People who want to have better memory retention should look to have more sleeping time, according to a new research.
Scientists at the Scripps Research Institute (TSRI) have found that sleep helps suppress the function of nerve cells that cause forgetfulness in people.
Ronald Davis, chair of the neuroscience department at TSRI and lead investigator of the study, said that while previous research have tried to determine how people learn and retain information, less focus was given on the effects of forgetting, which is a primary function of the brain. This could also potentially affect the development of therapeutics for memory.
Davis added that their research combines the neuroscience of forgetting, which is the study of how the brain is able to forget information, and the psychology of forgetting into a singular concept.
In earlier studies, researchers suggested that sleep allowed the brain to retain memory by eliminating interference produced by behavioral and mental activity. The act of sleeping basically isolates the individual's brain from all stimuli that could possibly hinder the storage of memory.
Studies in neuroscience, however, suggest that sleeping provides an opportunity for the brain to retain memory by improving the stability of the memory through a process known as consolidation.
Davis and his team focused on the biological foundations of previous studies in psychology especially the activity of dopamine, a neurotransmitter that helps the brain send signals to key points in the body.
The researchers noted that dopaminergic activity is responsible for regulating the different forms of plasticity, or the brain's ability to adapt to learning and the formation of memory. They also identified that this ability also facilitates the forgetting of memories as well.
Findings show that increased sleep, either through stimulation of the sleep circuit of the brain or sleep-promoting drugs, helps reduce the signaling activity of dopamine while improving the retention of memory as well.
An increase in arousal, on the other hand, helps raise the activity level of dopamine and accelerates the process of forgetting. The researchers noted that this activity does not always happen, but it is directly connected to the arousal activity of the test animal used in the study.
"Our findings add compelling evidence to support the model that sleep reduces the forgetting signal in the brain, thereby keeping memories intact," Davis explained.
"As sleep progresses to deeper levels, dopamine neurons become less reactive to stimuli and this leads to more stable memories."
The researchers highlighted that the potential effects of sleep on the consolidation of memory and the process of forgetting could occur parallel to or independently of one another. These could also occur dependently, wherein a reduction in the rate of forgetting serves as a requirement for consolidation through sleep.
The Scripps Research Institute study is featured in the journal Cell.
Photo: Pedro Ribeiro Simões | Flickr
