False recognitions in short-term memory - Age-differences in neural activity.

Area of Science:

• Cognitive Neuroscience
• Neuroimaging
• Human Aging Research

Background:

• Episodic memory research extensively documents age-related differences in false memory susceptibility.
• Little is known about age effects on false memories within visual short-term memory (STM).
• Previous behavioral findings indicated older adults are more confident in, but not necessarily more prone to, erroneous STM recognitions.

Purpose of the Study:

• To investigate the neural correlates of age-related differences in visual short-term memory (STM) false recognitions.
• To compare brain activity patterns between younger and older adults during tasks involving false recognitions in STM.
• To explore the relationship between frontal activity, performance, and metacognitive abilities in age-related STM false recognition.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was employed to measure brain activity.
• Participants performed a visual short-term memory recognition task designed to elicit false recognitions.
• Behavioral data on recognition accuracy and confidence ratings were collected and analyzed alongside fMRI data.

Main Results:

• Behavioral results replicated previous findings: older adults were more confident in false recognitions than younger adults, with no significant age difference in false alarm rates.
• Younger adults exhibited greater activation in visual cortex, anterior cingulate cortex (ACC), frontal operculum/insular cortex, and prefrontal cortex regions during false recognitions compared to older adults.
• No age differences in hippocampal activity were found. Younger adults, unlike older adults, showed increased ACC and frontal operculum/insular cortex activity for false recognitions versus confident correct rejections. Frontal activity correlated with performance and metacognition.

Conclusions:

• Age-related differences in confidence for STM false recognitions may stem from distinct age-related processes in performance monitoring and uncertainty processing.
• These findings suggest that the neural basis of confidence in STM false recognition differs between younger and older adults.
• The results highlight that age-related changes in memory confidence are not solely dependent on hippocampal function but involve broader frontal executive control networks.