Neuropsychology Flashcards
What is Cognitive Neuropsychology?
Type of neuropsychology in which people with brain damage are studies in order to learn more about cognitive functions e.g. separation of implicit & explicit memories
What are the Pros of Neuropsychological studies?
- Can show which brain areas are necessary for a particular function (neuroimaging can tell us which regions seem to be active during cognitive processes)
- Can show us what processes are unitary, and might be made up of separable sub-processes
What are the Cons of Neuropsychological studies?
- Normally looks at single case studies & individual differences in performance could be a confounding variable
- Brain may change way it functions, or change its structure, to compensate for damage (brain plasticity)
- Brain damage is rarely neat isn’t usually limited to one structure, if it is its only a portion of the structure
What is retrograde amnesia?
The inability to remember information acquired before the onset of amnesia
What is anterograde amnesia?
The inability to remember information acquired after the onset of amnesia
What happened to Henry Molaison (H.M.) resulting in anterograde amnesia?
Underwent surgery to treat his epilepsy, resulting the removal of a large bilateral portion of the medial temporal lobes, including the hippocampi
- his short-term memory was relatively unaffected, but he could not make new memories
How was Henry Molaison’s (H.M.) memory affected by his surgery to treat his epilepsy?
Explicit-Implicit Dissociation Amnesia
He suffered from anterograde amnesia
- unable to consolidate & store new information in LTM
- able to carry conversation but after several mins later he was unable to remember having had the exchange
His short-term memory was relatively unaffected
Normal attention & working-memory capacities
Implicit memory remained intact
How were explicit and implicit instructions used in studies of Explicit-Implicit Dissociation in Amnesia?
Ps did a likert rating of the study list of words
Implicit condition:
- Complete stems with first word that comes to mind
Explicit instruction:
- Complete stems with words from likert-rating task
What brain damage did L.H. (a participant in Keane et al., 1995 study of memory loss due to traumatic brain injury) suffer from?
Severe closed-head injury at age 18, which caused him to undergo a right temporal lobectomy
- Damage/removal of right inferior temporal gyrus, fusiform gyrus
- Severe damage to parietal & occipital lobes
- Hippocampus & parahippocampus gyrus largely spared
How did L.H. (a participant in Keane et al., 1995 study of memory loss due to traumatic brain injury) recognise individuals?
By the sound of their voice (could not recognise faces)
What are the Pros of using neuropsychology to study Amnesia?
- Can show which brain areas are necessary for a particular function
- neuroimaging studies = the hippocampus is active during declarative memory, but doesn’t show whether it is necessary. When looking at patient with destroyed hippocampus, can see it is necessary for memory - Can show us what processes are unitary, and might be made up of separable sub-processes
- By seeing dissociation between implicit & explicit memory
What are the Cons of using neuropsychology to study Amnesia?
- When we measure what functions have been lost, the results can only be as reliable and specific as the tests that are used
- Brain damage is rarely neat e.g. post-mortem of H.M. showed a small portion of hippocampus remained, but it had been thought to have been completely destroyed
What does a left hemisphere stroke typically disrupt?
Language function in:
- 98% right handed people
- 70% left handed people
Tachistoscope studies have shown the following stimuli to be most efficiently processed by which hemisphere?
- Language (words)
- Faces (& other visuospatial stimuli)
- Left hemisphere (so shown to right visual field)
2. Right hemisphere (so shown to left visual field)
What is the corpus callosum?
Bundle of fibres that join the two hemispheres of the brain
