Functional neuroimaging in neurology and psychiatry

How can functional neuroimaging be applied to clinical neurology and psychiatry? This article reviews selected contributions of functional neuroimaging to the clinical neurosciences. We review selected technical aspects of positron emission tomography, single photon emission tomography, and functional magnetic resonance imaging with a focus on the relative strengths and weaknesses of these techniques. Consumers of functional neuroimaging research are encouraged to consider the limitations of imaging techniques and theoretical pitfalls of cognitive task design when interpreting results of functional imaging studies. Then, we selectively review the contributions of functional neuroimaging to neurology and psychiatry, including the areas of epilepsy, stroke, chronic pain, schizophrenia, depression, and obsessive-compulsive disorder. Future directions of functional neuroimaging research are offered, with the emphasis that the best conclusions are informed by a convergence of research from functional neuroimaging, neurophysiological, and lesion studies.     

Integrating cognitive psychology, neurology and neuroimaging

In the last decade, there has been a dramatic increase in research effectively integrating cognitive psychology, functional neuroimaging, and behavioral neurology. This new work is typically conducting basic research into aspects of the human mind and brain. The present review features as examples of such integrations two series of studies by the author and his colleagues. One series, employing object recognition, mental motor imagery, and mental rotation paradigms, clarifies the nature of a cognitive process, imagined spatial transformations used in shape recognition. Among other implications, it suggests that when recognizing a hand's handedness, imagining one's body movement depends on cerebrally lateralized sensory-motor structures and deciding upon handedness depends on exact match shape confirmation. The other series, using cutaneous, tactile, and auditory pitch discrimination paradigms, elucidates the function of a brain structure, the cerebellum. It suggests that the cerebellum has non-motor sensory support functions upon which optimally fine sensory discriminations depend. In addition, six key issues for this integrative approach are reviewed. These include arguments for the value and greater use of: rigorous quantitative meta-analyses of neuroimaging studies; stereotactic coordinate-based data, as opposed to surface landmark-based data; standardized vocabularies capturing the elementary component operations of cognitive and behavioral tasks; functional hypotheses about brain areas that are consistent with underlying microcircuitry; an awareness that not all brain areas implicated by neuroimaging or neurology are necessarily directly involved in the associated cognitive or behavioral task; and systematic approaches to integrations of this kind.     

Intentional concepts in cognitive neuroscience

In this article, I develop an account of the use of intentional predicates in cognitive neuroscience explanations. As pointed out by Maxwell Bennett and Peter Hacker, intentional language abounds in neuroscience theories. According to Bennett and Hacker, the subpersonal use of intentional predicates results in conceptual confusion. I argue against this overly strong conclusion by evaluating the contested language use in light of its explanatory function. By employing conceptual resources from the contemporary philosophy of science, I show that although the use of intentional predicates in mechanistic explanations sometimes leads to explanatorily inert claims, intentional predicates can also successfully feature in mechanistic explanations as tools for the functional analysis of the explanandum phenomenon. Despite the similarities between my account and Daniel Dennett's intentional-stance approach, I argue that intentional stance should not be understood as a theory of subpersonal causal explanation, and therefore cannot be used to assess the explanatory role of intentional predicates in neuroscience. Finally, I outline a general strategy for answering the question of what kind of language can be employed in mechanistic explanations.     

The cognitive neuroscience of creativity

This article outlines a framework of creativity based on functional neuroanatomy. Recent advances in the field of cognitive neuroscience have identified distinct brain circuits that are involved in specific higher brain functions. To date, these findings have not been applied to research on creativity. It is proposed that there are four basic types of creative insights, each mediated by a distinctive neural circuit. By definition, creative insights occur in consciousness. Given the view that the working memory buffer of the prefrontal cortex holds the content of consciousness, each of the four distinctive neural loops terminates there. When creativity is the result of deliberate control, as opposed to spontaneous generation, the prefrontal cortex also instigates the creative process. Both processing modes, deliberate and spontaneous, can guide neural computation in structures that contribute emotional content and in structures that provide cognitive analysis, yielding the four basic types of creativity. Supportive evidence from psychological, cognitive, and neuroscientific studies is presented and integrated in this article. The new theoretical framework systematizes the interaction between knowledge and creative thinking, and how the nature of this relationship changes as a function of domain and age. Implications for the arts and sciences are briefly discussed.     

The cognitive neuroscience of auditory distraction

We are often aware of the content of distracting sound, although typically remain unaware of the processes by which that sound is disruptive. Disruption can occur even when the sound is ignored and unrelated to the task being performed. In a recent major development, Gisselg?rd et al. have used positron emission tomography to reveal how distracting sounds recruit the involvement of dorsolateral prefrontal cortex.     

The emergence of social cognitive neuroscience

Social cognitive neuroscience is an emerging interdisciplinary field of research that seeks to understand phenomena in terms of interactions between 3 levels of analysis: the social level, which is concerned with the motivational and social factors that influence behavior and experience; the cognitive level, which is concerned with the information-processing mechanisms that give rise to social-level phenomena; and the neural level, which is concerned with the brain mechanisms that instantiate cognitive-level processes. The social cognitive neuroscience approach entails conducting studies and constructing theories that make reference to all 3 levels and contrasts with traditional social psychological and cognitive neuroscientific research that primarily makes reference to 2 levels. The authors present an introduction to and analysis of the field by reviewing current research and providing guidelines and suggested directions for future work.     

The cognitive neuroscience of signed language

The present article is an assessment of the current state of knowledge in the field of cognitive neuroscience of signed language. Reviewed lesion data show that the left hemisphere is dominant for perception and production of signed language in aphasics, in a fashion similar to spoken language aphasia. Several neuropsychological dissociations support this claim: Non-linguistic visuospatial functions can be dissociated from spatial functions and general motor deficits can be dissociated from execution of signs. Reviewed imaging data corroborate the lesion data in that the importance of the left hemisphere is re-confirmed. The data also establish the role of the right hemisphere in signed language processing. Alternative hypotheses regarding what aspects of signed language processing are handled by the right hemisphere are currently tested. The second section of the paper starts by addressing the role that early acquisition of signed and spoken language play for the neurofunctional activation patterns in the brain. Compensatory cognitive and communicative enhancements have also been documented as a function of early sign language use, suggesting an interesting interaction between language and cognition. Recent behavioural data on sign processing in working memory--a cognitive system important for language perception and production suggest e.g. phonological loop effects analogous to those obtained for speech processing. Neuroimaging studies will have to address this potential communality.     

Working towards a new psychiatry - neuroscience, technology and the DSM-5

This Editorial introduces the thematic series on 'Toward a New Psychiatry: Philosophical and Ethical Issues in Classification, Diagnosis and Care' .