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This chapter reviews data from a single methodology—acute functional lesion-deficit correlation—that has been used to evaluate specific hypotheses regarding the neural basis of reading. The goal of this methodology is to determine those areas of the brain responsible for impairments of specific components of the reading process, before reorganization or recovery.

The hippocampus is one of the most thoroughly studied areas of the mammalian central nervous system. There are two main reasons for this. First, it has a distinctive and readily identifiable structure at both the gross and histological levels. A second reason for the interest in the hippocampus is that since the early 1950s, it has been recognized to play a fundamental role in some forms of learning and memory. This chapter discusses the general organization of the hippocampus, covering its neuronal elements, synaptic connections, physiological and pharmacological properties, neurotransmitter receptors, synaptic plasticity, dendritic properties, and functional operations.

The thalamus is the largest part of the diencephalon, one of the major subdivisions of the brain, and provides the major route for afferents to the neocortex. Essentially no messages can reach the neocortex without first passing through the thalamus. Messages from many different sources pass through the thalamus on the way to the neocortex, including messages from peripheral sense organs (such as vision, hearing, touch, temperature, pain, taste, olfaction), other regions of the brain (such as the cerebellum and the mamillary bodies), and the neocortex itself. This chapter discusses the general organization of the thalamus, covering its neuronal elements, synaptic connections, basic neuronal circuit, dendritic cable properties, membrane properties, synaptic transmission, and first order and higher order relays.

The basal ganglia are a richly interconnected set of brain nuclei found in the forebrain and midbrain of mammals, birds, and reptiles. In many species, including most mammals, the forebrain nuclei of the basal ganglia are the most prominent subcortical telencephalic structures. This chapter discusses the general organization of the basal ganglia, covering its neuronal elements, synaptic connections, basic circuit, dendritic membrane properties, and functional operations.

This chapter argues for the investigation of the hemisphere dominances of brain functions rather than structural, cellular, and molecular asymmetries in brains. Although the latter are certainly neural bases of perceptual and behavioral asymmetries generated in the brain, the relationships are largely unclear and most probably complicated in details. Such an approach has both an evolutionary perspective, asking for the common origin and advantages of hemisphere specializations of vertebrate brains, and a perspective of genetic and physiological mechanisms responsible for the realization of hemisphere specializations of certain kinds.

This chapter reviews the research that examines the brain more directly via brain imaging. The clinical implications of this research are significant. For instance, neuroimaging studies of psychopathy have implemented a variety of brain imaging techniques and paradigms to uncover the brain regions in which the structure or functioning is different in psychopathy. These studies primarily implicate the amygdala and orbitofrontal cortex as the brain structures that function differently in psychopathy, though several additional regions involved in important processes such as moral judgment have been identified. In addition, studies conducted through brain imaging in children with psychopathic traits suggest that alterations in the brain may originate early in life.

This chapter focuses on the structure and function of the microcircuits of the neocortex and their components. Topics covered include embryonic development, neuronal elements, synaptic connections, basic circuit, synaptic actions, neurotransmitters, dendrites, spines, and functional operations.

The cerebellum is a very distinct region of the brain, occupying a position immediately behind the tectal plate and straddles the midline as a bridge over the fourth ventricle. The basic functional design of the cerebellum is that of an interaction between two sets of different neuronal elements: those of the cortex and those in the centrally located cerebellar nuclei. The cerebellar cortex receives two types of afferents, the climbing fibers and the mossy fibers, and generates a single output system, the axons of Purkinje cells. The cerebellar nuclei receive collaterals from the climbing and mossy fibers and are the main targets for the Purkinje cell axons. The cerebellum as a whole is connected to the rest of the central nervous system by three large fiber bundles, the cerebellar peduncles. This chapter discusses the general organization of the cerebellum, covering its neuronal elements, synaptic connections, basic circuit organization, intrinsic membrane properties, synaptic actions, dendritic properties, and functional circuits.

Defining emotion is considered an extremely difficult task and there is hardly any concrete definition that positively leads to proper results from a study of the brain correlates of emotion. Imaging experiments signify that the brain regions associated with emotional activity most likely differ from study to study. These experiments reveal that almost every region of the brain is found to be operating in a coordinated fashion in any given emotional condition, and thus, it becomes difficult to single out any particular brain region for its actual role in an emotional function. The frontal lobes are found to be involved in emotional behavior to a great extent; the kind of role they play in emotion is not certain.

Many lines of research have demonstrated structural plasticity of dendrites in the mammalian brain. Historically, the concept of structural plasticity has been incorporated into theories of learning in which structural changes in synaptic connections between neurons are suggested to underlie long-term information storage. However, the fact that circuits encoding learned information are likely to be distributed within and between brain regions, combined with the inability to identify individual cells and synapses involved in learning, makes it difficult to test this hypothesis directly. Even so, a number of experiments have demonstrated consistent experience- or learning-dependent structural changes in dendrites and synapses of cortical structures.

This chapter focuses on the term “attention,” which is used in the context of psychological research. Several popular definitions of attention are presented along with definitions used by the scientific community to describe attention. However, the definitions presented do not actually define the exact meaning of attention as they revolve only around describing the characteristics or attributes of attention. The chapter discusses the components, types, and distinguishable varieties of attention along with the psychological research on it, which is divided into the classic stage and the modern stage. Different stages of the neuroscientific study of attention, including the classic stage and the stage of brain imaging, are presented. The classic stage study concluded that the complex interaction of different brain regions was associated with attention, which is endorsed by the brain imaging study.

Neuropsychological evidence and how it strengthens the case for considering spatial coding as dependent on the integration and organization of multimodal inputs is the main concern of this chapter. The evidence on anatomical and physiological changes is reviewed here. The chapter first provides a rough outline of some of the relevant brain regions and sensory systems. The other sections in this chapter focus on hemisphere specialization, especially for spatial processing in parietal regions of the right cerebral hemisphere, the effects of early experience, and the convergence of inputs in spatial functioning.

The hippocampus must be considered in the context of how it performs its functions within the larger system of brain structures of which it is a part. Indeed, the hippocampus is only one of several structures that compose the full brain system that mediates declarative memory. This chapter identifies the main components of this system, outlines the anatomical pathways by which information flows through the system, and characterizes the functional contributions of its different components.

This chapter aims to provide a detailed understanding of the processes underlying memory for different kinds of information and how the relevant brain structures mediate these processes. The chapter contends that different types of memory, which are dependent upon brain regions with very different anatomical organizations, are likely to rely upon different kinds of encoding, storage, and retrieval processes. Methods of distinguishing between different memory systems and processes are explored and then utilized by the chapter to interpret the ways in which different kinds of memory mediate. The chapter also highlights the importance of identifying the kinds of processes which mediate memory for different kinds of mnemonic information. A framework of four kinds of processes or mechanisms underlying long-term memory, which the chapter argues offers a processing approach to questions about putatively different kinds of memory system, is presented as well.

This chapter shows that new methods for measuring effective connectivity allow us to characterize the interactions between brain regions which underlie the complex interactions among different processing stages of functional architectures. It reviews the basic concepts of effective connectivity in neuroimaging. The methods introduced to assess effective connectivity are multiple linear regression, covariance structural equation modelling and variable parameter regression. The first example demonstrates that non-linear interactions can be characterized using simple extensions of linear models, while in the second, structural equation modelling is introduced as a device that allows one to combine observed changes in cortical activity and anatomical models. Finally, the chapter concludes that the approach to neuroimaging data and regional interactions is an exciting endeavour, which is starting to attract more attention.

This chapter shows that new methods for measuring effective connectivity allow one to characterize the interactions between brain regions. These regions underlie the complex interactions that occur among different processing stages.

An account of multiple memory systems in terms of functional dissociations within brain systems is presented in this chapter. Data from both the human and non-human literatures are considered. It focuses on five brain regions — hippocampus, amygdale, thalamus, prefrontal cortex, basal ganglia — that have been reliably identified with learning and memory processes. The aim is to show that, together, these regions comprise an array of integrated yet functionally dissociable neural circuits which is a critical aspect of learning and memory. It argues that memory should not be regarded as a unitary process, rather, it presents evidence that within the brain's complex organization, differentiated structures can be implicated in subserving specific components of learning and memory and that these functions can be dissociated using sensitive behavioural paradigms.

This chapter compares the effects of lesions to a single region of the chick brain, the intermediate part of the medial hyperstriatum ventrale (IMHV), on a number of behavioural tasks and discusses their implications for the function of IMHV. The results of experiments designed to investigate the effects of brain lesions on behaviour are difficult to interpret since they do not necessarily provide unambiguous information about the localization of function within the brain. Lesion studies have contributed greatly to the knowledge of the neural basis of learning in the chick. The key to understanding the differences in the function of IMHV in the tasks in which it is involved is likely to lie in the interaction of IMHV with other brain regions, known as filial imprinting – the process by which a chick learns to form a preference for the first visually conspicuous object to which it is exposed.