Primacy and recency effects refer to the better performance or shorter response time on the first and last items than the middle ones of a memory list. In order to investigate its neural basis in auditory short-term memory, event-related fMRI was used to measure brain activities when subject was recalling the first, the last, or the middle items. Recalling the middle item was associated with more extensive activation in the left parietal and visual cortex, basal ganglia, and dorsal cerebellum. Recalling items from different serial positions also resulted in different activation time courses in the bilateral primary auditory cortex, left prefrontal cortex and left premotor cortex. These data indicate that the auditory cortex may serve as a transient storage or the auditory input buffer, which seems to play an important role in the primacy and recency effects.
Bibliographical noteFunding Information:
This research is supported by the National Nature Science Foundation of China (39928005, 39970253), National Basic Research Program of China (G1998030509), Outstanding Overseas Chinese Scholars Fund of CAS, and NIH (grant number RO1MH55346).
- Event-related fMRI
- Serial position effect
- Short-term memory