Brain circuits update memories of other people

Social memory is the ability to recognise others and recall how previous interactions with them went. This memory is not a fixed record: it is continuously revised in light of new social experiences. How the brain executes this revision, called valence updating, has until now been poorly understood.

The researchers, publishing in Science, mapped the neural circuits responsible for updating the emotional charge attached to memories of specific individuals. They identified connections between brain regions that process social information and regions that assign emotional value to experiences. In mice, disrupting these circuits prevented animals from adjusting their social preference after a previously positive social partner began displaying negative behaviour.

Social flexibility and the aging brain

This kind of social learning requires not just memory but cognitive flexibility: the ability to revise existing representations based on new information. Cognitive flexibility is among the earliest functions to decline in age-related cognitive impairment and in conditions such as Alzheimer’s disease. Whether the circuits identified in this study are particularly vulnerable in aging has not been examined, but the question is scientifically relevant.

From mouse to human: interpret with caution

The findings are based on mouse experiments and cannot be directly extended to human social cognition, which is considerably more complex. Nevertheless, the circuits identified provide a starting point for understanding how social memory impairments, as seen in frontotemporal dementia or ordinary aging, might be understood at the circuit level. The study makes no therapeutic recommendations and explicitly acknowledges the limitations of the animal model.

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