Evaluate two models or theories of one cognitive process with reference to research studies

Atkinson-Shiffrin Multi-Store Model (1968)
This memory model splits memory into 3 distinct categories: Sensory memory (3 seconds), Short Term Memory (3s-3m) and Long Term Memory (long/unlimited). STM transfers into LTM from repeated rehearsal. Sensory memory is visual, while LTM is more semantically based. STM is characterized by active neurological activity, while LTM is a result of the creation of new synapses. This section could be expanded.

Strengths

 * Face validity (is this valid?). That is, it is a plausible explanation that accounts for the benefits of rehearsal in long-term memory storage. Rehearsal is a generally accepted phenomenon of memory.


 * However, this is true for several memory models.
 * Can explain the primacy effect – words at the beginning of the list for recall are chronologically displayed first, giving the subject more time to rehearse.


 * Doesn't explain recency effect, however.

Limitations

 * The model is too linear – cannot accommodate subdivisions of STM and LTM memory stores.


 * Clive Wearing had retrograde amnesia. He could not remember facts, such as his son's name. However, he could remember how to play the piano. This suggests separate divisions of long term memory: procedural (playing the piano) and semantic (factual memory).
 * The model does not account for the complexity of the information.
 * It does not account for the factors of an individual. A person trained to utilize a certain learning technique would have an easier time transferring memory into LTM, rather than the model’s broad generalization. (sketchy)
 * Savants such as Kim Peek transgress this model by encoding directly into LTM without rehearsal.

Craik-Lockhart Levels-of-processing Model (1972)
Rather than three distinct categories, the levels-of-processing model proposes a continuous continuum of memory encoding. Here, the depth of storage is dependent on the depth procesing. Visual processing (e.g. what does this word sound like?) results in shallow encoding. However, semantic processing (e.g. what does this word mean?) results in a deeper encoding. (You can expand on this)

Strengths

 * Empirical evidence: Kapur et. al (1994) used fMRIs and PETs to compare shallow processing with deeper processing in accordance with the Craik Lockhart model. More left prefrontal cortex activity was showed when subjets were asked to semantically process information, rather than visual or auditory.
 * However, more prefrontal cortex activity does not necessarily mean the memory is better encoded
 * Age-related memory degradation and Alzheimer’s disease reinforces this levels-of-processing effect. Older subjects and younger subjects were asked to visually process data. Older subjects showed poorer retention. However, older subjects performed closer to the younger subjects when asked to process semantic information. Grady and Craik (2000)

Limitations

 * Makes no mention of the properties of rehearsal, a generally accepted aspect of memory, where rehearsal improves retention.
 * In autism, levels of processing are reversed, showing the model’s inconsistency. Bertone et. al (2005) showed that non-semantically processed information was better encoded in autistics than others. Of course, it is necessary to consider that autism is in itself an inconsistency. No clear conclusions have been drawn.