Gender differences in performance on tests of cognitive abilities: Experimental design issues and empirical results

Gender Differences in Executive Functions of Patients Operated for Mild to Moderate Epidural Hematoma

Background Impairment in neurocognitive functions are commonly followed by Epidural hematoma (EDH) . This cross-sectional study was aimed to study gender differences in neurocognitive functions in mild to moderate epidural hematoma patients (43 male and 19 female patients) post-surgery using standardized assessment tools of comprehensive neurocognitive function attention, speed, working memory, fluency, set-shifting, perseveration, planning and response inhibition.

Methods Descriptive statistics, i.e., mean and standard deviation (SD) values were computed, and a t-test was applied for further exploration.

Results The analysis of results shows that on the test of working memory, female group scored better as significant differences were found on N-Back (2 Back versions) and digit span-backward. On the verbal fluency test (COWA), significant difference was found as females scored higher than the male group on total responses. However, the male group was higher in total time and error than the female group on the test of sustained attention and divided attention.

Conclusion This study shows interesting results in terms of gender differences in executive function of patients operated for mild to moderate epidural hematoma. These findings have significant clinical and implications for planning intervention. The neuropsychological rehabilitation of patients operated for mild to moderate epidural hematoma has a crucial role in enhancing their recovery and overall functioning. Inputs about gender differences in neuro psychological functioning of these patients would help in decision making regarding neuropsychological rehabilitation incorporating the gender related differences too in their intervention plan.

Spatial Ability and Academic Success of Sixth Grade Students at International Schools

Tests of verbal and mathematical reasoning ability (the Verbal Ability, Quantitative Ability and Mathematics subtests of the CTP III) and a test of spatial ability (the CTY Spatial Test Battery, Form HH) were used to predict academic success in a sample of 423 sixth graders at international schools. The reasoning measures showed high correlations with success (as measured by the grade point average (GPA)); the scores on the spatial test, too, were substantially correlated with GPA, although this correlation was somewhat lower than those of the reasoning measures. When the sample was divided into native English speakers and students with English as a second language (ESL students), native speakers were found to have an advantage on the reasoning tests, especially on the verbal one, but not on the measure of spatial ability. With small group differences on the GPA, the reasoning tests, especially the verbal test, underestimated the academic potential of the ESL students. It was concluded that the spatial test can contribute to reducing the bias against ESL students that is likely to occur when measures of verbal reasoning ability are administered to members of this population.

Forgive and Forget: Differences between Decisional and Emotional Forgiveness

To forgive and forget is a well-known idiom, which has rarely been looked at empirically. In the current experiment, we investigated differences between emotional and decisional forgiveness on forgetting. The present study provides the first empirical support that emotional forgiveness has a strong influence on subsequent incidental forgetting. Specifically, our results demonstrate that emotional forgiveness leads to substantially higher levels of forgetting in respect to offense relevant traits compared to both decisional forgiveness and no forgiveness. This provides evidence for our hypothesized effect that only individuals who have emotionally forgiven a transgression, and not those who just decided to forgive, subsequently forget offense relevant traits attributed to the transgressor.

Sex Differences in Working Memory

In two separate studies, sex differences in modal-specific elements of working memory were investigated by utilizing words and pictures as stimuli. Groups of men and women performed a free-recall task of words or pictures in which 20 items were presented concurrently and the number of correct items recalled was measured. Following stimulus presentation, half of the participants were presented a verbal-based distraction task. On the verbal working-memory task, performance of men and women was not significantly different in the no-distraction condition. However, in the distraction condition, women's recall was significantly lower than their performance in the no-distraction condition and men's performance in the distraction condition. These findings are consistent with previous research and point to sex differences in cognitive ability putatively resulting from functional neuroanatomical dissimilarities. On the visual working-memory task, women showed significantly greater recall than men. These findings are inconsistent with previous research and underscore the need for further research.

Low doses of delta-9 tetrahydrocannabinol (THC) have divergent effects on short-term spatial memory in young, healthy adults

Evidence suggests that manipulating spatial information within working memory depends upon a circuitry organized around the prefrontal cortex (PFC) and the activity of the catecholamine systems. Other evidence attests to the effects of Delta-9 tetrahydrocannabinol (THC) on short-term spatial memory function, most probably involving CB(1) receptor activity within hippocampal circuitries. At the current time, there have been no systematic studies of the effects of THC on spatial working memory in human subjects using tasks known to depend upon frontotemporal neural circuitries. We examined the effects of a single sublingual 5 mg dose of THC on a test of spatial working memory (requiring active manipulation of remembered spatial information for the management of future behavior) and a test of spatial span (requiring only the reproduction of sequences of previously presented spatial cues). In all, 19 healthy adults were administered 5 mg THC and placebo in a double-blind, placebo-controlled, within-subject, crossover design. Male participants performed more accurately than female participants. THC significantly enhanced spatial working memory performance of female participants. By contrast, male and female participants produced more intrusion errors during performance of the Spatial Span task. These results suggest that THC has relatively complex effects on spatial memory in human subjects, perhaps reflecting altered CB(1) receptor activity within frontotemporal circuits or altered activity of mesocortical dopaminergic pathways in PFC areas associated with spatial memory.

Allgemeine und domänenspezifische kognitive Leistungen

In dieser Studie wurde das Verhältnis von allgemeinen und domänenspezifischen kognitiven Leistungen bei Schülergruppen in unterschiedlichen Schultypen untersucht. Theoretische Auffassungen gehen einerseits davon aus, dass die allgemeine Intelligenz domänenspezifische Leistungen (mathematische oder fremdsprachliche) determiniert, andererseits wird die Position vertreten, dass domänenspezifische Leistungen mehr von speziellen Fähigkeiten bestimmt werden. Die Stichprobe bildeten zehn- bis elfjährige Schülerinnen und Schüler fünfter Klassen aus mathematisch bzw. sprachlich orientierten Gymnasien (Versuchsgruppe) sowie aus der Förderstufe einer Sekundarschule (Kontrollgruppe). Die beiden gymnasialen Subgruppen gleichen sich in den Intelligenztestleistungen und liegen mehr als eine Standardabweichung über den Leistungen der Kontrollgruppe. Es wurden domänenspezifische Variablen gefunden, die zwischen den beiden gymnasialen Gruppen gut diskriminieren. Faktorenanalytisch konnte ein mathematisch-räumlicher und ein fremdsprachlicher Faktor ermittelt werden.