sebastian + hernandez gill - cognitive

• aims of experiment (3)

  1 - to study development of phonological loop in children aged 5-17

  2 - to see whether digit span increased with age in the same way it did with english native speakers

  3 - to compare digit span of this age group with previous research with adults, the aged, and dementia patients
• what had previous research shown (3)

  1 - phonological loop present by age 3-4

  2 - subvocal rehearsal present from age 7-8

  3 - anglo-saxon digit span increased to 15 years old
• who were the participants, how many

  570 volunteers, native Spanish children from schools in Madrid aged 5-17
• procedure


  1 - participants split into age groups

  2 - sequences of digits read out to them at a rate of 1 digit per second, list length increased by 1 digit per sequence

  3 - participants had to recall the digits in sequential order

  4 - digit span recorded as maximum number of digits in a sequence recalled without error
• control variables


  . ability of children - reading, writing, hearing, language, ect

  . rate of digit presentation

  . standardised procedure
• who was excluded from the experiment

  children with impairments
• what was the experimental design

  independent groups
• independent variable


  age
• dependent variable


  recall of digits in sequential order
• results (2)

  1 - digit span slowly rises until around age 11, then continues to rise slowly until adulthood

  2 - overall digit span lower in spanish population compared to english - possibly due to pronunciation time due to more syllables in spanish numbers
• conclusions


  . subvocal rehearsal appears at 7-8 years old - means pronunciation time then becomes a significant factor in digit span
• how was the conclusion found

  there was no difference in digit span between spanish and english speakers until age of 7, then a noticeable difference at 9
• how were results compared to previous research

  . the aged previously found to have similar digit span to those with advances dementia

  . suggests that poor digit span in dementia patients is a consequence of aging , not dementia

  . the aged has a higher digit span than 5 year olds in this study
• generalisation pros (2)


  . large sample (570), male and female so no gender bias = more representative

  . sample of spanish participants made comparison with english possible
• generalisation cons (4)


  . participants volunteered so could have ulterior motive for participating

  . participants from Madrid schools only = children not representative of other regions

  . can't generalise findings to other language and cultures

  . participants with impairments excluded so is impossible to generalise findings to that group
• reliability


  . standardised procedure used eg presentation of digits 1 per second = good internal reliability

  . is possible to replicate so external reliability of findings can be measured
• application (2)


  . use of measures of digit span to detect dyslexia

  . limited digit span of younger children may be important for teachers of primary school aged children
• validity pros


  . possible confounding variables controlled making it easier to infer cause and effect relationship between age + digit span = good internal validity
• validity cons


  . lack of ecological validity - recalling digits is not an everyday task
• validity conclusion


  further research needed to investigate more everyday learning
• ethics


  . participants were children so unable to give informed consent

  . protection - children could be upset with a lower than average score
• ethics conclusion


  . benefits of the research in terms of scientific benefits and applications outweigh the relatively low ethical cost