Tuesday 19 November 2002


Its funny, we were giving presentations today in animal behaviour class and I noticed something; in experiments where students tested for learning ability, a negative stimulus had more of an impact on the animals than a positive one. For example, one group tested colour preference and association in lady bugs using negative stimuli (heat and ice). The lady bugs seemed to have learned to associate a colour with heat or ice and when placed in the same type of container without the stimulus, avoided the colour that the stimulus had been placed with. However in my experiment with crab spiders, I tested colour association with a positive stimulus (a food source). But the spiders didn't learn to associate colour with prey and when placed in a container lined half with the colour the prey were to be associated with and half with another colour, the spiders did not spend more time on the colour expected compared to the other colour. Why is it that negative experiences are always better remembered than positive ones? Pain and pleasure have different sensory locations inside the brain so maybe the pain centre is larger than the pleasure centre and that is why more information is retained on negative things instead of positive things. Oh well, just my theory. Well, I think its time for bed now.