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This chapter gives a demonstration of how different incidences of scanning modify the anatomical appreciation of structural brain lesions. Examples include lesions in left parietal, left calcarine, right temporal, and left frontal regions.

This chapter reviews current knowledge of the neurobiological regulation of affiliative, aggressive, sexual, and parental behavior in nonhuman primates. It focuses on social behavior expressed in the context of interactions between two or more individuals. It begins by reviewing research on the neurochemical control of primate social behavior, particularly studies of endogenous opioids, oxytocin and vasopressin, and the brain monoamine systems. It then considers the results of brain lesion studies investigating the neural substrates of primate social behavior. The chapter concludes by summarizing the main trends emerging from this literature review, and by discussing future research directions.

Memory is composed of multiple dissociable systems, varying according to the length of retention interval, level of consciousness, and modality of information to be learned. Memory systems are differentially affected in amnesia, depending from localization and aetiology of brain lesions. One of the main dissociations in memory concerns the duration of storage systems. Short-term memory holds information active in the mind over limited time periods, while long-term memory stores information durably. Dissociation of these systems is common in amnesia. Amnesic patients tend to show relatively preserved short-term memory, but fail to encode information into a more durable and stable trace.

The term ‘behavioural’ is often used in neurology to denote non-cognitive mental symptoms or disorders, thus including many psychiatric symptoms such as mood and psychotic disorders but also abnormal personality traits such as impulsivity and aggression or even social isolation. However, this chapter focuses on a more operational and restricted definition of this term. In psychology, the notion of behaviour includes the responses or reactions of an individual in front of a stimulus or in a given environment. The mechanisms by which brain lesions can affect a patient's behaviour depend on the pathogeny of lesions but also on their localization. In the acute case, altered perceptual and mental states can mimic confusional states and delusional symptoms. In the more chronic states, different deficits can modify behavioural response after stroke, and these causes correspond to the different steps that will lead to the patient's reaction.

The behavioural data reviewed in the chapters came mainly from the effects of brain lesions. The chapters were written before the invention of positron emission tomography (PET) or functional magnetic resonance imaging (fMRI) for imaging the human brain at work. Researchers now know much more about the functional organization of the human brain from imaging studies, and it is time for a reappraisal. This chapter is an attempt toward this end.

This chapter examines the nature of the human brain dysfunction and how it contributes to changes in aggressive behaviour using data from lower animal research. It explains that the brain mechanisms of humans and lower animals are similar, especially at the subcortical level. The findings reveal that brain lesions caused by tumours or illness may result in increased aggression, while seizure disorders are generally not associated with increased aggression.

This chapter first outlines the processes and information involved in making episodic representations at encoding and considers the underlying brain regions. Second, major views about the psychological and physiological processes underlying consolidation and long-term storage of episodic representations are outlined and differing views concerning where these processes are located in the brain are discussed. Third, views about how retrieval is achieved and the feeling that retrieved episodes are being remembered is examined. Which brain structures mediate these processes are discussed. Where relevant, the similarities and differences between episodic memory and both semantic memory and priming are discussed whilst these theories are assessed. Each section highlights where there are theoretical disagreements, or processes and their neural bases that have been poorly specified, and considers how lesion and functional neuroimaging research is helping with theory development in these problem areas.

This chapter describes the elementary component of motor cognition — action representation. A historical survey of the early attempts at answering the question of the embodiment of action representations leads back to the early days of neuropsychology: description of apraxia in brain-lesioned patients gave the first significant account of what can happen when action representations cannot be properly formed and handled. Functional models of action representations are discussed.

This chapter addresses the basis for general intelligence or Spearman's g. It begins with a striking finding from functional brain imaging: in specific regions of frontal and parietal cortex, there is a pattern of similar activation for many different cognitive demands. Plausibly, this pattern of multiple-demand (MD) activity could reflect functions basic to g. A related finding comes from monkey studies: in the lateral prefrontal cortex, neurons produce a dense, selective representation of information relevant to a current task, whatever that task may be. Moving on to behavioural studies, the discussion shows how competition in a task model can result in loss of vulnerable task components. It ends with evidence from an ongoing study of human brain lesions. Though MD damage is associated with g deficits, such deficits can also be produced by large lesions elsewhere.

This chapter addresses the temporal processing of complex sounds relevant to musical analysis. Functional imaging studies, using positron emission tomography (PET), functional magnetic resonance imaging (fMRI), and magnetoencephalography (MEG), and the psychophysical assessment of patients with lesions allow two different approaches to this. Functional imaging allows the determination of structures normally involved in temporal analysis, while patient studies allow inference about the necessary structures for temporal analysis. Both approaches suggest a hierarchal organization in the brain corresponding to the processing of music. The features of individual notes are analyzed in the pathway up to and including the auditory cortices, while higher-order patterns formed by those features are investigated by distributed networks in the temporal lobe and frontal lobes distinct from the auditory cortices. Both studies of humans with brain lesions and functional imaging provide convergent evidence for the existence of a neural substrate for the processing of sound sequences that is hierarchal in organization.

This chapter provides a crude overview of current knowledge in neuroscience about the human nervous system and its functionality. The distinction between the peripheral and central nervous systems is introduced. Next, brain anatomy is introduced, as well as nerve cells and the information processing principles that unfold in biological neural networks. Moreover, brain modules are covered, including their interconnected communication. With modularizations and wiring systematicities in mind, functional and structural systematicities are surveyed, including neural homunculi, cortical columnar structures, and the six-layered structure of the cerebral cortex. Finally, different available brain imaging techniques are contrasted. In conclusion, evidence is surveyed that suggests that the brain can be viewed as a highly modularized predictive processing system, which maintains internal activity and produces internal structures for the purpose of maintaining bodily needs in approximate homeostasis.

The various neural networks of the infant brain do not all become functional at the same rate. Investigating the relationships between emerging cognitive competences and maturational neural events can therefore be most instructive. In some respects, this approach to the neural basis of behaviour, although it involves some methodological difficulties, is similar to the neuropsychological approach to adult patients with brain lesions. The double dissociations between emerging behaviours and between neural maturational events correspond to the double dissociations that are being studied in adult patients. Neural events of other kinds, which may be very similar or even identical to those underlying adult learning processes, are probably involved in the mechanisms of cognitive development. Discovering how learning mechanisms and neural maturation co-operate and are correlated with age-related behavioural changes is the main goal of the developmental approach.

The MMN amplitude is decreased and/or peak latency prolonged in a large number of different neurological disorders, such as neurodegenerative diseases, brain lesions, cochlear lesions, chronic pain, or tinnitus. This is to a great extent due to a decreased brain plasticity affecting the formation of memory traces for different sensory stimuli essential for different cognitive operations of the brain. Furthermore, MMN can serve as a measure of recovery or neural reorganization in different neurological disorders. For example, the recovery from aphasic symptoms after stroke was associated with the enhancement of MMN. MMN has also been useful in determining neural plastic changes of the auditory system associated with cochlear implantation.

Imaging is one of the major tools for neuroscience but it should be seen against the background of neuroscience in general. The brain can be studied by charting its connections, by recording its activity, or by intervening in its workings. In animals the connections can be demonstrated by tracer techniques, recordings can be taken of the activity of single cells, and lesions can be placed in selective cytoarchitectonic areas. Brain imaging provides methods for studying the human brain. Connections can be inferred using diffusion weighted imaging, activations can be recorded using functional magnetic resonance imaging, and transcranial magnetic brain stimulation can be used to intervene. The development of these methods has provided the means for studying the neural basis of cognitive abilities, including those that are unique to the human brain.

This chapter reviews neuropsychological evidence, from patients with selective brain lesions, indicating that there can be several kinds of binding in vision. Damage to early processes within the ventral visual stream impairs the binding of contours into shapes. This impairment can leave unaffected a more elementary operation of binding form elements into contours. Thus the process of binding elements into a contour is distinct from the process of binding contours into more holistic shapes. In other patients with damage to the parietal lobe, there can be poor binding of shape to surface information in objects. This problem in turn can coexist with a relatively intact process of binding contours into shapes. These findings suggest that there are multiple stages of binding in vision, including binding to derive shape descriptions and binding shape and surface detail together. This chapter concludes that the unity of consciousness is derived from several separable neural processes of binding.

Animals played significant roles in Gall’s research program, in which he viewed humans as merely having more complex and better developed brains. Studying lowly animals, barnyard animals, wild animals, and pets helped reveal what makes us human, both behaviorally and with regard to brain development, while providing a natural backdrop on which life can be viewed on a continuum (i.e., a Great Chain of Being, albeit one devoid of supernatural entities). Gall even compared animals to humans with brain injuries and diseases. Further, he was an animal lover who always had pets around him, and he did not hesitate to mention how observing animals, including his pet dogs, birds, and monkeys, helped him discover particular faculties and their locations. He also did everything he could to encourage people to send him stories of exceptional animals and, ideally, their heads or skulls when they died. He did not, however, look favorably on brain lesion experiments with animals, railing against such mutilations as having so many problems that they could not convey clear and reliable information. Nonetheless, he did conduct a few experiments of his own to see if the findings of others, including Pierre Flourens, could be verified.

Functional imaging is primarily a correlational technique. Although there are methods for analyzing the causal structure of systems, proof of causation requires methods that intervene in the workings of the system. If area A influences area B, preventing activity in A should diminish activity in B. The interference with activity in area A can be permanent, as after a brain lesion, or temporary, as with the application of transcranial magnetic stimulation. However, to understand the workings of the system we need to know not only that area A influences area B, but also how it does so. This involves the synchronization of activity in the two areas. To study this one needs methods such as electro-encephalography and magneto-encephalography that provide evidence of synchronized and dynamic oscillations at different frequencies.

This chapter has six subdivisions. The first section, A, discusses the basic facts about how different wavelengths in the visual range are processed. In section B the manner in which brain areas and individual neurons process wavelength information is delineated. In section C behavioral studies assessing the effects of specific brain lesions on color vision are described. Section D provides information about how perception is altered when only chrominance cues are available, a condition generally referred to as perception isoluminance. Section E provides information about color blindness. In section F a summary is provided.