Cognitive Psychology Practical

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Aim: to investigate the acoustic similarity of words and the effect on short term memory

Background: Baddeley has argued that short term memory is largely acoustic, therefore acoustically similar sounding words were more difficult to encode

Hypothesis: There will be a difference in the number of words recalled by participants when given a list of acoustically similar sounding words and a list of acoustically dissimilar sounding words.

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Method/ Procedure

Conducted a memory test on 7 boys and 7 girls aged 16-18 to see whether having acoustically similar or acoustically dissimilar words affects short term memory

On 2 powerpoints there was be 10 slides; each slide had a word on it (one powerpoint has a list of acoustically similar words such as cat, hat, mat and the other powerpoint had a list of acoustically dissimilar sounding words such as pen, mill, hit)

One powerpoint at a time, ppts were shown each slide for 3 seconds each slide

After that ppts were given a distractor task in which they were asked to name 10 objects in the room

After that, ppts were asked to recall as many words from the powerpoint as they could and write them down (regardless of order)

We then collected their lists and moved onto the next power point following the same process

Repeated measures experimental design (every ppt does both conditions of the IV)

We used a split half experimental design in which half did the one powerpoint first and then the other one and the other half did it the other way around - avoids order effects

Ppts selected using opportunity sampling

Controlled environment and procedure

We created a consent form and debrief sheet - avoids ethical issues

Results were put into a table, a bar graph and a Wilcoxon test was carried out

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Conclusions:

The general trend in the data for both males and females is that the number of acoustically dissimilar words remembered is higher than the number of acoustically similar words remembered however there is not a significant difference between the 2 conditions of the IV. This is different to what the alternate hypothesis predicted and suggests that the null hypothesis should be accepted. It tells us that there is no difference between the number of acoustically similar words recalled and the number of acoustically dissimilar words recalled.

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Evaluation

Strengths:

No gender bias

Minimal ethical issues - consent and debrief form

High levels of control - internal validity and replicability

Multiple researchers - inter-rater reliability

Application - Baddeley's experiments/ theories, help with dementia/ dyslexia

Weaknesses:

Can't generalise to all ages - only 16-18 year olds

Small sample - 14 ppts

Culture bias - UK

Artificial - low ecological validity

Demand characteristics

Possible embarrassment

Some use of deception

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Improvements:

Use independent groups - avoid order effects and increase internal validity

Larger sample - increased population validity, increased generalisabilty - more representative sample

Larger age range