A comparative neuropsychological approach to alcoholism and the brain

Comparative neuropsychology involves the study of brain-behavior relationships by applying experimental paradigms, used extensively in animal laboratories, for testing human clinical populations. Popular paradigms include delayed reaction tasks, discrimination and reversal learning tasks, and matching- and nonmatching-to-sample. Such tasks were perfected on experimental animals having well defined brain lesions, and adapted for the sensory and motor capabilities of human neurological patients. By holding task requirements constant for human and nonhuman primates, analogous measures can be made of neurobehavioral deficits associated with specific brain damage. Human and nonhuman primates solve many so-called animal-learning tasks, in similar ways. Moreover, many tasks, despite their apparent simplicity, already have proven to be sensitive to cognitive impairments after brain damage in humans and nonhumans alike. An important advantage of using paradigms from comparative neuropsychology, in conjunction with standard clinical neuropsychological assessments, is that the simplicity of the tasks makes them manageable for patients with severe cognitive impairments. In addition, since the tasks do not require linguistic strategies for performance, the problems can be solved by patients whose language skills are compromised. An example of the application of comparative neuropsychology to clinical populations is given: patients with a history of long term alcohol abuse were tested on delayed reaction paradigms, and the findings have been useful in clarifying the contribution of damaged frontal cortical-subcortical brains systems to their cognitive impairments.