This paper evaluates task complexity as a task-related factor causing the development of psychologically mediated ('psychogenic') shoulder muscle tension. Eighteen subjects performed an experimental work session, responding to simple and complex reaction time tasks which were presented on a VDU screen. Most subjects generated low-level static muscle tension during the tests. On a group level the two tasks did not have a differential effect on muscle tension. However, a subgroup of eight subjects which consistently generated higher muscle tension in the complex tests, was identified. It is argued that for these subjects the difference in muscle tension is due to an increased mental effort invested, because of the higher computational demands in the complex task.

This paper evaluates motivation as a task-related factor causing the development of psychologically mediated ('psychogenic') shoulder-muscle tension. In four separate experiments using a visual display unit (VDU) based complex reaction-time task, motivation was established by means of continuous feedback on the level of performance (relative to a preset target performance level) or by means of a money reward for good performance. In all experiments motivation improved the performance, but an increase in the psychogenic shoulder-muscle tension was only observed in the money-reward condition. It is discussed whether this difference in the muscle-tension response is due to changes in the subjects' attitude unrelated to performance or due to a superior performance in the money-reward condition.

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This study intends to assess the effect of long-term training on police officers' use of open and closed questions in investigative interviews of children. One hundred field investigative interviews of children were divided into two groups based on the interviewers' level of competence (training and experience). The police officers' questions were classified into groups of either open or closed. In all interviews, the mean numbers were 20 open and 217 closed questions, corresponding to an open-closed question

In an attempt to develop a short neuropsychological test battery five different tests of reaction time were assessed according to their ability to discriminate between HIV seropositive men and healthy controls. In all tests a patient group with clinical symptoms was slower than the control group. In the complex reaction time test, which has a large cognitive aspect, even a clinically "asymptomatic" group was slower than the control group. The movement test, a new test with a large motor component, identified most slow responders, defining approximately half of the patients with clinical symptoms and one third of the "asymptomatic" patients as such. A test battery consisting of three tests is suggested for serial assessment and screening.