effects are mainly mediated by agonism of serotonin receptors. Few attempts have been (...) made at bridging these two domains of inquiry, despite intriguing evidence of overlap between the phenomenology and neurophysiology of meditation practice and psychedelic states. In particular, many contemplative traditions explicitly aim at dissolving the sense of self by eliciting altered states of consciousness through meditation, while classical psychedelics are known to produce significant disruptions of self-consciousness, a phenomenon known as drug-induced ego dissolution. In this article, we discuss available evidence regarding convergences and differences between phenomenological and neurophysiological data on meditation practice and psychedelic drug-induced states, with a particular emphasis on alterations of self-experience. While both meditation and psychedelics may disrupt self-consciousness and underlying neural processes, we emphasize that neither meditation nor psychedelic states can be conceived as simple, uniform categories. Moreover, we suggest that there are important phenomenological differences even between conscious states described as experiences of self-loss. As a result, we propose that self-consciousness may be best construed as a multidimensional construct, and that “self-loss,” far from being an unequivocal phenomenon, can take several forms. Indeed, various aspects of self-consciousness, including narrative aspects linked to autobiographical memory, self-related thoughts and mental time travel, and embodied aspects rooted in multisensory processes, may be differently affected by psychedelics and meditation practices. Finally, we consider long-term outcomes of experiences of self-loss induced by meditation and psychedelics on individual traits and prosocial behavior. We call for caution regarding the problematic conflation of temporary states of self-loss with “selflessness” as a behavioral or social trait, although there is preliminary evidence that correlations between short-term experiences of self-loss and long-term trait alterations may exist. (shrink)

Moral and legal notions engaged in clinical ethics should not only possess analytic clarity but a sound basis in empirical findings. The latter condition brings into question the expansion of the mature minor exception. The mature minor exception in the healthcare law of the United States has served to enable those under the legal age to consent to medical treatment. Although originally developed primarily for minors in emergency or quasi-emergency need for health care, it was expanded especially from the 1970s (...) in order to cover unemancipated minors older than 14 years. This expansion initially appeared plausible, given psychological data that showed the intellectual capacity of minors over 14 to recognize the causal connection between their choices and the consequences of their choices. However, subsequent psychological studies have shown that minors generally fail to have realistic affective and evaluative appreciations of the consequences of their decisions, because they tend to over-emphasize short-term benefits and underestimate long-term risks. Also, unlike most decisionmakers over 21, the decisions of minors are more often marked by the lack of adequate impulse control, all of which is reflected in the far higher involvement of adolescents in acts of violence, intentional injury, and serious automobile accidents. These effects are more evident in circumstances that elicit elevated affective responses. The advent of brain imaging has allowed the actual visualization of qualitative differences between how minors versus persons over the age of 21 generally assess risks and benefits and make decisions. In the case of most under the age of 21, subcortical systems fail adequately to be checked by the prefrontal systems that are involved in adult executive decisions. The neuroanatomical and psychological model developed by Casey, Jones, and Summerville offers an empirical insight into the qualitative differences in the neuroanatomical and neuropsychological bases of adolescent versus adult decision making. These and other data, as well as developing law bearing on the culpability of juvenile criminal offenders, argue for critically re-evaluating the expansion of the mature minor exception with regard to medical decision making, as well as in support of a rebuttable presumption in favor of treating minors as immature decisionmakers. The clinical ethics of adolescent medical decision making will need foundationally to be reconsidered. (shrink)

Several influential philosophers and scientists have advanced a framework, often called Neo-Cartesianism (NC), according to which animal suffering is merely apparent. Drawing upon contemporary neuroscience and philosophy of mind, Neo-Cartesians challenge the mainstream position we shall call Evolutionary Continuity (EC), the view that humans are on a nonhierarchical continuum with other species and are thus not likely to be unique in consciously experiencing negative pain affect. We argue that some Neo-Cartesians have misconstrued the underlying science or tendentiously appropriated controversial views (...) in the philosophy of mind. We discuss recent evidence that undermines the simple neuroanatomical structure-function correlation thesis that undergirds many Neo-Cartesian arguments, has an important bearing on the recent controversy over pain in fish, and places the underlying epistemology framing the debate between NC and EC in a new light that strengthens the EC position. (shrink)

This target article presents a plausible evolutionary scenario for the emergence of the neural preconditions for language in the hominid lineage. In pleistocene primate lineages there was a paired evolutionary expansion of frontal and parietal neocortex (through certain well-documented adaptive changes associated with manipulative behaviors) resulting, in ancestral hominids, in an incipient Broca's region and in a configurationally unique junction of the parietal, occipital, and temporal lobes of the brain (the POT). On our view, the development of the POT in (...) our ancestors resulted in the neuroanatomical substrate consistent with the ability for representations in modality-neutral association cortex and, as a result of structure-imposing interaction with Broca's area, the hierarchically structured Evidence from paleoneurology and comparative primate neuroanatomy is used to argue that Homo habilis (2.5–2 million years ago) was the first hominid to have the appropriate gross neuroanatomical configuration to support conceptual structure. We thus suggest that the neural preconditions for language are met in H. habilis. Finally, we advocate a theory of language acquisition that uses conceptual structure as input to the learning procedures, thus bridging the gap between it and language. (shrink)

For decades the study of social perception was largely compartmentalized by type of social cue: race, gender, emotion, eye gaze, body language, facial expression etc. This was partly due to good scientific practice, and partly due to assumptions that each type of social cue was functionally distinct from others. Herein, we present a functional forecast approach to understanding compound social cue processing that emphasizes the importance of shared social affordances across various cues. We review the traditional theories of emotion and (...) face processing that argued for dissociable and noninteracting pathways, as well as more recent evidence for combinatorial processing of social cues. We argue here that early, and presumably reflexive, visual integration of such cues is necessary for adaptive behavioral responding to others. In support of this claim, we review contemporary work that reveals a flexible visual system, one that readily incorporates meaningful contextual influences in even nonsocial visual processing, thereby establishing the functional and neuroanatomical bases necessary for compound social cue integration. Finally, we explicate three likely mechanisms driving such integration. Together, this work implicates a role for cognitive penetrability in visual perceptual abilities that have often been ascribed to direct encapsulated perceptual processes. (shrink)

This is the only book that examines the theory and data on the development of implicit and explicit memory. It first describes the characteristics of implicit and explicit memory (including conscious recollection) and tasks used with adults to measure them. Next, it reviews the brain mechanisms thought to underlie implicit and explicit memory and the studies with amnesics that initially prompted the search for different neuroanatomically-based memory systems. Two chapters review the Jacksonian (first in, last out) principle and empirical (...) class='Hi'>evidence for the hierarchical appearance and dissolution of two memory systems in animal models (rats, nonhuman primates), children, and normal/amnesic adults. Two chapters examine memory tasks used with human infants and evidence of implicit and explicit memory during early infancy. Three final chapters consider structural and processing accounts of adult memory dissociations, their applicability to infant memory dissociations, and implications of infant data for current concepts of implicit and explicit memory. (shrink)

We consider connections between number sense—the ability to judge number—and the interpretation of natural language quantifiers. In particular, we present empirical evidence concerning the neuroanatomical underpinnings of number sense and quantifier interpretation. We show, further, that impairment of number sense in patients can result in the impairment of the ability to interpret sentences containing quantifiers. This result demonstrates that number sense supports some aspects of the language faculty.

Profound sensorineural hearing loss is an auditory disability associated with auditory and cognitive dysfunction. Due to distinct pathogenesis, some associated structural and functional changes within the brain have been investigated in previous studies, but whole-brain structural alterations are incompletely understood. We extended the exploration of neuroanatomic differences in whole-brain structure in children with profound SNHL who are primarily users of Chinese sign language. We employed surface-based morphometry and subcortical analyses. T1-weighted magnetic resonance images of 26 children with profound SNHL and (...) 27 age- and sex-matched children with normal hearing were analyzed. Compared with the normal control group, children with profound SNHL showed diverse structural changes in surface-based and subcortical analyses, including decreased cortical thickness in the left postcentral gyrus, superior parietal lobule, paracentral lobule, precuneus, the right transverse temporal gyri, and the middle temporal gyrus; a noticeable increase in the Local Gyrification Index in the left precuneus and superior parietal lobule; and diverse changes in gray-matter volume in different brain regions. Surface-based vertex analyses revealed regional contractions in the right thalamus, putamen, pallidum, and the brainstem of children with profound SNHL when compared with those in the NC group. Volumetric analyses showed decreased volumes of the right thalamus and pallidum in children with profound SNHL. Our data suggest that children with profound SNHL are associated with diffuse cerebral dysfunction to cortical and subcortical nuclei, and revealed neuroplastic reorganization in the precuneus, superior parietal lobule, and temporal gyrus. Our study provides robust evidence for changes in connectivity and structure in the brain associated with hearing loss. (shrink)

When people talk, they gesture. Gesture is a fundamental component of language that contributes meaningful and unique information to a spoken message and reflects the speaker’s underlying knowledge and experiences. Theoretical perspectives of speech and gesture propose that they share a common conceptual origin and have a tightly integrated relationship, overlapping in time, meaning, and function to enrich the communicative context. We review a robust literature from the field of psychology documenting the benefits of gesture for communication for both speakers (...) and listeners, as well as its important cognitive functions for organizing spoken language, and facilitating problem-solving, learning, and memory. Despite this evidence, gesture has been relatively understudied in populations with neurogenic communication disorders. While few studies have examined the rehabilitative potential of gesture in these populations, others have ignored gesture entirely or even discouraged its use. We review the literature characterizing gesture production and its role in intervention for people with aphasia, as well as describe the much sparser literature on gesture in cognitive communication disorders including right hemisphere damage, traumatic brain injury, and Alzheimer’s disease. The neuroanatomical and behavioral profiles of these patient populations provide a unique opportunity to test theories of the relationship of speech and gesture and advance our understanding of their neural correlates. This review highlights several gaps in the field of communication disorders which may serve as a bridge for applying the psychological literature of gesture to the study of language disorders. Such future work would benefit from considering theoretical perspectives of gesture and using more rigorous and quantitative empirical methods in its approaches. We discuss implications for leveraging gesture to explore its untapped potential in understanding and rehabilitating neurogenic communication disorders. (shrink)

The success of deep brain stimulation (DBS) for movement disorders and the improved understanding of the neurobiologic and neuroanatomic bases of psychiatric diseases have led to proposals to expand current DBS applications. Recent preclinical and clinical work with Alzheimer's disease and obsessive-compulsive disorder, for example, supports the safety of stimulating regions in the hypothalamus and nucleus accumbens in humans. These regions are known to be involved in addiction and overeating associated with obesity. However, the use of DBS targeting these areas (...) as a treatment modality raises common ethical considerations, which include informed consent, coercion, enhancement, threat to personhood, and manipulation of the reward center. Pilot studies for both of these conditions are currently investigational. If these studies show promise, then there is a need to address the ethical concerns related to the initiation of clinical trials including the reliability of preclinical evidence, patient selection, study design, compensation for participation and injury, cost-effectiveness, and the need for long-term follow-up. Multidisciplinary teams are necessary for the ethical execution of such studies. In addition to establishing safety and efficacy, the consideration of these ethical issues is vital to the adoption of DBS as a treatment for these conditions. We offer suggestions about the pursuit of future clinical trials of DBS for the treatment of addiction and overeating associated with obesity and provide a framework for addressing ethical concerns related to treatment. (shrink)

Wilkins & Wakefield's identification of anatomical features in the Koobi Fora endocast, which may be thought to carry some functional significance in relation to organization for language, raises fundamental problems of method: attention is drawn to some limitations of the evidence, of endocasts and of the neuroanatomical map used to interpret them.

Specialized neural systems for encoding faces and face emotion cues are found in sheep which are very similar to those described in human and non-human primates. Sheep exhibit highly sophisticated face identity and face emotion discrimination skills, use configural cues, and also show right hemisphere dominance in face processing. Findings provide evidence for both sparse and population-based encoding with small populations of cells encoding selectively for specific individuals or categories of individual but nevertheless with widespread and overlapping neuronal activity (...) changes occurring across temporal cortex networks during the presentation of different faces. A number of studies have been carried out to map the neuroanatomical substrates involved in face recognition in sheep using quantification of expression changes in gene markers of neural activation. The face recognition system brings into sharp focus the ongoing debate as to whether sparse or population based codes or both are operating in the various cortical and subcortical networks involved. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Philosophy, Psychiatry, & Psychology 9.1 (2002) 61-63 [Access article in PDF] Arguing from Neuroscience in Psychiatry James Phillips PHILIP GERRANS "A One-stage Explanation of the Cotard Delusion" provides an elegant example of the application of neuroscientific findings to known clinical phenomena in psychiatry. Gerrans argues that, in the cases of the Cotard and Capgras delusions, a one-stage explanation is sufficient to account for the clinical phenomena. That is, the (...) neuroanatomic defect and the consequent anomalous experience are sufficient to produce the delusion. According to Gerrans, we do not need to postulate that the delusion will emerge only if the anomalous experience is filtered through a faulty reasoning process (a two-stage explanation). Against the argument of Young and Leafhead (1996) that Cotard and Capgras delusions stem from the same neuroanatomic deficit and differentiate only in being processed differently—thus requiring a two-stage explanation—Gerrans argues that the respective neuroanatomic defects are in fact different, and that, therefore, the two delusional syndromes differ at the first stage and do not require the two-stage explanation suggested by Young and Leafhead.I do not have an opinion as to who is right in this disagreement, and I will devote these remarks to explaining why I do not have an opinion. In developing this explanation I will touch on what I find problematic in many discussions of neuroscience, neurocognitive models, and clinical psychiatry; I will thus use this article to highlight those problems.On the face of it, one would think that the issue raised by Gerrans should admit of a simple resolution. He argues that Capgras and Cotard delusions derive from different neural defects. Young and Leafhead, on the other hand, base their two-stage argument on the argument that the two delusions derive from the same neural defect. So which is it? Neuroscientists should be able to settle the issue and end the dispute. Gerrans remarks "that we need to look more closely at the CN [cognitive neuropsychiatric] explanation of the Capgras delusion." As he describes it, face recognition involves two components, a cognitive and an affective component, with separate neuroanatomic substrates. An individual successfully recognizes the face of a friend or acquaintance when she matches the cognitive recognition (cognitive component) with the affective tone of familiarity (second component). When there is a lesion in the neural substrate of the affective component, she may recognize the face but without the tone of familiarity. In her effort to understand her affective experience of the face as alien rather than as familiar, she may conclude that her friend has been replaced by a double. Thus we have the Capgras delusion.Let us now unpack this explanation. According to Gerrans, researchers have hypothesized [End Page 61] two anatomatically distinct pathways involved in face recognition. He writes: "Initially... these separate neuroanatomic substrates were hypothesized to lie in separate dorsal and ventral processing pathways, but the most persuasive hypothesis is that of Breen et al. that face recognition is performed in the ventral visual processing pathway, whereas covert [affective] recognition effects result from the activation of pathways connecting the ventral pathway and the limbic system. It is damage to these latter pathways that gives rise to the Capgras delusion."In other words, the explanation of Capgras delusions depends on a neurocognitive model, itself based on an unspecified base of neuroanatomic data. When Gerrans writes that "[t]he Capgras delusion arises in cases where, following a neurological accident, the pathways connecting the FRU [Face Recognition Unit] to the limbic system are damaged leaving ventral pathways and hence overt recognition unimpaired...," he means that the Capgras delusion arises in that manner if the proposed model bears any relation to the reality of the living brain and if real Capgras patients have suffered the hypothesized lesion. At this point the reader is struggling with the following questions: (1) What are the hard neuroanatomic data underpinning the neurocognitive model? (2) What is the argument for developing this model (single Face Recognition Unit with independent pathways to cognitive and affective components of face recognition) out of the hard data? (3) What is the evidence... (shrink)

After the Second World War, a renaissance in field primatology took place in the United States under the aegis of the ‘new physical anthropology’. Its leader, Sherwood Washburn, envisioned a science uniting studies of hominid fossils with Darwinian population genetics, experimental functional anatomy, and field observation of non-human primates and human hunter–gatherers. Thanks to Washburn’s stimulus, his colleague at Berkeley, the bird ethologist Peter Marler, took up the study of the natural communicative behaviour of apes and monkeys. When Marler’s first (...) primatological student, Thomas Struhsaker, reported in the mid-1960s that the vervet monkeys of Amboseli, Kenya, give acoustically distinct alarm calls to different predators, and respond to alarm calls as if to the sight of those predators, a debate broke out over whether the vervet calls thus function as names, translating as ‘leopard’, ‘eagle’ and ‘python’. Washburn and his students argued that no matter what the behavioural evidence, vervet calls could not be predator names, since monkeys had been shown to lack the neuroanatomical basis of naming. This controversy thus reveals, first, the persistence of older patterns of disciplinary allegiance within the new, synthetic physical anthropology; and second, the impotence of adaptationist Darwinism — common to both sides of the debate — as a force for unity. (shrink)

This article argues for the gestural origins of speech and language based on the available evidence gathered in humans and nonhuman primates and especially from ape studies. The strong link between motor functions and speech in humans is reviewed. The presence of asymmetrical cerebral organization in nonhuman primates along with functional asymmetries in the perception and production of vocalizations and in intentional referential gestural communication is then emphasized. The nature of primate communicatory systems is presented, and the similarities and (...) differences between these systems and human speech are discussed. It is argued that recent findings concerning neuroanatomical asymmetries in the chimpanzee brain and the existence of both mirror neurons and lateralized use of hands and vocalizations in communication necessitate a reconsideration of the phylogenic emergence of the cerebral and behavioral prerequisites for human speech. (shrink)

On the basis of knowledge prior to 1988, Ashbrook pointed out that whereas most men are primarily dependent on the left cerebral hemisphere (“dominant hemisphere”) for verbally related functions, women show a greater hemispheric balance in this respect. For men, he argues, their possession of a “speaking” and a “non‐speaking hemisphere” results in a positive‐negative, bipolar way of thinking that may be characterized as dualistic and dialectically hierarchical. In contrast, the greater balance of hemispheric function in women appears to promote (...) greater generalization and synthesis in their thinking.In this article I cite more recent neuroanatomical and brain imaging studies that provide further evidence of disparities in structure and function of the brains of men and women. As background for an attempt to explain these differences, I give a brief review of the triune evolution of the mammalian brain leading up to the human cerebrum. It is of major significance that the female has played a central role in mammalian evolution for more than 180 million years and that the evolutionary transition from reptilian therapsids to mammals is characterized by the develoment of (1) nursing conjoined with maternal care; (2) audiovocal communication or aiding mother‐offspring contact; and (3) play. In human beings, the infant‐carrying hypothesis suggests one means by which, over generations, certain parts of a woman's right hemisphere could undergo functional and eventual anatomical expansion. The mother‐infant communication of basic mammalian sounds with vowel and consonant components suggests a basis for the origination of speech.Finally, in an expansion of Ashbrook's original thesis, we arrive at the rovocative consideration that, unlike men, with their dialectical reasoning, women, with their more balanced brain, are provided with a trialectial ladder for climbing to achieve knowledge. In terms of quantum mechanics, the particle and wave would correspond to the substance and strength of the sides of the ladder, and the derived psychic information (which is neither matter nor energy) would compare to the rungs in between. (shrink)

Hindbrain development is orchestrated by a vertebrate gene regulatory network that generates segmental patterning along the anterior–posterior axis via Hox genes. Here, we review analyses of vertebrate and invertebrate chordate models that inform upon the evolutionary origin and diversification of this network. Evidence from the sea lamprey reveals that the hindbrain regulatory network generates rhombomeric compartments with segmental Hox expression and an underlying Hox code. We infer that this basal feature was present in ancestral vertebrates and, as an evolutionarily (...) constrained developmental state, is fundamentally important for patterning of the vertebrate hindbrain across diverse lineages. Despite the common ground plan, vertebrates exhibit neuroanatomical diversity in lineage‐specific patterns, with different vertebrates revealing variations of Hox expression in the hindbrain that could underlie this diversification. Invertebrate chordates lack hindbrain segmentation but exhibit some conserved aspects of this network, with retinoic acid signaling playing a role in establishing nested domains of Hox expression. (shrink)

The capacity to extract socially relevant information from faces is fundamental to normal reciprocal social interactions and communication. The psychophysical evidence reviewed here demonstrates that humans possess a perceptual apparatus sensitive enough to detect the visual features which are informative of gaze in many face-to-face situations. This article provides evidence for the existence of three functionally and neuroanatomically dissociable eye gaze processing systems. Eye gaze also represents a class of biological motion cues, which engage the posterior superior temporal (...) sulcus for the analysis of intentions and psychological dispositions. Outputs from the anterior superior temporal sulcus constrain processing in the pSTS, linking the observed direction of gaze towards an object or person in the environment with the mentalistic information provided by the gaze shift. A few promising research directions for the field are highlighted. (shrink)

There are at least two different aspects of our rational evaluation of agents’ doxastic attitudes. First, we evaluate these attitudes according to whether they are supported by one’s evidence (substantive rationality). Second, we evaluate these attitudes according to how well they cohere with one another (structural rationality). In previous work, I’ve argued that substantive and structural rationality really are distinct, sui generis, kinds of rationality – call this view ‘dualism’, as opposed to ‘monism’, about rationality – by arguing that (...) the requirements of substantive and structural rationality can come into conflict. In this paper, I push the dialectic on this issue forward in two main ways. First, I argue that the most promising ways of resisting the diagnosis of my cases as conflicts still end up undermining monism in different ways. Second, supposing for the sake of argument that we should understand the cases as conflicts, I address the question of what we should do when such conflicts arise. I argue that, at least in a prominent kind of conflict case, the coherence requirements take precedence over the evidential requirements. (shrink)

Any attempt to elucidate the nature and mechanism of passivity phenomena, i.e., experiences that one’s conscious actions or thoughts have not been ‘willed’ by oneself, requires an integrative philosophical–neurobiological approach. The model proposed here adopts some fundamental positions that have long been advocated by philosophers and theoretical psychologists and have now found support from functional neuroanatomy. First, we experience our actions not from the standpoint of the executive but through the perception of its effects. Second, the ‘self’ is not an (...) agent of behaviour. Third, behaviour is energised and integrated by basic drives . Fourth, the view that the experience of an acting self is related to drive reduction associated with voluntary actions is perhaps less well developed. The model thus proposes that passivity phenomena are actions that are induced by the perception of salient events but that are not integrated with or conducive to the overall motivational state of the organism. It has been suggested that, following the perception of salient events, competition arises between automatic response tendencies seeking expression. The prefrontal cortex appears to play an important role not only in determining which events are to be perceived but also which of the corresponding response dispositions is to be selected and actualised in overt behaviour. Thus, action selection is the outcome of competition between response tendencies in the context of prefrontal biasing signals that represent drives and strivings for goals. Action selection may be uncoupled from drives and strivings as a result of a lowering of the threshold for action selection—as is suggested to be the case in schizophrenic passivity phenomena—or due to disconnection from prefrontal regions—as may be the case in the alien limb syndrome. (shrink)

Segregated neural circuits that effect particular domain-specific behaviors can be differentiated from neuroanatomical structures implicated in many different aspects of behavior. The basal ganglionic components of circuits regulating nonlinguistic motor behavior, speech, and syntax all function in a similar manner. Hence, it is unlikely that special properties and evolutionary mechanisms are associated with the neural bases of human language.

Many neuroanatomical alterations have been detected in patients with tinnitus in previous studies. However, little is known about the morphological and structural covariance network changes before and after long-term sound therapy. This study aimed to explore alterations in brain anatomical and SCN changes in patients with idiopathic tinnitus using voxel-based morphometry analysis 24 weeks before and after sound therapy. Thirty-three tinnitus patients underwent magnetic resonance imaging scans at baseline and after 24 weeks of sound therapy. Twenty-six age- and sex-matched (...) healthy control individuals also underwent two scans over a 24-week interval; 3.0T MRI and high-resolution 3D structural images were acquired with a 3D-BRAVO pulse sequence. Structural image data preprocessing was performed using the VBM8 toolbox. The Tinnitus Handicap Inventory score was assessed for the severity of tinnitus before and after treatment. Two-way mixed model analysis of variance and post hoc analyses were performed to determine differences between the two groups and between the two scans. Student-Newman-Keuls tests were used in the post hoc analysis. Interaction effects between the two groups and the two scans demonstrated significantly different gray matter volume in the right parahippocampus gyrus, right caudate, left superior temporal gyrus, left cuneus gyrus, and right calcarine gyrus; we found significantly decreased GM volume in the above five brain regions among the tinnitus patients before sound therapy compared to that in the HC group. The 24-week sound therapy group demonstrated significantly greater brain volume compared with the baseline group among these brain regions. We did not find significant differences in brain regions between the 24-week sound therapy and HC groups. The SCN results showed that the left superior temporal gyrus and left rolandic operculum were significantly different in nodal efficiency, nodal degree centrality, and nodal betweenness centrality after FDR correction. This study characterized the effect of sound therapy on brain GM volume, especially in the left superior temporal lobe. Notably, sound therapy had a normalizing effect on tinnitus patients. (shrink)

Common sense suggests that visual consciousness is essential to skilled motor action, but Andy Clark—inspired by Milner and Goodale's dual visual systems theory—has appealed to a wide range of experimental dissociations to argue that such an assumption is false. Critics of Clark's argument contend that the content driving motor action is actually within subjects' experience, just not easily discovered. In this article, I argue that even if such content exists, it cannot be guiding motor action, since a review of current (...) visual neuroscience indicates that the visual brain areas producing conscious representations are distinct from those driving motor action. (shrink)

Recent work in artificial intelligence has increasingly turned to argumentation as a rich, interdisciplinary area of research that can provide new methods related to evidence and reasoning in the area of law. Douglas Walton provides an introduction to basic concepts, tools and methods in argumentation theory and artificial intelligence as applied to the analysis and evaluation of witness testimony. He shows how witness testimony is by its nature inherently fallible and sometimes subject to disastrous failures. At the same time (...) such testimony can provide evidence that is not only necessary but inherently reasonable for logically guiding legal experts to accept or reject a claim. Walton shows how to overcome the traditional disdain for witness testimony as a type of evidence shown by logical positivists, and the views of trial sceptics who doubt that trial rules deal with witness testimony in a way that yields a rational decision-making process. (shrink)