NEUR200 Memory

Working memory (WM): Another term

Short term memory.

2 types of WM

Spatial and object memory.

Dorsal parietal and ventral temporal visual pathways: Where do they go?

Go to 2 different areas of prefrontal cortical areas.

What memory does dorsal support?

Action.

What memory does ventral support?

Perception

3 processes for STM AND LTM

Encoding, consolidation, retrieval

Encoding (from what to what)

From sensory system into STM.

Where does visual sensory input go during encoding?

Right PFC and right parahippocampal cortex.

Where do words go during encoding?

Left PFC and left parahippocampal cortex.

Consolidation (memory type, and brain location)

LTM ; medial temporal lobe

What type of brain area is used for consolidation?

Cortex layer 1.

Description of the cortical layer 1.

Outermost layer of the cortex. Has a few neuronal bodies but many synapses.

Engram

What pathway. (visual cortex for visual objects, auditory cortex for auditory objects).

What does retrieval require? Where?

Attention from frontal areas

What does LTM retrieval do? Diagnosis assoc.?

Helps memory become plastic and updatable. PTSD.

LTM types

Explicit and implicit

Explicit memory and types

Conscious. Semantic and episodic memory.

Episodic memory

Memory about one’s life experiences.

Semantic memory

Non-autobiographical, worldly knowledge.

Semantic memory examples

Friends, family, school knowledge.

Which brain area are neural substrates associated with? Mainly?

Temporal lobes. Hippocampus and rhinal cortex.

Neural substrate stream

Ventral

Neural substrate neurotransmitters

Acetylcholine, serotonin, and norepinephrine

LTM and hippocampus

Usually for explicit memory, mainly episodic

Spatial memory study

Morris water maze.

Spatial memory and hippocampus relation

HIPP acts as a spatial map.

Cells of spatial memory

place cells, grid cells.

Where are grid cells located?

The enorhinal cortex.

London cab drivers

HIPP is more active when they are asked spatial questions

Contextual memory

HIPP takes representation from various locations and reconstruct the context.

Anterograde amnesia

Memory disruption after the onset of disorder.

Retrograde amnesia

Memory disruption for events that occured before the onset of disorder.

Time-dependent retrograde amnesia

Severity of the amnesia dictates how much prior time the person will forget.

Two types of LT implicit memory

Fear conditioning, procedural learning

Fear conditioning

Amygdala. Damaged amygdala may disrupt emotional memory, but does little to nothing with explicit or implicit memory.

Who will suffer a negative effect with procedural learning?

Parkinsons’ patients.

What brain structure is responsible for procedural learning?

Basal ganglia

Basal ganglia

Stratium, globus pallidus, and substantia nigra.

Basal ganglia learning speed and flexibility

Gradual learning and less flexible.

What type of memory is associated with the BG?

Procedural memory

What brain area is used initally prior to using the BG?

The frontal cortex.

BG learning type

Reinforcement-based. (trial and error)

PFC and flexibility

More flexible and can switch responses.

Two glutamate receptors

AMPA and NMDA

Blocks NMDA receptors

Mg+ ions

When do NMDA receptors reopen?

After depolarization

Ca and Na with NMDA receptors

Enter and cause CREB release

CREB

Protein which can alter gene expression

Where does CREB enter

Nucleus

BDNF abbv.

Brain Derived Neurotrophic Factor

Repeated activation

Cause APs to back propagate and release BDNF

What activity can BDNF increase?

NMDA

What part was fully removed from HM

HIPP

Why did they remove part of HM’s brain?

Epilepsy

What part was partially removed from HM?

Amygdala

What type of amnesia did HM suffer.

Both anterograde and retrograde

How was HM’s WM?

Intact but only with attention

What M was better in HM?

Implicit

What was impaired with HM?

Episodic memory

What trouble do those with amnesia go through?

Imagining/planning the future

Was procedural memory intact with HM?

Intact.