In experiments using functional magnetic resonance imaging (fMRI), the scientists were able to view what happened in the brains of subjects when they experienced an event made up of multiple contextual details. They found that participants who later remembered all aspects of the experience, including the details, used a particular part of the brain that bound the different details together as a package at the time the event occurred. When this brain region wasn’t activated to bind together the details, only some aspects of an event were recalled.
The scientists presented 23 research subjects with a list of words while they underwent an fMRI scan. The words were in different colours and would appear in one of four quadrants on a screen. The subjects had to decide whether the words represented an animate or inanimate object. Later, the participants were presented the words again, interspersed with words they had not seen before, and asked if they remembered seeing those words before. They were also asked if they remembered in what colour the word had originally been and in which of the four quadrants it had originally appeared.
If the participant could later remember the colour of the word, a particular area of the brain associated with colour processing was especially active during learning. If the subject later remembered the location of the word, activity was seen in an area associated with spatial processing. But if the subject remembered the word, the colour and the location, then another critical brain region became involved.
The researchers observed enhanced activity in the intra-parietal sulcus, a part of the parietal cortex. It appears that this region is responsible for binding together all the features of a particular memory so that contextual details, as well as more central aspects of the event such as the identity of the word, can later be recalled.
MEDICA.de; Source: University of California, Irvine