1. Capacity - STM Span-measure studies of STM PPs given series of words, digits etc. PPs given series of words, digits etc. Immediate recall (accuracy and order) Immediate recall (accuracy and order) Lists get progressively longer Lists get progressively longer To obtain results, plot length of list against % correct recall www.psychlotron.org.uk

2. Capacity - STM 34567891011 % recall Length of list www.psychlotron.org.uk

3. Capacity - STM Generally it is found that PPs are able to recall between 5 and 9 chunks of information (i.e. 7±2 chunks) Miller (1956) and others suggested that this represented the capacity of STM A rule can be used to chunk information together, allowing STM to hold more (e.g. 4 digits can make a date) www.psychlotron.org.uk

4. Capacity - STM Some evidence that ‘chunk’ is not an appropriate capacity measure Simon (1974) found that as the size of chunks increased (e.g. 1, 2, 4 words) the number of chunks recalled decreased Simon (1974) found that as the size of chunks increased (e.g. 1, 2, 4 words) the number of chunks recalled decreased Findings from speakers of other languages suggest STM capacity is time limited not chunk limited Findings from speakers of other languages suggest STM capacity is time limited not chunk limited However, all the evidence points to STM having a limited capacity www.psychlotron.org.uk

5. Capacity - LTM STM is used for holding the small amount of information we are dealing with at any one moment LTM is the store for all our learning, so presumably has much larger capacity Actual LTM capacity is impossible to test experimentally but does not appear to be limited (i.e. functionally unlimited www.psychlotron.org.uk