In Statistics: in my research, im comparing the performance of introverted and extroverted students on...?

Technically a t-test is only valid if the underlying distribution of the scores is Normal. As your sample size gets really big, a mean value asymptotically is normally distributed, so a t-test is the most commonly used test for this sort of thing. Technically, you should test your samples for normality first, but I'm not sure how reasonable that is in this case.