The assessment of brain damage from a psychometric point of view

Continuous reaction times in cerebral dysfunction

The Continuous Reaction Times (CRT) method was used to examine pharmacological, psychiatric, medical and neurological problems in clinical practice where a detailed neuropsychological examination with a test battery was not possible. Either 100 visual or 150 auditory stimuli were given within a period of 6 1/2 or 10 min respectively, and the patients were instructed to react as quickly as possible to every stimulus. The same CRT method was applied to heterogeneous groups of patients with cerebral dysfunction and control subjects. The results demonstrated that it was useful as a screening test for the presence of cerebral dysfunction and was especially sensitive to progressive diseases. Its discriminative power was equivalent to more sophisticated and complex psychological tests. Even if CRT is a valid and reliable method of testing cerebral affection, the neural background for the reaction time process is still unknown and the test did not distinguish between patients with right- or left-hemisphere lesions and was not influenced by the etiology of the disease. CRT is therefore considered a provisional method, suggestive only for the actual diagnostic procedures. Only when the patients have a well-defined diagnosis e.g. a diffuse cerebral affection caused by a drug or a metabolic disorder can CRT be recommended as a measure of the degree of lowered consciousness.

Vocabulary deficit and abstraction impairment in hospitalized alcoholics

The use of a standard intelligence test for detecting cognitive impairment has been re-examined in a cohort of 506 hospitalized alcoholics. The value of Vocabulary scores as indicators of original intelligence was tested by formulating the hypothesis that Vocabulary scores would remain constant despite increasing degrees of alcohol-induced cerebral dysfunction. Subjects were assigned to non-dysfunctional, minimal and severe dysfunctional groups on the basis of psychometric testing and their Wechsler Vocabulary scores categorized as either 'abstract' 'concrete' or 'wrong'. Significant linear deficits in Vocabulary score and loss of abstract ability correlated with increasing dysfunction, irrespective of age but with greater frequency in females.

Problems in the clinical assessment of memory

The purpose of this paper is to examine the current state of clinical memory testing in the light of recent theoretical and experimental advances in the study of human memory. It recounts some of the purposes of memory testing and inadequacies in the tests currently available. A brief review of information processing theory and experimental findings with Korsakoff patients and aged normals provides a number of considerations that must be attended to in developing more adequate memory tests in the future.