Sebastian and Hernandez-Gil

• Aim 1:

  ~Investigate the development of the phonological loop in children between the ages of 5 - 17 years using digit span as a measure of phonological capacity
• Aim 2: 


  Check the decline of digit span in older people who suffered from dementia (Alzheimers & fronto-temporal dementia)
• Aim 3

  To see if Anglo-Saxon data - found that 15 years is where digit span stops developing further is replicated or higher in Spanish speakers ~Due to word length affecting the digit span (Spanish word length differs form Anglo-Saxon)
• Procedure: Part 1: What type of data is gathered?

  Primary data
• Procedure: Part 1: Why is primary data gathered?

  ~To test the hypothesis 'that there is a difference in digit span which increases with age from 5 -17 years old'
• Procedure: Part 1: Sample

  ~570 volunteers aged 5-17 ~Spanish population ~From various schools in Madrid ~No participants had repeated a school year, had learning difficulties ~Creates control
• Procedure: Part 1: How many groups where the children split into?

  ~ 5 age groups ~ Age 5, 6-8, 9-11, 12-14, 15-17 ~ Covers 13 year groups ~ Measure average digit span
• Procedure: Part 1: IV / DV

  IV = age of participants DV = digit span
• Procedure: Part 1: When where the participants tested?

  ~At break time and they were tested individually ~The sequences were read aloud, 1 per second
• Procedure: Part 1: What happened if they read the sequence correctly?

  ~Added another digit to increase the span and participants would try again ~The digit span for participants was recorded as the maximum digit recalled in the correct order without error
• Procedure: Part 2: What type of data was collected?


  ~Secondary data from previous study in 2010
• Procedure: Part 2: Sample

  ~25 healthy older people (control) ~25 people with alzheimers disease ~9 people with fronto-temporal dementia ~~Data gathered on the digit span of each group
• Procedure: Part 2: What was kept the same as part 1?


  ~The span task
• Results: Compared - Elderly Participants


  ~Elderly participants - higher digit span compared to the 5 year old in this study - not significant of other age groups
• Results: Compared: Alzheimers disease

  They showed similar profile to the 5 year olds
• Results: Compared: Fronto-temporal Dementia


  Digit span significantly similar to younger groups
• Conclusion: 1

  • Digit span increase with age from 5 - 17
  • Contrasts Anglo-saxon data as other studies demonstrated that digit span increased to 15 years and then reached an adult level.
  • Adult span - 7 digits
• Conclusion: 2

  • Spanish words are longer than English words
  • Sub-vocal rehearsal doesn't start until age 7 and so there should be less difference between English and Spanish children under 7 compared to over 7.
  • English studies have found a digit span of around 4 for age 5-6 years, comparable to Spanish children of that age.
  • Therefore, subvocal rehearsal could be the cause of the difference in older people.
  • From age 7, digit span increases with age for both English and Spanish participants but the digit span is about one digit lower for Spunch because of the effect of word length.
• Conclusion: 3

  • Healthy older people had a digit span similar to 7 years olds, showing that digit span declines with age, although we are unsure at what age the decline starts.
  • The digit span of Alzheimer's and fronto-temporal dementia is not much different from healthy older people and is similar to a 6 year old.
  • Therefore, dementia did not seem to impact digit span.
  • The capacity of the phonological loop seems to be affected by age, but not dementia.