High-Yield Physiological Psych

Lecture 5, 6, and 7

What are the three distinct memory stores?

Sensory → STM (working) → LTM

What helps sensory memory progress to the next stage?

Attention

What helps working/short-term memory progress to long-term memory?

Consolidation thru repetition

What is the relationship between long-term memory and short-term memory?

Retrieval: long term memories can be reaccessed into STM

What are the two broad divisions of LTM?

Explicit (declarative) and implicit (non-declarative)

What are the two types of declarative (explicit) memory?

Semantic (facts) and episodic (personal experiences)

List types of nondeclarative (implicit) memory.

Procedural memory, priming, classical conditioning

True or false: LTM is unitary

False, it has partially overlapping and partially distinct neurological networks

Who was patient H.M., and what surgery did he undergo?

He had epilepsy, resolved through surgery removing medial temporal lobes

What was H.M.’s main memory deficit?

Anterograde amnesia, cannot consolidate new LTMs

Define anterograde amnesia.

Inability to form new long-term memories

Define retrograde amnesia.

Inability to remember events prior to the brain damage

What happened to H.M.’s short-term memory?

Relatively intact

What did mirror-drawing performance show in H.M.?

Procedural (implicit) memory intact, without remembering doing it prior

What did incomplete-pictures tasks show in H.M.?

Priming (implicit) memory intact, does not remember prior exposure (explicit memory)

What key “dissociation” did H.M. demonstrate?

Explicit (loss) vs implicit (preserved)

What did H.M. teach us about the medial temporal lobes?

They play a key role in memory (especially forming new long-term memories)

What did H.M. teach us about STM vs LTM?

They are distinct systems

What causes Korsakoff’s syndrome?

Deficiency in B1 vitamin (poor diet/nutrition, alcoholism)

How is Korsakoff’s syndrome treated?

Vitamin B1

What is confabulation (as seen in Korsakoff’s)?

Amnesia where you remember past events but in the wrong order

What brain region is typically damaged in Korsakoff’s syndrome?

Medial diencephalon

How does early Korsakoff’s amnesia compare to medial temporal lobe amnesia?

Similar symptoms (as H.M., anterograde amnesia)

What is the general progression pattern of Alzheimer’s disease in the brain?

Will cover the entire cortex within 20+ years (spread from the hippocampus to language areas first)

What is global cerebral ischemia?

Blood flow is restricted from the brain

Which hippocampal region is most vulnerable in global cerebral ischemia?

CA1, most vulnerable = largest exit tract

What type of memory problem can global cerebral ischemia produce?

Anterograde amnesia (similar to H.M.)

Which patient demonstrated anterograde amnesia after CA1 damage from global cerebral ischemia?

R.B.

What types of amnesia can concussions cause?

Retrograde and anterograde amnesia

What do concussion-related amnesia patterns suggest?

Temporary failure to consolidate memories

State Hebb’s theory of memory consolidation.

“Cells that wire together, fire together”

According to Hebb, how are short-term memories stored?

Continuous electrical stimulation (loop) → reverberating neural activity

According to Hebb, how is long-term memory (learning) stored?

Strengthening connections between two synapses = synaptic changes → firing together

What did ECS (electroconvulsive shock) studies with rats demonstrate about consolidation?

Memory consolidation takes time

In ECS studies, what was special about information consolidated within about 3 hours?

It was resistant to disruption (had already been consolidated)

What did long gradients of retrograde amnesia from ECS therapy patient suggest?

Consolidation can continue for up to years

What is reconsolidation theory?

Memories can be retrieved from LTM → STM and be “edited” and reconsolidated that way

What is one implication of reconsolidation theory?

Treating PTSD

True or false: all medial temporal lobe structures have the same role in memory?

False - they play different roles

What is the rhinal cortex important for?

Object recognition

What is the hippocampus important for?

Spatial memory

What are place cells?

Hippocampal cells that fire when entering a specific, familiar environment

When do place cells develop their location-specific firing patterns?

After becoming familiar with an environment

Where are memories stored in the brain?

Diffusely across the brain structures involved in their initial consolidation

What is the hippocampus especially important for regarding memory storage?

Initial consolidation (before its distributed)

What does Hebbian learning say about synapses?

Co-occurrence of pre- and postsynaptic firing strengthens synapses (repeated firing together)

What is long-term potentiation (LTP)?

High-frequency stimulation strengthens a connection → neurons become more responsive to each other over time

What does LTP demonstrate?

Synaptic plasticity (learning-related strengthening of synapses)

In LTP, what happens to EPSPs after high-frequency stimulation?

EPSP responses increase, postsynaptic neuron becomes more likely to respond

Why are NMDA receptors crucial for LTP and learning?

Allow calcium entry when neurons connect → strengthens the synapse

What happens if NMDA receptors are blocked (as seen in rats task learning)?

LTP cannot occur + prevents task learning

Define a brain tumor.

Mass of cells growing independently from the rest of the body

What is a benign brain tumor?

Non-cancerous, does not invade surrounding tissue

What percentage of brain tumors are meningiomas (example of benign)

20%

What is a malignant brain tumor?

Cancerous, aggressive, invasive tumors

What is a metastatic tumor?

Example of malignant, cancerous tumor that is created somewhere else and travels to the brain

What are cerebrovascular disorders?

Blood vessel-related conditions affecting the brain

What is a stroke?

Interruption of blood flow to the brain

What is cerebral hemorrhage?

Bleeding due to bursting blood vessel

Differentiate subarachnoid vs intracerebral hemorrhage.

Subarachnoid (surface), intracerebral (deep)

What is cerebral ischemia?

Block of blood flow to the brain tissue

What is atherosclerosis?

Thickening and becoming less flexible of the arteries

True or false: damage due to cerebral ischemia is immediate.

False

What excitotoxic cascade contributes to ischemic damage?

Lots of glutamate releases → overactivates NDMA receptors → release of Na+ and Ca+ → neuron death

What is the treatment tPA and when must it be given?

Within 3 hours of stroke symptoms, tPA = tissue plasminogen activator (clot buster)

What is a TIA?

Transient ischemic attack (“mini-stroke”)

What are closed-head injuries?

Brain injuries without penetrating wounds (brain colliding with skull)

What are cerebral contusions?

Bruising of the brain, causes damage to the cerebral circulatory system

What is a coup-contrecoup injury?

Injury at impact site, and bounces and injures the opposite side of the impact site

What is a concussion?

Blow/acceleration forces causing the brain to move rapidly inside the skull

What is punch drunk syndrome/CTE?

Repeated head trauma, such as concussions/blows over time (chronic traumatic encephalopathy)

What are cerebral abscesses and how are they treated?

Pockets of pus → antibiotics like penicillin

What does a viral infection affect in the nervous system context?

Neural tissue

Define meningitis.

Inflammation of the meninges

Compare viral meningitis vs bacterial meningitis.

Bacterial is much more severe/deadly

Define encephalitis.

Inflammation of the brain tissue.

What are neurotoxins?

Toxins substances that damage nerve cells (neurons)

How can neurotoxins enter the body?

Inhaled (lungs), ingested (GI tract), absorbed (skin)

Why are organic solvents especially problematic neurotoxins?

They get into the BBB → lipophilic (dissolve thru fats like neurons)

What is Alzheimer’s disease most commonly associated with?

Dementia

Approximately what percent of people over 65 have Alzheimer’s?

10%

Approximately what percent of people over 85 have Alzheimer’s?

35%

What cognitive domains decline in Alzheimer’s disease?

Visuospatial, executive, memory, language

When is Alzheimer’s definitively diagnosed?

Autopsy (observe neurofibrillary tangles and amyloid plaques)

What is Parkinson’s disease?

Neurodegenerative motor disorder

What is the typical early onset age for Parkinson’s?

60 years old

Why is L-dopa used in Parkinson’s treatment?

To penetrate the BBB → turning into dopamine

What treatment is used after L-dopa stops working?

DBS (deep brain stimulation)

Which brain region degenerates in Parkinson’s disease?

Substantia nigra neurons

What is Huntington’s disease?

Genetic neurological disorder causing progressive brain cell death

What is the typical onset age range for Huntington’s disease?

30-50 years old

What gene is mutated in Huntington’s disease?

Huntingtin gene

What is the inheritance pattern of Huntington’s disease?

Autosomal dominant (only one copy needed)

What is chorea?

Dense in greek → describes movements of Huntington’s patients that are involuntary and excessive

What structural brain change is noted in Huntington’s disease?

Enlarged ventricles

What is the main goal of Huntington’s treatment?

Reduce symptoms thru lowering dopamine levels

What is multiple sclerosis?

Autoimmune disease affecting the nervous system, attacks CNS myelin (oligodendrocytes)

Why are early MS symptoms often visual?

Optic nerve is thinner → more vulnerable

Is MS primarily genetic?

No, environment (vitamin D exposure) and virus exposures play a role

What is epilepsy?

Neurological condition, reoccuring seizures