Medical Research Council - London Institute of Medical Sciences

Now in our 12th year of bringing you beautiful imagery from biomedical science every day

Happy Memories
31 July 2015

Happy Memories

Our mood is believed to be linked to a part of the brain called the hippocampus, but this connection isn’t fully understood. The hippocampus is known to be important for the regulation of short and long term memory, suggesting a relationship between memory and mental health. Researchers monitored the brain activity of male mice exposed to positive and negative experiences – they were introduced to female mice, and temporarily placed in a confined space. Pictured is a comparison of the brain activity during the positive (top) and negative (bottom) experiences – the stimulated brain cells can be seen from the red glow as they fire neurons. Memory cells which were activated only during the positive experience were identified and stimulated by light to ‘reactivate’ the positive memory in stressed mice. This was shown to suppress depression-like symptoms, providing insight into the mechanisms behind mental health disorders such as depression and anxiety.

Written by Helen Thomas

Search The Archive

Submit An Image

What is BPoD?

BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

Read More

BPoD is also available in Catalan at with translations by the University of Valencia.