PSYCH 243 (Introduction to Behavioral Neuroscience) Chapter 24

Dissociative Amnesia

- Amnesia with no other cognitive deficit (rare); no brain damage - Loss of information about personal identity or experiences; often stress-related

Why were Lashley's conclusions incorrect?

- Different cortical areas do not contribute equally to learning and memory - However, it is true that memories are distributed across regions

(1920's) Lashley's Studies of Maze Learning in Rats

- Experiment on associating memory with regions of the cortex - Lesioned various regions of cortex and trained until rats learned the maze and vice versa

Memory

The persistence of learning over time through the encoding, storage (retention), and retrieval of information

Cell assembly

a group of simultaneously active neurons that are reciprocally interconnected and represent an object held in memory

Transient Global Amnesia

a sudden onset of compete anterograde amnesia and learning abilities (minutes-days) , pronounced retrograde amnesia, preservation of memory for personal identity, anxious awareness of memory loss with repeated and often perseverative questioning, overall normal behavior

Anterograde Amnesia

an inability to form new memories

Retrograde Amnesia

an inability to retrieve information from one's past

What does memory loss reflect?

changes in memory storage over time

Causes of Amnesia

disease, concussion, alcoholism, encephalitis (inflammation), tumor, stroke

What is the physical representation of memory?

engram (memory trace, representation)

Donald Hebb's Proposal

human learning takes place by neurons forming new connections with one another or by the strengthening of connections that already exist

Procedural Memory (Implicit)

long-term memory of how to perform different actions and skills

Striatum

major input of the basal ganglia (caudate nucleus and putamen)

Explicit Memory

memory of facts and experiences that one can consciously know and "declare" (conscious recollection) (medial temporal lobe, diencephalon)

Declarative Memory

memory of knowledge that can be called forth consciously as needed

Non-declarative Memory

memory of knowledge that cannot be called forth consciously as needed; memory demonstrated in behavior

Implicit Memory

retention independent of conscious recollection

Causes of Transient Global Amnesia

seizures, stress, drugs, trauma, toxins (what if it's due to a block in blood flow?)

Amnesia

serious partial or total loss of memory and/or ability to learn

Working Memory

short-term memory that focuses on conscious, active processing of incoming sensory information, and of information retrieved from long-term memory

Where is memory stored and what is it stored as?

stored in/as: neurons, circuits: firing pattern, synapses

Learning

the process of acquiring new and relatively enduring information or behaviors