The hormone that controls the body's hunger pangs may also boost the memory, according to Scottish scientists.
Scientists have been looking at the hormone that controls hunger
Researchers at Dundee University have found a link between the hormone leptin and the brain's memory and learning process.
Leptin controls food intake and body weight and staves off the urge to eat.
The study was carried out by a team which specialises in the braincell processes that produce learning and memory.
Jenni Harvey, one of the researchers, said: "The hormone leptin, which is known to control food intake and body weight, has been shown to exert a profound influence on learning and memory processes in a region of the brain called the hippocampus.
"Leptin enhances the level of communication between brain cells in the hippocampus in a process known as long-term potentiation (LTP)."
It has been shown previously that people suffering from obesity have defects in their leptin levels and in the LTP process.
The group's findings could therefore shed light on how obesity affects learning and memory.
Dr Harvey said: "Defects in either leptin or genes that regulate leptin result in obesity and also cause impairments in LTP."
The team is currently examining the precise mechanisms that are responsible for the effects of leptin on LTP.
The findings are being presented at the annual BioScience conference, being held in Glasgow until Thursday.