Does functional neuroimaging solve the questions of neurolinguistics?

Neurolinguistic research has been engaged in evaluating models of language using measures from brain structure and function, and/or in investigating brain structure and function with respect to language representation using proposed models of language. While the aphasiological strategy, which classifies aphasias based on performance modality and a few linguistic variables, has been the most stable, cognitive neurolinguistics has had less success in reliably associating more elaborately proposed levels and units of language models with brain structure. Functional imaging emerged at this stage of neurolinguistic research. In this review article, it is proposed that the often-inconsistent superfluity of outcomes arising from functional imaging studies of language awaits adjustment at both "ends" of the process: model and data. Assumptions that our current language models consistently and reliably represent implicit knowledge within human cerebral processing are in line for major revision; and the promise of functional brain imaging to reveal any such knowledge structures must incorporate stable correlates of the imaging signal as dependent variable.     

Generative models, brain function and neuroimaging

The representational capacity and inherent function of any neuron, neuronal population or cortical area in the brain is dynamic and context-sensitive. Functional integration, or interactions among brain systems, that employ driving (bottom up) and backward (top-down) connections, mediate this adaptive and contextual specialisation. A critical consequence is that neuronal responses, in any given cortical area, can represent different things at different times. This can have fundamental implications for the design of brain imaging experiments and the interpretation of their results. Our arguments are developed under generative models of brain function, where higher-level systems provide a prediction of the inputs to lower-level regions. Conflict between the two is resolved by changes in the higher-level representations, which are driven by the ensuing error in lower regions, until the mismatch is "cancelled". From this perspective the specialisation of any region is determined both by bottom-up driving inputs and by top-down predictions. Specialisation is therefore not an intrinsic property of any region but depends on both forward and backward connections with other areas. Because the latter have access to the context in which the inputs are generated they are in a position to modulate the selectivity or specialisation of lower areas. The implications for classical models (e.g., classical receptive fields in electrophysiology, classical specialisation in neuroimaging and connectionism in cognitive models) are severe and suggest these models may provide incomplete accounts of real brain architectures. Here we focus on the implications for cognitive neuroscience in the context of neuroimaging.     

Transcranial magnetic stimulation as a tool for cognitive studies

Transcranial Magnetic Stimulation (TMS) is a tool for the non-invasive stimulation of the human brain. It allows the activation of arbitrary sites of the superficial cortex and, combined with other brain-imaging techniques such as EEG, PET, and fMRI, it can be used to evaluate cortical excitability and connectivity. This is of major importance in, for example, the study of cognitive processes such as language, learning, memory and self-representation, which are thought to be represented in multiple brain areas. The mechanisms of action of TMS are known on a basic level, but its effect on the activation state of brain tissue is still poorly understood. Clinical applications of TMS have also been proposed and guidelines for its safe use drafted.     

从面孔模块到马赛克──视觉特异性加工的脑机制

“脑功能的模块性”是视觉乃至整个认知神经科学的研究热点。特异性的面孔加工模块被当作是认知模块假说的最好证据。但综述跨学科的正反两方面实验证据表明,视觉加工存在特异性,并没有普遍的模块式的亚单元,而是“马赛克”镶嵌式的组构。     

左前额叶参与非相关词对的语义编码过程──来自光学成像的佐证

通过研究左前额叶在非相关同对的语义编码过程中的作用,探讨近红外光学成像技术用于脑高级认知活动检测的可行性。被试在两种实验条件下分别学习视觉呈现的20个汉字非相关词对,要求被试或将词对组成一个有意义的句子(深加工),或判断两个词是否具有相同的结构组合(浅加工)。光学成像器即时记录连续光透过额骨及前额皮层后760nm和850nm的漫射光强变化,以此推测相应脑组织的血容量变化。结果表明,与浅加工相比,左下前额叶在深加工时的血容量增多,尤其是背外侧部分。     

Understanding Biology in Religious Experience: The Biogenetic Structuralist Approach of Eugene d'Aquili and Andrew Newberg

What are the biological bases of religious experience? Are there biological constraints upon or determinants of religious narratives and practices? How does understanding the biology of religious experience inform the ongoing reconstruction of religious rituals and myths? In The Mystical Mind, Eugene d’Aquili and Andrew Newberg address these central questions and others from a distinct perspective called biogenetic structuralism. They propose a model of how brain activity gives rise to mystical experiential states, examine how neurobiological responses to rhythmic behavior form religious ritual, and point toward the development of a megatheology, or a theological system appealing to the widest scope of religious world‐views. This paper is a critical review of d’Aquili and Newberg's exciting work.     

The Biological Basis of Social Interaction

The fact that brain disorder can impair social interactions in different ways suggests that social competence has multiple components that have foundations in brain systems. The physiological basis of one aspect of social cognition, theory of mind, is just beginning to be understood. Brain-imaging studies suggest that a network of areas linking medial prefrontal and temporal cortex forms the neural substrate of mentalizing, that is, representing one's own and other people's mental states. The medial prefrontal areas are prominent also in tasks that involve self-monitoring, whereas the temporal regions are prominent also in tasks that involve the representation of goals of actions. We speculate that the precursors of mentalizing ability derive from a brain system that evolved for representing agents and actions, and the relationships between them.     

Functional integration and the mind

Different cognitive functions recruit a number of different, often overlapping, areas of the brain. Theories in cognitive and computational neuroscience are beginning to take this kind of functional integration into account. The contributions to this special issue consider what functional integration tells us about various aspects of the mind such as perception, language, volition, agency, and reward. Here, I consider how and why functional integration may matter for the mind; I discuss a general theoretical framework, based on generative models, that may unify many of the debates surrounding functional integration and the mind; and I briefly introduce each of the contributions.     

Hemispheric asymmetries in visual word-form processing: progress, conflict, and evaluating theories

The ubiquitous left-hemisphere advantage in visual word processing can be accounted for in different ways. Competing theories have been tested recently using cAsE-aLtErNaTiNg words to investigate boundary conditions for the typical effect. We briefly summarize this research and examine the disagreements and commonalities across the theoretical perspectives. This work may provide a good example why a multi-level, multi-method, and multi-paradigm approach holds the greatest promise for rapid theoretical progress.