2.3.4 - Sebastian and Hernandez-Gil (2012) Developmental pattern of digit span in Spanish population Flashcards
(11 cards)
what were the aims of the study?
to investigate the development of the phonological loop in children aged 5-17, using digit span to measure phonological capacity
to compare the research to that of adult, aged and dementia patients
what was the sample for the study?
570 volunteer/volunteered participants in all year groups from public and private schools in Madrid
they were all native Spanish
what was the procedure for the study?
- participants were divided into 5 age groups, and the average digit span was recorded for each age and age group
- individually, participants were read increasing sequences of digits to recall in the correct order (measured in classrooms during school breaks)
- digit span was recorded as the maximum digit recalled in the correct order without error
- digits were read out at a rate of 1 per second, with the digit list increasing one digit per sequence
what were the results of the study?
digit span increased with age, rising from 3.76 in pre-school to 5.91 in year 12
the increase occurred steadily from ages 5-11, and then slowed down, remaining more stable
what was seen when comparing the results to aged and dementia patients?
elderly patients had a significantly higher digit span than the 5 year olds, but it wasn’t significantly different to the other age groups (similar for patients with advanced dementia)
patients with frontal variant frontotemporal dementia had a digit span significantly similar to the younger group
there was no significant different between the elderly and dementia groups
what was seen when comparing the results to other cultures?
the overall capacity of digit span was lower in the Spanish population compared to Anglo-Saxon studies
this could be because Spanish digits are usually 2+ syllables while English ones are monosyllabic, so due to the word length effect it takes longer to sub-vocally rehearse Spanish digits, taking up more capacity in the phonological loop
sub-vocal rehearsal develops around aged 7- supported by the fact that before this age there was no difference in digit span before English and Spanish participants
what were the conclusions of the study?
digit span increases with age
the word length effect means digit span in Spanish populations is shorter than in English ones
poor digit span is likely due to ageing, not dementias
evaluation - generalisability?
strengths:
large sample size which also allows for comparison across cultures
weaknesses:
digit span experiments may lack mundane realism as we don’t normally use verbal memory to memorise lists of number (apart from phone numbers) - instead we use it to hold word sequences so we can understand sentences, learn languages and read complex information
evaluation - reliability?
strengths:
digit span tests have been reliably linked to performance in reading/intelligence - suggests they are good measure of verbal memory
standardised procedure used eg. digits read at same rate so study could be replicated to show reliability
evaluation - validity?
strengths:
tasks conducted in participant’s classrooms so setting has high ecological validity - somewhere they usually use memory/rehearsal
participants with hearing, reading or language impairments which could decrease digit span were excluded
researchers assessed digit span as longest digit list child could repeat correctly in two out of three trials (if they made error were given another chance with a different list) - means any random errors made wouldn’t cause underestimation of digit span
evaluation - supporting evidence?
other researchers have identified cultural differences in digit span which suggest language and the phonological loop are related eg. Stigler et al. (1986) - longer digit spans reported in Chinese populations because words for digits are short
