Psy 2031 Lab Report

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the ten trials.

Participants calculated their 2D:4D ratio by measuring the length of their index finger (2D) and their ring finger (4D) from the bottom crease of the finger to the end of the finger in millimetres. Once the distances had been measured the ratio was calculated by dividing the length of the index finger by the length of the index finger

(i.e. 2D / 4D).

Once the online task and the 2D:4D ratio had been measured, participants were asked to enter their data into an online questionnaire. The questionnaire required participants to enter their age, gender, task accuracy, task reaction time and 2D:4D ratios.

Results

In order to determine if there was a gender difference in the 2D:4D ratio and the performance on working memory tasks, and also if there was a relationship between the variables, independent-samples t-tests and a Pearson’s correlation was used. SPSS Statistics 20 was used to process the data.

On average, males (M = 81.85, S = 16.40) had a higher working memory accuracy than females (M = 77.45, S = 18.12), with a mean difference of 4.40%. Males had a slower working memory reaction time (M = 968.6, S = 443.5) in comparison to females (M = 967.3, S = 414.3), with an average mean difference of 1.3ms. Females had a larger 2D:4D ratio (M= 0.981, S = 0.047) than males (M = 0.964, S = 0.055), with a mean difference of 0.02.

Females were found to have larger 2D:4D ratios than males as this difference was found to be significant, t(495) = 3.29, p < 0.001, one-tailed. 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.

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 larger in females than in males. The hypothesis that working memory would differ significantly across gender was not fully supported. This is because working memory in this study was measured by accuracy and reaction time. In this case, there was a significant difference in the accuracy between genders, while on the other hand there was no significant difference in reaction time between genders. Our third hypothesis predicted that there would be a relationship between 2D:4D ratio for each gender and their performance on working memory tasks. Again, this hypothesis 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.

The 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 only possible to conclude that males had greater accuracy than females when completing the spatial working memory task. In conjunction, females had a higher 2D:4D ratio than men, meaning that they had less sex hormone activity and less development of the pre-frontal cortex, the area of the brain that plays a key role in working memory tasks. This is in line with the work done by Kalmady et al. (2013) and Duff and Hampson (2001). However, because there was no relationship found between that the 2D:4D ratio and working memory accuracy, it is risky to make solid conclusion on the gender differences associated with working memory accuracy in this study.

Future direction in this field may involve finding a way to increase the performance in spatial 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 spatial working memories. Such methods may give scientists insight into developing treatments and therapies for those with learning difficulties or who have abnormal brain dysfunction.

There are several limitations in this study. Firstly, this study relied on the use of 2D:4D ratio to indirectly measure hormone levels, adds confounding variables and interpersonal differences into the equation as the 2D:4D ratios are only an estimate of sex hormone activity. This could be altered in future studies by using method that allowed for the direct measurement of sex hormones. 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, meaning that greater performance on this test doesn’t necessarily correlate with greater working memory performance.

In conclusion, study aimed to investigate the gender differences in working memory, and if so, the nature of the differences. 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, as indicated by higher accuracy for males. 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. Further research in this area could implement methods that allow sex hormone levels could be measured directly and therefore establish a cause and effect relationship between working memory performance and the 2D:4D ratio.

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References

Baddeley, A. (2010). Working memory. Current Biology, 20(4), R136-R140. http://dx.doi.org/10.1016/j.cub.2009.12.014

Chipman, K. & Kimura, D. (1998). An investigation