---amnesia--- Flashcards
what is amnesia
severe impairment to LTM
caused by brain damage
HM
- Became amnesic in 1953 following a bilateral removal in the hippocampal zone (an (ill) attempt to cure his epilepsy).
- Can remember childhood events (Scoville & Milner, 1957).
- Memory generally poor for events after the operation.
clive wearing
- British musician and conductor.
- Acute and long-lasting case of anterograde and retrograde amnesia, meaning that he lacks both the ability to form new memories and to recall some aspects of his past memories.
- Herpes virus attacked CNS damaging his hippocampus.
- “Wakes up” every 20s.
- Has no knowledge of ever learning music (but can play the piano still).
korsakoff syndrome
- Alcohol related problem in metabolizing the vitamin thiamine, which leads to brain damage in areas of the hippocampus and diencephalon, resulting in loss of episodic memory.
- But (Cermak, 1976) – the amnesia from Korsakoffs is “less pure” as there is also subtle damage to other areas including frontal lobes.
- Gradual onset and more widespread damage makes it harder to interpret findings.
problems with using korsakoff’s syndrome to understand amnesia
- Problems with using patients with Korsakoff’s syndrome to understand amnesia.
- Gradual onset.
- Widespread brain damage.
- Inconsistent in which areas of the brain are affected.
- Brain plasticity.
retrograde amnesia
- Inability to recall information/events from before the critical incident.
- Particularly affects episodic memories compared with semantic memories (Spiers et al., 2001).
- Usually associated with damage to cortical and neocortical structures.
anterograde amnesia
- Problem with consolidation of memories (Isaac & Mayes, 1999).
- Could be caused by damage to subcortical areas.
corticol areas of the brain
are where many of our higher-level functions take place, such as language processing and decision making.
sub-corticol areas of the brain
the areas below the cortical areas of the brain, are involved with more primitive functions (i.e., emotion processing in the amygdala)
- Normal intelligence.
- Some Long term remaining memory abilities.
- Good STM performance.
Focal retrograde amnesia.
• Retrograde amnesia in the absence of Anterograde amnesia is called Focal retrograde amnesia.
Retrograde Amnesia: How do we examine recall accuracy? Patient E.D.
examined 5 years after diagnosis of retrograde amnesia.
• No anterograde amnesia.
• Examined recollection of famous events, people and cars.
• Selective deficit for public figures/events in the past 20-30 years.
• But fine on famous cars – an interest of theirs prior to diagnosis.
patient P.Z.
retrograde amnesia
- Experimental Psychologist, completed memoirs before contracting Korsakoff.
- Memoirs enabled estimation of events and of how long he had known people. The earlier the information had occurred the better recall he had from it.
- Temporally graded loss of knowledge – could remember earlier colleagues more than recent(ish) colleagues.
ribots law
Retrograde amnesia
states that recent memories are more likely to be lost than the more remote memories. -This is the typical finding for retrograde amnesia.
Memories further back in time are lost to a lesser degree