Amnesias

Modified: 2024-07-05 10:51 AM CDST

• Amnesia is the loss of memory.
  • These figures graphically represent of anterograde and retrograde amnesia.
• Several kinds of amnesia exist.
  • Anterograde amnesia is when new memories cannot be stored.
  • People with anterograde amnesia literally live in the present at all times.
  • They have to be cared for because they could injure themselves or others.
    • For example, they could decide to turn a burner on in the kitchen and not remember that it was on.
  • People with anterograde amnesia can read the same newspaper every few minutes and not realize that they have already read it.
    • They do not remember reading it.

• Oliver Sachs, the neurologist, describes the case of Jimmy, a 50 year-old-victim of anterograde amnesia.
• When Sachs first met Jimmy at the hospital, he was greeted with a friendly, " Hi ya Doc."
  • Half an hour later when they met again, Jimmy used the same greeting.
    • Sachs asked whether they had ever met before. Jimmy said, "no. "
    • When Sachs asked how Jimmy knew that he was a doctor, Jimmy said it was because of the way Sachs was dressed.
  • Jimmy was stuck in the year 1945, it turned out.
    • He only remembered one or two events since that year. (One was the death of his brother, which says something about the relationship of emotions and encoding.)
    • Sachs first asked Jimmy how old he was, and Jimmy said he was 18.
    • Sachs then asked, "Does this look like the face of an 18-year-old?"
    • Jimmy's face changed and he stalked off.
  • An hour later he saw Sachs again and said, "Hi ya Doc."
  • Jimmy was also very good at checkers, but could not play chess.
    • Can you see why?
  • Jimmy's condition was probably caused by alcohol- related damage to specific brain areas.
    • Can you imagine what it would be like to have anterograde amnesia?
    • Can you see how much of your life depends on long term memories?
• In retrograde amnesia, subjects fail to recall items they have already encoded into long-term memory.
  • Typically, the loss is linear and runs from the present to the past. One can judge the severity of retrograde amnesia by questioning subjects. For example, if they cannot remember their names, then you know that their amnesia extends far into their pasts.
  • The old Jan and Dean song, "Dead man's curve," is about retrograde amnesia. In that song, two drivers race to dead man's curve, and the narrator says:

• The accident caused the narrator to forget everything from the time they started to swerve until he woke up.
  • The loss of memory was caused by the accident, and is a case of organic amnesia or amnesia traceable to a physical cause.
  • Drug related blackouts (e.g., caused by alcohol) may lead to short episodes of retrograde amnesia.
  • Victims do not pass out, but continue to behave. Later, they cannot recover memories of what they did while in a blackout.
• Shelly West's country music song, Jose Cuervo, contains lyrics about an alcoholic blackout:

• She cannot recall what she did the night before, later when she wakes up she finds herself in bed with a stranger and wearing his shirt.
• Psychogenic amnesia is caused by psychological trauma like surviving a natural disaster, combat, or injury.
  • For example, Sirhan Sirhan, the convicted assassin of Robert F. Kennedy, claimed he had no memory of being in the room or pulling the trigger, obviously many people disbelieve his testimony.
  • He's been denied parole many times but he still maintains he cannot remember.
  • You can think of psychogenic amnesia as a subconscious way of protecting yourself from memories of those traumatic events.