Gender Differences in Working Memory Performance as a Function of Sex Hormone Levels

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The difference observed in working memory accuracy between males and females was found to be significant, t(196.647) = -2.440, p = 0.16, two-tailed, with males performing better than females. On the other hand, there was no significant difference between males and females for working memory reaction time, t(495) = -0.029, p = .977, two-tailed. Females were found to have larger 2D:4D ratios than males as this difference was found to be significant, t(495) = 3.29, p one-tailed.

Finally, Analysis using Pearson’s correlation indicated that there was no relationship between the working memory accuracy and working memory reaction time, r(??)=.034, p = .455, two-tailed. There was also no significant relationship found between 2D:4D ratio and working memory accuracy, r(??)= .034, p = .456, two-tailed but there was a significant negative relationship between 2D:4D ratio and working memory reaction time, r(??)= -.09, p = .046, two-tailed.

Discussion

Not all of our hypotheses were completely supported by the results in the experiment. The results supported the hypothesis that the 2D:4D ratio was higher in females than in males. The hypothesis that working memory you differ significantly across gender was only partially supported. This is because working memory in this study was measured by accuracy and reaction time. That is, there was a significant difference in the accuracy between males and females while on the other had there was no significant difference in reaction time between males and females. Our third hypothesis predicted that there would be a relationship between 2D:4D ratio for each gender and their performance on working memory tasks. This hypotheses, however, was not fully supported by the results as no significant relationship was observed between 2D:4D ratio and accuracy whilst, on the other hand, there was a significant relationship between 2D:4D and reaction times.

This working memory task used in this study tested two components, the reaction time and the accuracy. Whilst there was no significant difference in the reaction times between genders, there was a significant difference in the accuracy. Therefore it is possible to conclude that males had better accuracy than females at the working memory performance task. In conjunction, females had a higher 2D:4D ratio than men, meaning that they had less sex hormone activity and thus in line with the work done by [insert source], less development of the pre-frontal cortex, the area of the brain that plays a key role in working memory tasks.

The sex difference in working memory could be explained by the fact males have a smaller 2D:4D ratio, which indicates more development of the pre-frontal cortex due to the increased levels of sex hormones [duff 2001]. These results are also in line with research compiled by….COMPLETE

Future direction in this field may involve finding a way to increase the performance of females in working memory performance tasks. This could be don’t by finding a way improve growth and development of the prefrontal cortex and other areas of the brain important for working memories. These methods may give insight of ways scientists could develop treatments of those with learning difficulties or who have abnormal brain dysfunction.

There are several limitations in this study. Firstly, we relied on the use of 2D:4D ratio to indirectly measure hormone levels, such methods increase more error into the equation as the 2D:4D ratios are only an estimate of sex hormone activity, which means confounding variables and individual differences are likely to play a larger role in the results. Secondly, it is hard to prove which form of memory was actually being measured; the assumption was that increased accuracy and faster reaction times whist completing the online task where indicative of better working memory performance. However, is possible that this test wasn’t measuring only working memory but other forms of memory such as verbal memory, for example, meaning that greater performance on this test doesn’t necessarily mean greater working memory performance. Finally…..INCLUDE 3RD LIMITATION

In conclusion, the purpose of this study was to investigate where there are gender differences in working memory, and if so, the nature of that difference. The results attained supported the hypothesis that the 2D:4D ratio was higher in females compared to males, and the hypothesis that working memory performance differed across gender. The final hypotheses that there is relationship between 2D:4D ratio for each gender and their performance on working memory tasks, however, was not supported. These results have provided insight regarding future application of this study and how this knowledge may be used to increase the growth and development of brain regions key to working memory performance. Ultimately, this study relied on correlations and thus no cause-effect relationship could be established. Father research in this area could implement methods so that sex hormone levels could be measured directly and therefore establish a cause and effect relationship between working memory performance and the 2D:4D ratio.

References

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Hönekopp, J., Bartholdt, L., Beier, L., & Liebert, A. (2007). Second to fourth digit length ratio (2D:4D) and adult sex hormone levels: New data and a meta-analytic review. Psychoneuroendocrinology,32(4), 313-321. http://dx.doi.org/10.1016/j.psyneuen.2007.01.007

Kalmady, S., Agarwal, S., Shivakumar, V., Jose, D., Venkatasubramanian, G., & Reddy, Y. (2013). Revisiting Geschwind's hypothesis on brain lateralisation: A functional MRI study of digit ratio (2D:4D) and sex interaction effects on spatial working memory. Laterality: Asymmetries Of Body, Brain And Cognition, 18(5), 625-640. http://dx.doi.org/10.1080/1357650x.2012.744414

Malas,