Memory

Patient H.M. had what brain region removed?

Medial temporal lobes

What major deficit did patient H.M. exhibit?

Inability to form new declarative (fact/event) memories

What type of memory was preserved in patient H.M.?

Procedural memory

What does patient H.M. demonstrate about memory systems?

Declarative and procedural memory are separate systems

Define short-term memory

Temporary storage of information for 30–60 seconds without manipulation

Define working memory

Short-term storage with active manipulation of information for goal-directed tasks

What is required for both short-term and working memory?

Attention

What brain regions are involved in working memory?

Lateral prefrontal cortex and posterior parietal cortex

What is declarative memory?

Conscious/explicit memory of facts and events

What are the two types of declarative memory?

Episodic and semantic

Define episodic memory

Memory of personal experiences/events

Define semantic memory

Memory of facts and general knowledge

What is encoding?

Processing information from working memory into long-term memory

What enhances encoding?

Attention

What brain region is primarily responsible for encoding?

Medial temporal lobe

What is consolidation?

Stabilization of memories for long-term storage

What are the two types of consolidation?

Synaptic and systems consolidation

Define synaptic consolidation

Short-term stabilization (~6 hours) involving early LTP

What brain structure is key for synaptic consolidation?

Hippocampus

What enhances synaptic consolidation?

Sleep and rest

Define systems consolidation

Long-term reorganization of memory over days to weeks

Where are long-term memories stored after systems consolidation?

Distributed across the cortex

What type of LTP is involved in systems consolidation?

Late LTP

What is retrieval?

Recall of stored memories

What brain regions are involved in retrieval?

Medial temporal lobe and prefrontal cortex

What cerebellar structure is involved in emotional memory retrieval?

Vermis

What happens if memories are not periodically retrieved?

They weaken/are forgotten

What are engrams?

Physical changes in neural circuits representing memories

What cellular changes occur in memory formation?

Synapse formation

What is LTP?

Long-term potentiation (strengthening of synapses)

What is LTD?

Long-term depression (weakening of synapses)

What role does the amygdala play in memory?

Enhances encoding of emotionally significant memories

What neurotransmitters/hormones are involved in amygdala-mediated memory?

Norepinephrine

What type of memories is the amygdala especially involved in?

Fear

What condition is linked to amygdala dysfunction?

PTSD

What is procedural memory?

Implicit/unconscious memory for skills and habits

What are the stages of procedural memory?

Cognitive

Define the cognitive stage of motor learning

High attention and conscious effort

Define the associative stage

Refinement with fewer errors

Define the autonomous stage

Automatic performance with minimal attention

What brain areas are involved in procedural memory?

Motor cortex

Is the hippocampus important for procedural memory?

No

Can patients with dementia learn new motor skills?

Yes

What is retrograde amnesia?

Loss of memories before an event

What is anterograde amnesia?

Inability to form new memories after an event

Why could H.M. remember old memories?

Older memories were already consolidated in cortex

Why could H.M. hold short-term information?

Working memory circuits were intact

Why could H.M. learn new skills?

Procedural memory does not rely on medial temporal lobe

What is the time frame for synaptic consolidation?

~6 hours

What is the time frame for systems consolidation?

Days to weeks

What is required for encoding to occur?

Attention

What type of memory is “muscle memory”?

Procedural memory

What type of memory is impaired in amnesia?

Declarative memory

What is the role of sleep in memory?

Enhances consolidation

What happens to unused synapses?

They weaken (LTD)

A patient can learn new motor skills but cannot recall practicing them. What type of memory is intact?

Procedural memory

A patient cannot form new memories after a brain injury. What type of amnesia is this?

Anterograde amnesia

A patient recalls childhood events but not recent ones after surgery. What explains this?

Older memories are already consolidated in cortex

Which memory type is most affected by medial temporal lobe damage?

Declarative memory

A patient is asked to repeat a phone number immediately after hearing it. What memory system is being tested?

Short-term memory

A patient mentally calculates a tip at a restaurant. What memory system is primarily used?

Working memory

Why is attention critical for memory formation?

It is required for encoding into long-term memory

A patient studies better when emotionally engaged. Which brain structure enhances this?

Amygdala

Why does sleep improve memory retention?

It enhances synaptic consolidation

A patient practices a skill repeatedly over weeks. What process is occurring?

Systems consolidation

What is the key difference between synaptic and systems consolidation?

Time scale and location of storage

A patient improves a motor task with less effort over time. What stage are they entering?

Autonomous stage

A beginner learning a new motor task requires high attention. What stage is this?

Cognitive stage

A patient refines movement with fewer errors but still requires focus. What stage is this?

Associative stage

Which brain structure is MOST critical during early memory consolidation?

Hippocampus

A patient cannot recall emotional events well. Which structure is likely damaged?

Amygdala

What happens to memories that are not retrieved over time?

They weaken and may be forgotten

A patient links new information to prior knowledge. What process is being enhanced?

Encoding

A patient demonstrates improved recall after repetition. Why?

Repetition strengthens encoding and consolidation

Which type of memory is consciously accessible?

Declarative memory

Which type of memory is unconscious and skill-based?

Procedural memory

A patient recalls what they ate yesterday. What type of memory is this?

Episodic memory

A patient recalls that Paris is the capital of France. What type of memory is this?

Semantic memory

Why can patients with hippocampal damage still learn skills?

Procedural memory uses different brain systems

A patient has difficulty retrieving memories despite intact storage. Which region may be involved?

Prefrontal cortex

What is the role of the vermis in memory?

Retrieval of emotional memories

A patient experiences strong memory recall during stress. Why?

Amygdala increases arousal and encoding

Which neurotransmitters increase during emotional memory formation?

Norepinephrine and epinephrine

Which hormone contributes to memory encoding during stress?

Cortisol

What cellular mechanism strengthens synapses during learning?

Long-term potentiation (LTP)

What cellular mechanism weakens unused synapses?

Long-term depression (LTD)

What is the purpose of weakening unused synapses?

Improves efficiency and pruning of neural networks

Why does working memory involve the prefrontal cortex?

It manages manipulation of goal-directed information

Why is the parietal cortex involved in working memory?

It supports attention and spatial processing

A patient quickly forgets information after distraction. Which memory system failed?

Working memory

What type of memory is primarily tested in immediate recall tasks?

Short-term memory

Why is procedural memory important in rehab?

It allows relearning of motor skills despite cognitive deficits

A stroke patient improves gait with repetition but cannot explain how. Why?

Procedural learning is intact

A patient has intact memory for facts but poor skill learning. Which system may be impaired?

Procedural memory system

A patient has impaired semantic memory but intact episodic recall. What does this suggest?

Different declarative subtypes can be selectively affected

What distinguishes episodic from semantic memory?

Personal experience vs general knowledge

Why does linking new information to existing knowledge improve learning?

Enhances encoding pathways

A patient studies without focus and retains little. What is the main issue?

Lack of attention during encoding

Which process occurs over hours and depends on hippocampus?

Synaptic consolidation

Which process redistributes memory across cortex?

Systems consolidation