Why bigger is better when it comes to our brain and memory

December 21, 2011

The hippocampus is an important brain structure for recollection memory, the type of memory we use for detailed reliving of past events. Now, new research published by Cell Press in the December 22 issue of the journal Neuron reveals characteristics of the human hippocampus that allow scientists to use anatomical brain scans to form predictions about an individual's recollection ability. The new research helps to explain why this relationship has been hard to find in the past and provides evidence for a possible underlying mechanism.

The hippocampus, a deep named for its curving seahorse shape, can be divided into anterior and posterior portions. Although research has generally linked smaller hippocampi with worse recollection in neuropsychological patients and during aging, this relationship has not held up among healthy . "There is some evidence that extensive acquisition leads to enlargement of the posterior hippocampus and a decrease in the anterior hippocampus," explains lead study author, Dr. Jordan Poppenk who conducted the study at Baycrest's Rotman Research Institute. "This suggested to us that the crucial predictor of individual differences in recollection ability might not be the overall size of the hippocampus but the separate contributions of the posterior and anterior segments of the hippocampus."

Dr. Poppenk and coauthor Dr. Morris Moscovitch analyzed high-resolution brain scans of healthy adults who had participated in recollection memory tests. Better recollection was associated with a larger posterior hippocampus and a smaller anterior hippocampus. The overall size of the hippocampus did not predict recollection, as larger posterior hippocampi were offset by smaller anterior hippocampi. The researchers went on to show that the link between the posterior hippocampus and recollection depended on interactions with other parts of the brain between the times that memories were learned and retrieved, particularly regions involved in perception which form the basis of recollected experience.

"Our results show for the first time that the size of the posterior hippocampus, especially when expressed as a ratio to the size of the anterior hippocampus, reliably predicts recollection in healthy adults. This finding explains the longstanding failure to correlate the overall size of the hippocampus with memory," concludes Dr. Poppenk. "We also provide evidence that it is the functional connections, possibly related to memory consolidation, between the posterior hippocampus and other that may underlie enhanced memory recollection."

Explore further: Hippocampus plays bigger memory role than previously thought

Related Stories

Hippocampus plays bigger memory role than previously thought

November 1, 2011

Human memory has historically defied precise scientific description, its biological functions broadly but imperfectly defined in psychological terms. In a pair of papers published in the November 2 issue of The Journal of ...

Recommended for you

Creative people have better-connected brains, research finds

February 21, 2017

Seemingly countless self-help books and seminars tell you to tap into the right side of your brain to stimulate creativity. But forget the "right-brain" myth—a new study suggests it's how well the two brain hemispheres ...

A novel principle to mobilize neurons for brain repair

February 21, 2017

Restorative neuroscience, the study to identify means to replace damaged neurons and recover permanently lost mental or physical abilities, is a rapidly advancing scientific field considering our progressively aging society. ...

Research reveals how the brain remembers fearful experiences

February 20, 2017

Understanding how the brain remembers can one day shed light on what went wrong when memory fails, such as it occurs in Alzheimer's disease. Researchers at Baylor College of Medicine and Rice University reveal for the first ...

Mercury in fish, seafood may be linked to higher risk of ALS

February 20, 2017

Eating fish and seafood with higher levels of mercury may be linked to a higher risk of amyotrophic lateral sclerosis (ALS), according to a preliminary study released today that will be presented at the American Academy of ...

Stem cell transplants may help some with multiple sclerosis

February 20, 2017

(HealthDay)—Stem cell transplants may halt the progression of aggressive multiple sclerosis (MS) in nearly half of those with the debilitating disease, but picking the right patients for the treatment is key, a new study ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.