Individual Differences and Developmental Psychology in Memory

Individual Differences

The speed at which we can process information differs between individuals. Known as 'processing speed'. Due to differences in the speed at which people can process information and their short-term store capacity.

Processing speed and capacity is affected by age too. Younger children have a shorter digit span than older children, suggesting memory capacity increases with age.

Schemas and autobiographical memory (episodic memory) are also subject to individual differences. Bartlett's reconstructive memory theory suggests that we all have relatively similar schemas, but that these schemas can be heavily influenced by experience. This in turn affects the way we perceive information received by the senses and retrieve information held in memory. Similarly, the development of our schema will affect how we recall information.

Episodic memory is individual to the person as its a collection of memories of their own life; an autobiography of personalised events.

Palombo (2012)

598 ppts (volunteers) Conducted a survey of Autobiographical memory designed to assess individual differences in naturalistic autobiographical memory They subdivided autobiographical memory into 4 domains: episodic memory, semantic memory, spatial memory and prospective memory (imagination for future events) The questionnaire contained 102 items which ppts scored on a 5 point likert scale

Findings: Individuals who scored high or low on episodic memory also scored high or low on semantic memory. So we either have good or poor memory overall Palombo et al. also found that men scored higher on spatial memory; this finding is consistent with other research indicating that men have stronger spatial ability than females Also found that people who self-reported having depression scored low on episodic and semantic memory

Weaknesses: Self-report (social desirability bias/ demand characteristics) Biased/ leading questions Likert scale is very reductionist - limits their responses

Developmental Psychology in Memory

Developmental psychology investigates what happens to us as we age and concerns both normal and abnormal behaviour In memory research, Dyslexia and Alzheimer's Disease have been investigated in young and old ppts.

Dyslexia

Affects between 3 and 6% of children Is more prevalent in boys than girls Characterised by having a particular difficulty with phonology which is critical for learning to read Poor verbal short-term memory Evidence for this comes from the phonological similarity effect and the word length effect Perhaps they have impaired STM memory to deal with speech sounds

McDougall et al. (1994)

Divided 90 children into 3 different reading ability groups: poor, moderate and good readers

Found that poor readers had significantly lower memory spans for words and slow reading rate Good readers can articulate words quickly, leading to a greater number of words being represented phonologically in STM Poor readers sound out words more slowly, leading to fewer words being held in STM

This basic inefficiency in phonological processing and storage may explain dyslexia

Alloway et al. (2009)

Suggests children with dyslexia have poor working memory They can't hold all the speech sounds for long enough in working memory to be able to form a word (not enough capacity to store syllables for long enough to form them into a word)

Investigating 46 children, aged 6-11 years, with reading disability, she found that they showed ST working memory deficits that could be the cause of their reading problems.

Smith-Spark et al. (2010)

Found adults with dyslexia had unimpaired spatial working memory but impaired verbal working memory, compared to a control group of non-dyslexic ppts Suggests impaired phonological loop

Research seems to conclude quite strongly that children and adults with dyslexia have an underlying cognitive impairment leading to a shorter memory span and difficulty processing and storing verbal info in STM.

Ways to help with Dyslexia

Can't process words/speech very well so they could use images instead for learning. Give them extra processing time in tests/exams. Change learning strategies so they do more practical activities. Put sentences, information into chunks so it's easier for them to process. Teach children to sound out words - build up capacity of phonological loop.

Problems with Dyslexia Research

Difficult to establish what role verbal memory plays in causing dyslexia, particularly because people with dyslexia present a range of sensory impairments in both auditory and visual systems. Dyslexia is comorbid with other learning difficulties, such as attention deficit hyperactivity disorder (ADHD) therefore it's difficult to isolate a reason for reading impairment.

Alzheimer's Disease

A progressive, degenerative, neurological disorder associated with ageing Will affect 1 in 20 people Risk of development increases with age Most common form of dementia Can occur after 65 years or as early as 40 Memory loss, concentration loss, confusion and changes in mood that become progressively worse Selectively impairs cognitive systems rather than deteriorating cognition globally (new events and information whereas older info is preserved) Affects WM - central executive becomes impaired, making complex tasks more difficult to co-ordinate and visuo-spatial processing becomes impaired Inability to recall autobiographical info from episodic memory - affects ST and LT recall Memory loss associated with loss of brain matter, particularly in hippocampus and temporal cortex - typically increases with progression of disease

Baddeley et al. (2001)

Conducted a series of attention tests on individuals with Alzheimer's and control ppts, involving looking for the letter 'Z' among easy and difficult distractor letters, and a dual task procedure.

Found ppts with Alzheimer's performed worse on the difficult distractor task and were more impaired on the dual task. Suggests dual tasks are specifically impaired by the disease.