Cognitive Psychology: STM, WM, LTM Structure

Study Notes

This lecture covers the structure of short-term memory (STM), working memory (WM), and long-term memory (LTM).
Cognitive Psychology, PSYCH 258 A3, Fall 2024 lecture by James Farley.

Failures of the central executive (CE) can lead to perseveration, repeating actions or thoughts even if they're unproductive.
An example of this in studying: sticking to a study method that didn't produce favorable results, even when other methods are potentially more beneficial.
One criticism of the CE is its resemblance to a "homunculus," a hypothetical, miniature person within the brain that performs complex functions, lacking specific details about how these functions are achieved.

An episodic buffer was added to the three-part working memory model to account for the fact that humans can hold more information than initially estimated by the model's components.
This component acts as a 'backup' buffer.
It temporarily stores information retrieved from long-term memory (LTM) until the central executive allocates it to one of the other working memory components.
Pre-loading complex information that exceeds the phonological loop's capacity.

The prefrontal cortex is responsible for processing incoming visual and auditory information.
Monkeys without a prefrontal cortex have difficulty holding information in working memory.
This is demonstrable through the use of a delayed-response task.

Individual differences in working memory capacity were established through experiments, assessing participants as either high or low capacity.
Participants were shown simple or complex stimuli with or without distractors.
Electroencephalography (EEG) (ERP) responses were measured to quantify participants' responses to the presented stimuli in order to understand how the brain processes information.

High-capacity participants demonstrated less of a response to distractors.
This implies a more efficient filtering/inhibition of distractions in high-capacity participants, a capacity potentially attributable to strengths of their central executive.

Long-term memory (LTM) is a vast storehouse of information about past events and knowledge.
LTM works alongside short-term/working memory components.
The diagram represents various component data categories, potentially including experience, concepts, facts,goals.

LTM archives information from past events and acquired knowledge.
It works closely with short-term/working memory.
LTM storage encompasses a range of moments from recent events to distant past ones.
More recent memories tend to be more detailed than those further in the past.

Murdoch (1962) investigated the distinction between short-term memory and long-term memory using the serial position curve.
Participants read and recalled lists of stimuli.
Participants exhibited better memory recall for stimuli presented at the beginning (primacy effect) and the end (recency effect) of the list.

The primacy effect is likely due to having more time to rehearse and encode the first terms in the series.
The recency effect is thought to stem from the continued storage of stimuli in short-term memory .

Coding refers to the form information is represented; visual, auditory, and semantic codes exist.
In Short-Term Memory (STM), auditory coding is common.
In Long-Term Memory (LTM), semantic coding (based on meaning) is common.