Week 9 - neuropsychology Flashcards
Traditionally, neuropsychology is the study of what?
individuals with brain damage due to injury, disease/illness, or surgery in order to map structure to function.
What is cognitive neuropsychology?
a type of neuropsychology in which people with brain damage are studied in order to learn more about cognitive functions.
Recently, the definition of neuropsychology has been expanded to include what?
the biological substrates of psychological disorders.
What are the pros of neuropsychological studies?
Can show is which brain areas are necessary for a particular function.
Can show us what processes are unitary, and might be made up of separable sub-processes.
What are some cons of neuropsychological studies?
Normally look at single case studies - individual differences in performance could be a confounding factor
The brain may change the way it functions, or change its structure, to compensate for damage to particular structures (plasticity)
When only measure functions have been lost, the results = only be as reliable and specific as the tests used
Brain damage is rarely neat – most of the time damage won’t be restricted to one structure, or if it is it will be only a portion of that structure
What can amnesia be caused by?
Head injury (closed/penetrating),
Severe hypoxia (carbon monoxide poisoning / cardiac arrest)
Herpes encephalitis
Wernicke-Korsakoff Syndrome
Transient global amnesia
Transient epileptic amnesia
All of the above involve damage to either the medial temporal lobes or the basal ganglia, however other areas are also often involved.
What are the main features of amnesia?
Pronounced anterograde amnesia (inability to remember information acquired after the onset of amnesia)
Variable retrograde amnesia (inability to remember information acquired before the onset of amnesia)
Intact working memory (e.g., digit span)
Preserved general intelligence (IQ)
Skills such as driving and music are unaffected
Some residual learning capacity remains
What is Korsakoff’s Syndrome?
The result of long term alcoholism.
What are the main symptoms of Korsakoff’s Syndrome?
Anterograde and retrograde amnesia, Confabulation (The patient glibly produces plausible stories about past events rather than admit memory loss) Meagre content in conversation Lack of insight Apathy
What causes Korsakoff’s Syndrome?
thiamine (vitamin B1) deficiency, prolonged intake of excessive alcohol
Syndrome can be arrested by massive doses of vitamin B1, but cannot be reversed, and has poor prognosis.
Traumatic brain injury typically produces what?
time-dependent retrograde amnesia. The severity of the injury will determine how far back in time the memory loss stretches, and as it heals the memory will return.
What happened to Henry Molaison (Patient H.M.; 1926-2008)?
Underwent surgery resulting in the removal of a large bilateral portion of MTL, including the hippocampi (for treatment of epilepsy). As a result, his STM was relatively unchanged, but he was unable to make new memories (anterograde amnesia).
What is System Consolidation Theory (Squire & Bayley (2007)?
The hippocampus consolidates new memories, when consolidation is complete they are stored elsewhere in the brain (e.g., neocortex).
This explains why older memories tend to survive hippocampal damage – they have been transferred elsewhere for storage, whereas newer memories are more likely to be lost.
What is Reconsolidation Theory (Tronson & Taylor (2007)?
Memories will rarely consist of a single trace or neural substrate. We frequently recall memories, think about them, and discuss them
Each time a memory is used, it is reconsolidated; each use of memory is associated with a new phase of storage, resulting in many different traces for the same event
A left hemisphere stroke would likely result in what?
disrupt language function in 98% of right-handed people.
