Journal of Mental Science (1955) 101: 354-362. doi: 10.1192/bjp.101.423.354
© 1955 The Royal College of Psychiatrists
Dark Adaptation in Neurotic Patients
G. W. Granger, Ph.D.
Psychological Department, Institute of Psychiatry Maudsley Hospital, London, S.E.5
ABSTRACT
- The object of this experiment was to determine if neurotic patients showed an impairment in their absolute light thresholds over the rod portion of the dark adaptation curve.
- Twenty normal subjects and twenty neurotic patients were tested using the Crookes Adaptometer and mean dark adaptation curves plotted for the two groups.
- Differences ranging from 0.2 to 0.5 log units (µµl) at different periods of adaptation were found, the neurotics having higher thresholds than the normals at all points of the rod adaptation curve.
- Scatter about the means, however, was considerable, particularly in the neurotic group whose average standard deviation was about 0- 3 log units, and an examination of individual curves was therefore undertaken.
- This analysis revealed differences within the neurotic group that appeared to be related to diagnostic category. Plateau effects in the adaptation curve seemed to be associated with anxiety states rather than with hysterics or psychopaths; high final thresholds with hysterics, and low thresholds with psychopaths.
- As a result of these observations it was considered that further research should be undertaken with another group of neurotic patients in which each of the various sub-categories was more adequately represented.