[Changes in psychological performance parameters of concentration and critical flicker-fusion frequency with...

Psychometric performance parameters and the critical flicker-fusion frequency are studied in various groups and in patients with chronic cerebral circulation trouble. Test d2 proves to be effective in the measuring of such impaired performance. There is a higher degree of correlation with Paul's addition test. A correlation between the performance parameters and the patient's age can be statistically substantiated. Among patients up to one third in the age group 55 and over show and affection of the cerebral performance turbances in spite of the absence of pathological clinical findings. The figure is twice as high in the group of patients undergoing treatment. The increased occurrence in old age shows the significance of pathological processes. There appears to be no relationship between critical flicker-fusion frequency and performance and stress factors. Individual correlations would support other physiological relations, such as an at present only hypothetical link with the psychic state (nervousness) of the test person. Our tables are suitable for practical purposes.