Many psychology examiners actually prefer you writing in dotpoints. <source, I did it in both my psychology exams and attained a score of 50. Also, my teacher was one of the senior people on the Psychology board, and a VCE Examiner, and was quite close with the Chief Examiner who often discussed with his exam techniques>
As I revealed in my Summer Headstart Psychology Lecture, the reasoning behind this is that, like all other subjects, psychology exam papers are marked very, very quickly by VCE Examiners. As a result, they'd much rather look through and give out marks to say 3-4 dotpoints for a 3 mark question, rather than a whole huge chunk of a paragraph, and trying to find and award marks for bits and pieces.
Writing in dotpoints for Short Answer questions is strongly advised, and also enables you to keep a guide of what sort of information/definition you're missing in your answer
