Gender differences in the functional organization of the brain for working memory

Abstract

Gender differences in brain activation during working memory tasks were examined with fMRI. Seventeen right-handed subjects (nine males, eight females) were studied with four different verbal working memory tasks of varying difficulty using whole brain echo-planar fMRI. Consistent with prior studies, we observed activation of the lateral prefrontal cortices (LPFC), the parietal cortices (PC), and additionally, caudate activation in both sexes. The volume of activated brain tissue increased with increasing task difficulty. For all four tasks, the male subjects showed bilateral activation or right-sided dominance (LPFC, PC and caudate), whereas females showed activation predominantly in the left hemisphere. The task performance data demonstrated higher accuracy and slightly slower reaction times for the female subjects. Our results show a highly significant (p < 0.001) gender differences in the functional organization of the brain for working memory. These gender-specific differences in functional organization of the brain may be due to gender-differences in problem solving strategies or the neurodevelopment. Therefore, gender matching or stratification is required for studies of brain function using imaging techniques.

Low Doses of Δ-9 Tetrahydrocannabinol (THC) Have Divergent Effects on Short-Term Spatial Memory in Young, Healthy Adults

“…Recently, a consensus has emerged that gender-differences likely reflect a mixture of differences in abilities and the impact of psychosocial factors such as differential training in specific cognitive domains (Stumpf, 1995). Particularly pertinent to the current data are observations that males show an advantage in number ability, space orientation, and space visualization (Stumpf, 1995) that may reflect differences in the functional organization of anterior cortical systems responsible for working memory (Speck et al, 2002). It seems likely that the greater effects of THC on the memory scores of female compared to male participants is consistent with observations that pharmacological effects depend upon the level of baseline performance of participants under placebo, and are greatest in those whose baseline scores allow greater room for change (Kimberg and D'Esposito, 2003;Luciana et al, 1992;Miller et al, 1977).…”

Sex differences in brain activation elicited by humor

“…The prefrontal cortex (PFC) is likely to correlate with humor integration because it manages response to multiple stimuli while balancing the input of information (18). Specifically, activation of the left lateral inferior frontal gyrus (IFG), encompassing Broca's area, may modulate language comprehension and decoding of stimuli (10), whereas the middle frontal gyrus (MFG), including the dorsolateral PFC (DLPFC), has been implicated in executive functioning that may be crucial to examining, deconstructing, and understanding humorous stimuli (7,(19)(20)(21).…”

“…We also postulated that, because of the variety of studies citing greater female use of working memory and verbal function (20,29,30), females would recruit more PFC than males.…”

Individual Differences in Working Memory Performance: «overload» Effect

“…Аналогичные результаты были получены в работе Speck et al [34]. Вместе с тем, например, в исследовании Gur et al [17] значимого влияния половых различий на продуктивность РП не обнару-…”

“…Аналогичные результаты были получены в работе Speck et al [34]. Вместе с тем, например, в исследовании Gur et al [17] значимого влияния половых различий на продуктивность РП не обнару-жено, хотя зафиксировано, что женщины достоверно лучше справлялись с заданиями на вербальную эпизодическую память и на внимание.…”