Abstract

Schizophrenia patients often present with neurological signs such as left/right confusion, impaired coordination of movements, and motor abnormalities may occur secondary to antipsychotic medications. Neuropsychological tests identify various dysfunctions, such as difficulty in focusing attention, difficulty in abstract thinking or difficulty in changing the response frame, while Neurophysiological tests show slowing down of reaction time, problems with eye tracking, etc. There are no studies in the international literature dealing with the investigation of mental imagery of movement in Greek patients with schizophrenia. Also, the position that patients with schizophrenia – regardless of their symptom profile, age, sex, and chronicity of the disease – have a permanent difficulty in creating and manipulating an internal model of their movement prediction has not been substantiated enough to date.

Introduction

Neuropsychological deficits are recognized as primary symptoms of psychotic disorders, since they are detected even in the early stages, with some of them showing a more significant decline (e.g. executive functions, memory, attention) and others a smaller but significant one (e.g. language , movement perception, psychomotor). A wealth of neuropsychological research over the past decade has contributed to elucidating the nature and significance of cognitive dysfunction in schizophrenia. Today we know that patients with schizophrenia show lower performance in all known neuropsychological tests compared to healthy controls.

Materials and Methods

Based on the preceding literature review, it became clear that patients with schizophrenia present many cognitive deficits, the most important of which are related to executive functions, memory, and attention. The aim of our own research was to investigate the target-directed movement ability of the dominant hand of schizophrenics and to compare this ability with healthy individuals in order to clarify the possible difference between the two groups. Our research question has not been answered in any research in the Greek area and we hope that it will be another important element in being able to clarify with the greatest possible precision the deficits in the cognitive functions of schizophrenic patients.

Results and Discussion

Regarding gender, the sample consists of 42 men (46.7%) and 48 women (53.3%). Regarding the disease, 51 normal (56.7%) and 39 patients with schizophrenia (43.3%) participated. Of all the participants in the research, 2 people had completed primary education (2.2%), 12 people (13.3%) high school, 23 people high school (25.6%) 37 people (41.1%) the university while 16 people had also completed postgraduate education (17.8%). 27 people (30%) were aged 19 to 29, 19 people (21%) were aged 30 to 39, 12 people (13%) were aged 40 to 49, 23 people (26%) were aged 50 to 59 and 9 people (10%) belonged to the age group of 60 to seventy years.

Conclusion

The execution time of both real and mental movement in all subtests (target size) is longer for patients with schizophrenia compared to the corresponding times of normal subjects.

As the dimension of the target increases, the time to achieve the movement decreases for both conditions (real and mental movement) and for both groups (normal population - patients with schizophrenia).

Schizophrenia patients show larger differences between the mean execution time between the actual and mental execution of the movement than the corresponding differences of the normal population.

The difference in the averages of the time to achieve the movement is smaller between the two groups (normal - schizophrenic) for the condition of mental execution of the specific movement.

References

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