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