Differences between the sexes in sensory sensitivity and performance in the visual and auditory modalities
50 young adult males and 50 females undertook a series of psychophysical experiments in the auditory and visual modalities, testing (i) sensory threshold, (H) the subjective response to intensity,· and (Hi) discriminatory ability (the Phase 1 experiments). Significant differences between the sexes in performance in the auditory modality were found in absolute threshold for some frequencies with females being more sensitive in each instance. In their subjective response to intensity in the auditory modality, females consistently set levels 8 - 9 dB lower than those set by males at all frequencies. In all instances the difference was statistically significant. No significant differences between the sexes were obtained in their ability to discriminate pitch. In the visual modality significant differences between the sexes are not apparent for dark adaptation (used as a test of threshold) or the subjective reaction to intensity (glare). Analysis of the visual acuity scores (discriminatory ability) shows a sex difference in favour of the males (p> 0.01). Extensive correlational analyses are employed to examine within-mode and inter-modality relationships. The lack of consistent significant and high relationships obtained indicate that sensory sensitivity is not a consistent property of the nervous system, and presents some problems for current theories of personality. The effects of the menstrual cycle on female performance in the auditory and visual modality tasks are also considered, and the data indicates that hormonal influences are implicated. Having established that some differences between the sexes do exist in the performance of visual and auditory tasks at the sensory or basic perceptual levels, the second phase experiments (administering the Bennett Differential Aptitude Tests) were commenced. The rationale and methodology for these experiments is described. Significant differences between the male and female groups in this study were not apparent in any of the Verbal/Language Usage tests, but significant differences in favour of the males were obtained for Space Relations (p.> 0.05) and Mechanical Reasoning (p>0.02). Correlational analyses between the auditory and visual parameters and the cognitive abilities tested on the. Bennett DAT showed high significant relationships (p > 0 .01) between auditory intensity tolerance and all the Verbal/Language Usage tests, and a significant relationship for the total sample (p >0·.05) between visual acuity and the Space Relations test. The implications of the data obtained in this study for existing theories of sex differences are discussed.