Quality matters the most for our memory

“Our findings show that we don't simply store a set number of items and then recall them near-perfectly,” said Weiji Ma, an associate professor in New York University’s Department of Psychology.

“Rather, we try to memorise all relevant objects but the quality of these recollections is uneven and gets worse as we have to remember more,” added Ma, senior author of the study.

Working memory (WM) has a similar function as random access memory (RAM) in computers but its mechanisms are not nearly as well understood.

In recent years, psychology researchers have come to contrasting conclusions on the limits of working memory. Some have said there is a fixed number of memories we can store - for example we may be able to store the positions of only four different cars in our working memory at any given time.

But others have maintained that working memory's storage is not defined by the number of items it can hold and that its limits are better defined by the quality of memories.

In an effort to resolve this debate, Ma and colleagues examined data from 10 previously conducted experiments.

In a typical experiment, participants were asked to recall one of up to eight colours they had seen a few seconds ago - a well-established measurement for gauging memory.

Their analysis showed that working memory capacity is best explained in terms of quality of memories.

This quality gradually diminished as participants were asked to recall more and more colours. “Our results certainly do not mean that you always remember everything that matters. However, 'remembering everything a little bit' seems much closer to the truth than 'remembering a few things perfectly and others not at all'," added Ma. The findings appeared in the journal Psychological Review.

Your memory rewrites the past to update the present

The elation you associate with the moment when you saw your beloved for the first time may just be a trick your memory is playing on you.Puzzled? Our memory plays tricks on us and it is far from accurate if compared with a video camera, reveals a study.

The memory plucks fragments of the present and inserts them into the past, add researchers from Illinois-based Northwestern Medicine.It rewrites the past with current information, updating your recollections with new experiences.

“When you think back to when you met your current partner, you may recall this feeling of love and euphoria,” said lead author Donna Jo Bridge, a postdoctoral fellow in medical social sciences at Northwestern University's Feinberg School of Medicine.

"But you may actually be projecting your current feelings back to the original encounter with this person."This is the first study to show specifically how memory is faulty. It shows the exact point in time when that incorrectly recalled information gets implanted into an existing memory.

To help us survive, Bridge said, our memories adapt to an ever-changing environment and help us deal with what's important now.“The memory is not like a video camera. It reframes and edits events to create a story to fit your current world. It's built to be current,” explained Bridge.

All that editing happens in the hippocampus, the study found.

The hippocampus, in this function, is the memory's equivalent of a film editor and special effects team. “The notion of a perfect memory is a myth,” said Joel Voss, assistant professor of neurology at Feinberg.

“The memory is designed to help us make good decisions in the moment and, therefore, memory has to stay up-to-date,” Voss added.