IB Psychology HL

Aim: To investigate if schema processing influences both encoding and retrieval Procedure: The participants were given one schema at the encoding stage and one schema at the retrieval stage, to see if they were influenced by the last schema when they had to recall the information. The participants heard a story that was based on 72 points. Half of the participants were asked to read the story for the point of view of a house-buyer and the other half from the point of view of a burglar. After a break, half of the participants were given a different schema, so the burglars switched to the buyers and vice versa. The other half were tested on their original schema again. Results: The researchers found that the group of participants in the changed schema group were able to recall 7 percent more points on the second test than on the first one. Recall of points that were directly linked to the new schema increased by 10 per cent, whereas recall of points that were important to the pr...

Bouchard et al. (1990) Aim:  To investigate the relative influence of environment and genetic factors on human characteristics and behaviours, including intelligence. Method: A cross-cultural correlational study of more than 100 pairs of reared-apart twins and siblings whose data was compared with twins and siblings reared together. The participants comprised identical (monozygotic/MZ) twins and non-identical (dizygotic/DZ) twins, with an average age of 41 years. MZ twins are often used in genetic research because they have identical or almost identical genes. Each participant underwent over 50 hours of psychological testing and interviews. In twin research, the correlation found between each twin and therefore presumable between genetic inheritance and a particular behaviour is called the concordance rate. Results: The concordance rates for IQ were: MZ twins reared together: 86% (0.86) MZ twins reared apart: 76% (0.76) DZ twins reared together: 55% (0.55) Biologi...

Martinez and Kesner (1991) Aim: To determine the role of the neurotransmitter acetylcholine on memory Procedure: Rats were trained to go through a maze and find the end, where food was located. When the rats learned how to get through the maze, he divided them into three groups. The first group was injected with scopolamine, which blocks the acetylcholine receptor sites. The second group was injected with physostigmine. Physostigmine blocks the production of cholinesterase which does the “clean-up” of acetylcholine from the synapse and returns the neuron to its “resting state”. The third group was not injected because they were the control group. Results: The results showed that the group that had been injected with scopolamine were slower and made more errors than the two other groups. The physostigmine group was faster than both groups and also made less errors when running through the maze. Conclusion: The researchers could from the results conclude that the neurotr...