Memory tests show that most people can only remember three or four things if allowed only a glimpse of an image. This is the short term working memory.

Our short term working memory may be processed in a very small, specific area in the brain giving rise to a “bottle neck”, according to two studies reported in the journal Nature.

Studies led by Edward Vogel of the University of Oregon found that the electrical activity in a single area of the brain is directly related to working memory.

Another study led by René Marois of Vanderbilt University in Nashville used fMRI, a different investigation technology, during similar mental task test to locate the active parts of the brain.

Both studies reported that they had zoomed in to the same tiny spot in the posterior parietal cortex.

The result came as a surprise to both since researchers were expecting that a working memory test, which involves processing of spatial position, orientation, and color, would involve multiple areas of the brain.

They suggested that this convergence to a tiny area may mean that we have a short term working memory “bottle neck”, which limits capacity. More research is needed to confirm and clarify the findings.