Cognitive Processes: Memory Types and Their Implications Oct 27th

Definition: General knowledge about the world, facts, concepts, and meanings.
- Example: If someone asks "Was she there?" the answer relates to semantic memory.

Evidence suggests episodic and semantic memory are distinct types regulated by different brain regions.
- Episodic Memory Activation:
- Associated with frontal lobe activation when recalling specific events.
- Semantic Memory Activation:
- More posterior cerebral cortex involvement; generalized knowledge retrieval.

Definition: Loss of long-term memory.
- Distinct types of amnesia affect various types of memory, generally leaving procedural and some semantic memory intact.
- Most affected: Episodic memory (difficulty recalling past events).
- Patients may remember facts or skills (semantic/procedural memories).
- It implies injury to specific brain regions related to episodic memory while sparing others used for semantic memory.

Amnesia studies provide insight into the separateness of memory types:
- Loss of episodic memory indicates distinct neurological underpinnings from semantic memory, which often remains intact.
- Brain injury patterns reveal associations with memory type deficits.

Overview: Memory models using nodes and connections to represent memory structure.
- Nodes: Circles representing concepts or pieces of information (neurons).
- Connections: Lines representing the relationships and pathways between nodes, excitable or inhibitory.
- Function: Helps explain memory processes, particularly in long-term memory.

To retrieve a memory, the node must be activated above a threshold.
- Activation represents the strength of connection; stronger connections require less activation to retrieve memories.
- Example: Remembering a weekend event by activating associated nodes.

Studying strengthens connections between nodes.
- Without study, connections remain weak, leading to retrieval difficulties (e.g., tip-of-the-tongue phenomenon).

Explicit Memory (Conscious):
- Awareness of facts or events (recall/recognition).
- Types: Free recall (no cues) and cued recall (with cues).
Implicit Memory (Unconscious):
- Memory reflected in behavior, not consciously recognized.
- Studied through tasks like repetition priming.

Explicit Memory Testing:
- Recall tasks (essay) vs. recognition tasks (multiple choice).
- Higher success rate for recognition due to familiarity cues.
Implicit Memory Testing:
- Repetition priming through tasks such as word completion.
- Example: Activating a memory node through partial information exposure.

Forgetting is often perceived as loss of information but may also involve lack of encoding during initial exposure.
- Connection to attention: If attention wanes, retention suffers.
Forgetting Curve:
- Explicit memory may diminish quickly without reinforcement, while implicit memory tends to stabilize and retain longer over time.
Factors Affecting Memory:
- Alcohol impacts memory formation and recall due to its effect on the hippocampus and attention levels during coding.

Example of encoding problems illustrated through a penny’s design.
- Participants asked to recall details about a penny often perform poorly due to lack of attention during initial exposure, demonstrating the importance of encoding.
Memory accuracy can vary widely based on attention and prior knowledge during initial experience with information.