[Effect of task complexity on cerebral organic reaction impairments--brain damage or patient effect?]

The contradictory results concerning the influence of task complexity on reaction time impairments following brain damage were reconsidered in this study. Patients with damage of the right or left cerebral hemispheres, as well as neurological patients without CNS lesions and normal controls were examined by four reaction tasks of varying complexity, a simple visual or auditory task and a choice reaction task. While there was no statistical interaction between the task-complexity and group effects for the brain-damaged and non-brain-damaged patients, comparison of the performance of brain-damaged patients and normal controls revealed such an interaction. Furthermore, the patients with damage of the right cerebral hemisphere showed a more distinct impairment of reaction time with the simple visual reaction task, while the patients with damage of the left cerebral hemisphere showed a more distinct impairment with the choice reaction task. These results are discussed in connection with several self-evaluations of the patients' performance and state of health.