Biomedical subjects

Glenn D Wilson

Publications and source records attributed to Glenn D Wilson.

9 recordsLinked to original sources

PubMed2004

Sex, sexual orientation, and identification of positive and negative facial affect.

Sex and sexual orientation related differences in processing of happy and sad facial emotions were examined using an experimental facial emotion recognition paradigm with a large sample (N = 240). Analysis of covariance (controlling for age and IQ) revealed that women (irrespective of sexual orientation) had faster reaction times than men for accurate identification of facial emotion and were more accurate in identifying male faces than female ones, whereas men performed the same regardless of the sex of the face. However, there were no overall sex differences in accuracy. These findings suggest a limited role for sex in the perception of facial affect.

Adolescent↗

PubMed2004

Biosocial factors, sexual orientation and neurocognitive functioning.

It has been proposed that sexual orientation related differences in cognitive performance are either due to the actions of prenatal factors early in development or the influence of gender role learning. This study examined the performance of 240 healthy, right-handed heterosexual and homosexual males and females (N = 60 per group) on a battery of cognitive tasks comprising mental rotation, judgement of line orientation (JLO), verbal fluency, perceptual speed and object location memory. Measures were also taken of the psychological gender, birth order, sibling sex composition and the 2nd to 4th finger length ratios of the right and left hands. A series of stepwise regression analyses revealed that sex and sexual orientation were the strongest predictors of cognitive performance, with IQ also contributing considerable variance. Psychological gender (M/F scores) added a small, but significant, amount of variance to mental rotation and perceptual speed scores in addition to these main factors, but prenatal hormone related indices, such as 2nd to 4th finger ratios, birth order and sibling sex composition added no independent predictive power. These findings are discussed in relation to biosocial influences on cognitive differences between heterosexuals and homosexuals.

Adolescent↗

PubMed2004

Developmental instability is associated with neurocognitive performance in heterosexual and homosexual men, but not in women.

Little is known about the neurodevelopmental nature of human cognitive abilities. This investigation presents evidence consistent with a hypothesis that interindividual and within-sex cognitive variations are associated with vulnerabilities to environmental sources of developmental stress. A large sample of healthy heterosexual and homosexual men and women (N=240) completed a series of visuospatial and verbal tests. A composite fluctuating asymmetry (FA) measure was computed from the lengths of the finger digits. In heterosexual men, higher FA scores were associated with poorer line orientation judgment; and in homosexual men, with poorer verbal fluency and perceptual speed. No associations were found in heterosexual or homosexual women. These results suggest that developmental instability is linked to neurocognitive integrity in men, but not in women.

Adolescent↗

PubMed2004

Performance differences between adult heterosexual and homosexual men on the Digit-Symbol Substitution subtest of the WAIS-R.

Previous evidence suggests that sexual orientation influences performance on a number of cognitive functions known to be sexually dimorphic. This investigation examined the performance of 240 right-handed subjects (60 heterosexual men, 60 homosexual men, 60 heterosexual women and 60 homosexual women) on one of the most commonly used neuropsychological tests to show normative sex differences, the Digit-Symbol Substitution test of the WAIS-R. Analysis of scaled Digit-Symbol scores revealed that heterosexual women and homosexual men outperformed heterosexual men. The magnitude of these differences were modest by standard criteria. No differences were found between heterosexual and homosexual women. The findings implicate within-sex variation in one test that relies on intact executive function.

Adolescent↗

PubMed2003

Sexual orientation related differences in spatial memory.

The purpose of this study was to investigate and extend previously reported sex differences in object location memory by comparing the performance of heterosexual and homosexual males and females. Subjects were 240 healthy, right-handed heterosexual and homosexual males and females. They were instructed to study 16 common, gender-neutral objects arranged randomly in an array and subsequently tested for object recall, object recognition and spatial location memory. Females recalled significantly more objects than males, although there were no group differences in object recognition. Decomposition of significant interactions between sex and sexual orientation on spatial location memory (controlling for differences in object recall, age and IQ) revealed that heterosexual females and homosexual males scored better than heterosexual males, and no different from each other. There were no differences between homosexual and heterosexual females. The findings suggest that homosexual males and heterosexual females encode, store and retrieve positional and relational information about spatial layouts similarly, pointing to within-sex variations in the neural architecture underlying spatial memory.

Female↗

PubMed2003

EEG responses to visual erotic stimuli in men with normal and paraphilic interests.

Contingent negative variation and evoked potentials to visual erotic stimuli were recorded from 8 brain sites in a sample of 62 right-handed men aged 20-50, half of whom declared paraphilic interests and half claimed "normal" heterosexual interests. To quantify erotic preferences, a "variance quotient" (VQ) was calculated from scores on the Wilson Sex Fantasy Questionnaire using the formula VQ = Impersonal + Sadomasochistic fantasies/Intimate + Exploratory fantasies. Stimuli consisted of 57 paraphilic slides (depicting fetishistic and sadomasochistic themes), 57 heterosexual erotic slides (explicit pictures of nude women, coitus, and oral sex), and 57 neutral slides (landscapes and street scenes). The P600 response appeared to be the best indicator of erotic preferences, butthe locus of maximum arousal was different for paraphilic and heterosexual stimuli. The primary brain site for heterosexual arousal was P4 (right parietal), where there was a -.34 (p < .01) correlation between VQ and P600 (i.e., nonvariant males showed greater responses to normal erotic stimuli at this location). For paraphilic stimuli, there was a correlation of .26 (p < .05) between the VQ and P600 response at the F3 (left frontal) site (i.e., paraphilic men showed greater responses to paraphilic stimuli than normal men at this brain location). Dividing the sample into groups of 23 paraphilics and 23 heterosexual controls on the basis of their VQs showed that "normals" differentiated between stimulus types more at the P4 than paraphilics. Theoretical and clinical implications of these findings are discussed.

Adult↗

PubMed2003

Sexual orientation-related differences in prepulse inhibition of the human startle response.

Prepulse inhibition (PPI) refers to a reduction in the startle response to a strong sensory stimulus when this stimulus is preceded by a weaker stimulus--the prepulse. PPI reflects a nonlearned sensorimotor gating mechanism and also shows a robust gender difference, with women exhibiting lower PPI than men. The present study examined the eyeblink startle responses to acoustic stimuli of 59 healthy heterosexual and homosexual men and women. Homosexual women showed significantly masculinized PPI compared with heterosexual women, whereas no difference was observed in PPI between homosexual and heterosexual men. These data provide the first evidence for within-gender differences in basic sensorimotor gating mechanisms and implicate the known neural substrates of PPI in human sexual orientation.

Acoustic Stimulation↗

PubMed2003

Sexual-orientation-related differences in verbal fluency.

This study examined the performance of 60 heterosexual men, 60 gay men, 60 heterosexual women, and 60 lesbians on 3 tests of verbal fluency known to show gender differences: letter, category, and synonym fluency. Gay men and lesbians showed opposite-sex shifts in their profile of scores. For letter fluency, gay men outperformed all other groups; lesbians showed the lowest scores. For category fluency, gay men and heterosexual women jointly outperformed lesbians and heterosexual men. Finally, gay men outperformed all other groups on synonym fluency, whereas lesbians and heterosexual men performed similarly. A difference between heterosexual men and women was demonstrated on category and synonym fluency only. The findings implicate within-sex differences in the functioning of the prefrontal and temporal cortices.

Adult↗

PubMed2003

Large sexual-orientation-related differences in performance on mental rotation and judgment of line orientation tasks.

This study examined the performance of heterosexual and homosexual men and women on 2 tests of spatial processing, mental rotation (MR) and Benton Judgment of Line Orientation (JLO). The sample comprised 60 heterosexual men, 60 heterosexual women, 60 homosexual men, and 60 homosexual women. There were significant main effects of gender (men achieving higher scores overall) and Gender x Sexual Orientation interactions. Decomposing these interactions revealed large differences between the male groups in favor of heterosexual men on JLO and MR performance. There was a modest difference between the female groups on MR total correct scores in favor of homosexual women but no differences in MR percentage correct. The evidence suggests possible variations in the parietal cortex between homosexual and heterosexual persons.

Adolescent↗