Neuropsychology

neuropsychology

Science concerned with the integration of psychological observations on behaviour with neurological observations on the central nervous system (CNS), including the brain. The field emerged through the work of Paul Broca and Carl Wernicke (1848–1905), both of whom identified sites on the cerebral cortex involved in the production or comprehension of language. Great strides have since been made in describing neuroanatomical systems and their relation to higher mental processes. The related field of neuropsychiatry addresses itself to disorders such as aphasia, Korsakoff syndrome, Tourette syndrome, and other CNS abnormalities. See also laterality.

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neuropsychology [¦nu̇r·ō·sī′käl·ə·jē]

(psychology)

A system of psychology based on neurology.

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Neuropsychology 

the branch of psychology that studies the cerebral basis of mental processes and the relation of the processes to the individual systems of the brain. Neuropsychology first developed as a subdivision of neurology.

Over the centuries, idealistic psychology was either based on the assumption that physiological processes and conscious, or mental, processes are parallel or on assumptions about the interaction between physiological and mental processes, which were considered to be independent of each other. It was not until the second half of the 19th century that progress in the study of the brain and advances in the development of clinical neurology raised a question as to the role of the individual regions of the cerebral cortex in mental activity. Noting that such mental processes as vision, hearing, speech, writing, reading, and counting are impaired in man when certain regions of the left hemisphere (which is dominant) of the cortex are injured, neurologists assumed that these cortical regions are the physical centers of the impaired mental processes. In other words, early researchers assumed that mental functions are localized in certain bounded regions of the brain. These assumptions were subsequently elaborated into a formal theory. However, this “psychomorphological” approach was oversimplified.

Modern neuropsychology assumes that the complex forms of mental activity that took shape over the entire course of social development and that represent the most highly developed conscious reflections of reality are not localized in narrowly limited regions, or centers, of the cortex; rather, mental activity is realized through complex functional systems in which jointly operating cerebral regions take part. Each portion of the brain contributes a specific component to this functional system. For example, the brainstem and reticular formation maintain the attentiveness of the cortex and contribute to the maintenance of the waking state. The temporal, parietal, and occipital regions of the cortex constitute an apparatus that receives, processes, and stores modality-specific information. Auditory, tactile, and visual signals reach the primary division of each cortical region, are processed in the more complex “secondary” divisions of these regions, and then are combined and synthesized in “tertiary” zones. Tertiary, or “overlapping,” zones are especially well developed in man.

The frontal, premotor, and motor regions of the cortex are functionally united to formulate complex intentions, to shape the plans and programs of activity by which these intentions are implemented, and finally, to realize such plans through a system of coordinated, constantly controlled movements. In this manner, the entire brain participates in the complex forms of mental activity.

Neuropsychology is crucial to an understanding of the mechanisms of mental processes. In addition, by analyzing the disruptions of mental activity that arise as a result of localized brain injuries, neuropsychologists can diagnose cerebral tumors, hemorrhages, and traumas more accurately. Neuropsychology is the basis for the psychological evaluation of a defect that results from a cerebral injury; it is also the basis for the rehabilitative training that is prescribed by neuropathologists and neurosurgeons.

In the USSR, neuropsychological research is conducted in some laboratories and neurological clinics, as well as in the neuropsychology subdepartment of the psychology department at Moscow State University. Foreign scientists, including H. L. Teuber and K. Pribram in the United States, B. Milner in Canada, O. Zangwill in Great Britain, H. Hécaen in France, and E. Weigel in the German Democratic Republic, have made major contributions to neuropsychology. Neuropsychological research problems are dealt with in such journals as Neuropsychologia, published in Oxford since 1963, and Cortex, published in Milan since 1964. An international society for neuropsychologists has been established.

REFERENCES

Luriia, A. R. Vysshie korkovye funktsii cheloveka, 2nd ed. Moscow, 1969.
Luriia, A. R. Osnovy neiropsikhologii. Moscow, 1973.
Tonkonogii, I. M. Vvedenie ν klinicheskuiu neiropsikhologiiu. Leningrad, 1973.
Ajuriaguerra, J., and H. Hécaen. Le Cortex cérébral. Paris, 1960.

A. R. LURIIA