In sleep, memory creates our short-term space for new memories

Sleeping with a decisive influence on the storage of memories

Sleep is essential for our health and sleep deficits can lead to significant health problems. Also, the brain uses sleep to transfer memory content of the Hippocampus in the cerebral cortex and to create space in the short-term memory, the result of a recent study by researchers at the University of Tübingen.

The research team Lea Himmer, Dr. Monika Schönauer, and Professor Steffen Gais from the Institute of Medical psychology and Behavioral neurobiology at the University of Tübingen has studied in his recent study, “how the brain represents the tasks in the solidification of new Learning share and what is the role of sleep”, the communication of the University of Tübingen. The results of the study were published in the journal “Science Advances”.

In the sleeping memory contents are transferred from the Hippocampus into the cerebral cortex, resulting in short-term memory is free again for new information. (Image: Leszek glasner/fotolia.com)

The Hippocampus and cerebral cortex to store information

Our memory stores information in two regions of the brain, the Hippocampus and the cerebral cortex. The Hippocampus is used, especially in the short term, to absorb new information, while the cerebral cortex, the information can save amounts for a long time, explain the researchers. On the basis of imaging techniques were able to demonstrate in the current study, that within a short period of time through repeated Practice in the cerebral cortex of new memory traces can be built. It is only when a sleep phase follows, these are, however, transmitted entirely in the cerebral cortex. Without the sleep phase, the brain for permanent storage of the new memory content must also rely on the Hippocampus.

In their studies, the researchers observe the subjects in a learning task that you should memorize in seven repetitions of a word list. In Parallel, the activity of the brain with a magnetic resonance imaging (MRI) was recorded. After twelve hours, the subjects repeated the same task with the already-learned and a new word list, the communication of the University of Tübingen. While a half of the subjects had occasionally slept, was the other half of constant guard.

The Hippocampus was only after sleep phases uninvolved

The information provided by the researchers, repeated Practice led “within an hour, the trained using the posterior parietal lobe, a Region of the cerebral cortex, was obtained” and the involvement of the Hippocampus was reduced accordingly. “This pattern indicates a rapid formation of memory traces in the cerebral cortex,” Dr. Schönauer. However, the Hippocampus remains the only uninvolved, if the Participants had after the first session, several hours of sleep.

Sleep for memory is especially important

The subjects remained in between the wax was required in the case of already known words to continue the Hippocampus, explain the researchers. “We show that in sleep-memory processes that go beyond the pure Repeat,”; so Leah Himmer. Although learning reps can create long-term memory traces, but whether the content will be independent of the Hippocampus permanently stored, and would depend crucially on a sleep phase.

Interaction of the cerebral cortex and Hippocampus is unclear

The current investigation has shown that sleep affects mainly on the Hippocampus, and it remains to be seen, such as the Hippocampus and cerebral cortex play together, Steffen Gais, the head of the working group at the University of Tübingen. “To understand this interaction, is an important step in the development of popular theories of memory formation,” stresses Gais. How memory contents are stored in the cerebral cortex and what role the Hippocampus plays, also for the understanding of learning and memory disorders is of crucial importance.(fp)