ERQ Flashcards
research methods
Rogers & Kesner
HM
Rogers & Kesner
Rogers & Kesner conducted a laboratory experiment to determine the role of the neurotransmitter acetylcholine in spatial memory formation; multiple acetylcholine receptors in the hippocampus play a role in the consolidation of memory. Firstly, the researchers had mice run a simple maze to find food that was placed in one of the two corners. After having run the maze, but before memory could be consolidated, the mice were injected with one of two chemicals into their hippocampal region. The first group was injected with scopolamine, which blocks the acetylcholine receptors and thus inhibits the response. The second group was a control one, given a placebo injection of saline solution to make sure that getting an injection does not cause any change in memory. Thereafter, the two groups were placed again into the maze to see how long it would take them to find the food they had previously located. The results show that the scopolamine group took longer and made more mistakes in finding the food, whereas the control group learned faster and made fewer mistakes. All in all, the findings indicate that the neurotransmitter acetylcholine may play an important role in the consolidation of spatial memory and retrieval.
Rogers & Kesner evaluation
One of the most significant strengths of a laboratory experiment is that it has a highly standardized procedure so the study can be replicated by other researchers, and the reliability of the results can be further tested. Experiments also try to control extraneous variables and randomly allocate participants to conditions, which increases the internal validity, allowing for a cause-and-effect relationship to be established. On the other hand, they suffer from low ecological validity due to the highly controlled environments, meaning that the results may not reflect behavior under normal conditions. It is also not always clear to what extent the results of animal research may apply to human beings such as from rats to humans in the Rogers & Kesner study.
Case study
Another research method in the biological approach is a case study. Case studies are comprehensive investigations of one individual with a particular brain abnormality or damage; case studies provide situations that cannot be ethically reproduced by researchers in a laboratory under controlled conditions. They are also often carried out longitudinally to observe short-term and long-term effects, where the same variables are investigated in repeated and different types of observations over long periods of time. An independent variable is not manipulated in this type of research and hence, no causal relationship can be established. In addition, psychologists study brain-damaged patients by using triangulation - for example, more than one method, researcher, and different sources of data.
evaluation of HM
One of the strengths of case studies is that they collect rich data. Case studies collect data over a long period of time, accounting for both short-term and long-term effects on the patient’s behavior; they also use a more holistic approach as opposed to experiments by looking at a range of behaviors, rather than measuring a single dependent variable. In addition, the use of method triangulation increases the validity of the results. Nevertheless, generalizability is one of the most critical limitations of this type of research method; case studies often study brain abnormality or damage that is unique to an individual and for that reason, the observed results cannot be generalized to the behavior of all human beings. In addition, a causal relationship cannot be established as an independent variable is not manipulated in this type of research. Lastly, it might also be difficult for the researcher to acquire and verify information about the patient before his/her accident, which may otherwise be of some use when drawing conclusions.
