Q. Representational knowledge can be investigated neuro-cognitively through the studies of amnesia.” Elaborate this statement. (CSE 2008, 15 marks* adjusted )
Model answer outline :
Cognitive neuroscience examines how the structure and function of the brain explain cognitive processes. Neuroscience methods like brain lesion, regional cerebral blood flow studies(eg PET scan) , evoked potential, technique, single cell recording technique etc have enabled researchers to understand WHERE information is processed and REPRESENTED in the brain.
The case study of HM having anterograde amnesia, shows that information in STM is sent to LTM due to Hippopotamus. The same brain structure however doesn’t control the development of implicit or procedural LTM as HM showed improvement in procedural memory.
The case study of KF, who had dysfunctional STM but functional LTM, however has raised question questions on hippocampus theory and pathway mechanisms.
Research on amnesic patients by Warrington and Roediger shows a concept of representation called ” Dissociation“. A dissociation occurs when a variable has large effects on one kind of test, but little, no effects or just opposite effects on another kind of test. Explicit and implicit dissociation was evident from their research studies.
Similarly, cases of prosopagnosia or inability to recognize the faces of familiar people show the role of brain structure in the memory of image.
Korsakoff syndrome involves confabulation( make up) which shows false memories about the past events. Cognitive tests reveal that they don’t do it intentionally. False memories are the fillers of the missing information. Moreover, it also shows gradient in the retrograde amnesia in which severe forgetting is of the recent events than of the remote past.
Likewise, we have postmortem data and data from evoked potential technique used on the Alzheimer’s patients, that show distorted memory representation of the past events.