Memory Flashcards
What are the 2 main types of memory and their sub types
1-Explicit/Declarative memory : involves conscious recalling. Sub types are Episodic memories (memory of events), and Semantic memories (general knowledge)
2- Implicit/Non-declarative memory: does not involve conscious recalling. Sub types: Procedural memories : knowing how to do activities like riding a bike - and Associative learning
Episodic Memories and Semantic memories meaning
Episodic: remembering particular events, Semantic: general knowledge like knowing the capital of a city
Procedural Memories meaning
Knowing how to carry out actions automatically such as riding a bike, getting dressed, eating
What did george miller propose in 1956
Short term memory can typically hold no more than 7 plus or minus 2 pieces of information but this can be increased by chunking large pieces of info
Short term memory duration
less than 30 seconds on average, can be extended through rehearsal
Duration of long term memory
Infinite, relatively permanent storage area
Role of Hippocampus and where is it located
Binds information together to create an episodic memory. Essential for explicit/declarative memories, otherwise only conditioning learning possible!
Located in MEDIAL-TEMPORAL LOBE.
Mechanism of the hippocampus (3 steps)
- Creates new synapses
- Pre-synaptic facilitation
- Long term potentiation
Definition of AMNESIA
Partial or total loss of memory, often resulting from shock, psychological disturbance, illness or brain injury
Common types of organic cause of amensia (ie: not due to psychological reasons)
Head injury, destructive surgery, alcohol abuse (black out or korsakoff’s syndrome), Progressive dementia : alzheimer, stroke
Psychogenic causes possible for amnesia
Childhood trauma, multiple personality disorder, dissociative disorder
In long term memory, what are two types of amnesia possible
ANTEROGRADE (inability to recall new memories that happened after the trauma), and RETROGRADE (inability to recall memories prior to trauma)
Describe the medical case of H.M patient
Henry Gustav Molaison suffered from severe epilepsy from the age of 10 yo- had hippocampus, amygdala and part of temporal areas removed - ended up with SEVERE ANTEROGRADE amnesia, and some retrograde amnesia. Could not encode and store new information (from STM to LTM). Preserved short term memory and motor skills. Never recovered.
Why was H.M important, his contribution and cite a study that showed how his procedural memory was intact
Because we knew exactly what was done to his brain, what was removed, whereas brain trauma is typically non specific.
CORKIN, 1968: MIRROR TRACING TASK: he learns a task everyday but never remember consciously doing so.
Contribution: provided evidence for different STM and LTM stores, evidence for key role of temporal lobe structures especially hippocampus in consolidating memories and transferring them to LTM.
What happens if the hippocampus is damaged
Interruption of the consolidation process for recent memories but memory can return with time depending on severity of damage through reherseal for example.