Featured Research

from universities, journals, and other organizations

Have I Been Here Before? Neuronal Mechanism Could Help Explain Déjà-vu

Date:
June 8, 2007
Source:
University of Bristol
Summary:
"Have I been here before?" In today's fast-moving world of look-alike hotel rooms and comparable corridors, it can take a bit of thinking to answer this simple question. Scientists say that they have identified a neuronal mechanism that our brains may use to rapidly distinguish similar, yet distinct places.

Dentate gyrus pattern.
Credit: Matt Jones

"Have I been here before"? In today's fast-moving world of look-alike hotel rooms and comparable corridors, it can take a bit of thinking to answer this simple question. University of Bristol neuroscientists working with colleagues at the Massachusetts Institute of Technology (MIT) report in the June 7 early online edition of Science that they have identified a neuronal mechanism that our brains may use to rapidly distinguish similar, yet distinct places. The discovery may help explain the sensation of déjà vu.

The work could lead to treatments for memory-related disorders, as well as for the confusion and disorientation that plague elderly individuals who have trouble distinguishing between separate but similar places and experiences.

Forming memories of places and contexts in which episodes occur engages a part of the brain called the hippocampus. The laboratory of Nobel Laureate, Susumu Tonegawa, Picower Professor of Biology and Neuroscience at MIT, has been exploring how each of the three hippocampal subregions-the dentate gyrus, CA1 and CA3-contribute uniquely to different aspects of learning and memory. In the current study, co-authors Matthew Jones, Research Councils UK (RCUK) Academic Fellow in the Department of Physiology at the University of Bristol and Dr Thomas McHugh, a Picower Institute research scientist, have revealed that the learning in the dentate gyrus is crucial in rapidly recognizing and amplifying the small differences that make each place unique.

Dr Jones, commenting on the paper, said: "We constantly make split-second decisions about how best to behave at a given place and time. To achieve this, our nervous system must employ highly efficient ways of rapidly recognising and learning important changes in our environment.

"This paper demonstrates that a particular protein signalling molecule (the NMDA receptor) in a particular network of brain neurons (the dentate granule cells of the hippocampus) is essential for these rapid discrimination processes, hopefully paving the way for therapies targeting learning and behavioural disorders."

Professor Tonegawa, a frequent world traveler, describing his own occasional experience of finding the airport in a new city uncannily familiar, added: "This occurs because of the similarity of the modules-gates, chairs, ticket counters-that define the context of an airport. It is only by seeking out unique cues that the specific airport can be identified."

Researchers believe that a set of neurons called 'place cells' fire to provide a sort of blueprint for any new space we encounter. The next time we see the space, those same neurons fire. Thus we know when we've been somewhere before and don't have to relearn our way around familiar turf. But similar spaces may activate overlapping neuronal blueprints, leaving room for confusion if the neurons are not fine-tuned.

In this study, the researchers used a line of genetically altered mice to pinpoint how the dentate gyrus contributes to the kind of pattern separation involved in identifying new and old spaces. Whilst the mice behaved normally in most situations, they became confused when required to discriminate between different spaces. This may model the difficulties in forming distinct memories for similar but distinct places and experiences that afflicts some elderly individuals.

In addition to Dr Matthew Jones, Professor Susumu Tonegawa and Dr Thomas McHugh, authors include Matthew Wilson, Picower Scholar and Professor; and colleagues from the University of California at Los Angeles and Beth Israel Deaconess Medical Center in Boston.

This work was supported by the National Institute for Mental Health and the National Institutes of Health.


Story Source:

The above story is based on materials provided by University of Bristol. Note: Materials may be edited for content and length.


Cite This Page:

University of Bristol. "Have I Been Here Before? Neuronal Mechanism Could Help Explain Déjà-vu." ScienceDaily. ScienceDaily, 8 June 2007. <www.sciencedaily.com/releases/2007/06/070607171112.htm>.
University of Bristol. (2007, June 8). Have I Been Here Before? Neuronal Mechanism Could Help Explain Déjà-vu. ScienceDaily. Retrieved April 17, 2014 from www.sciencedaily.com/releases/2007/06/070607171112.htm
University of Bristol. "Have I Been Here Before? Neuronal Mechanism Could Help Explain Déjà-vu." ScienceDaily. www.sciencedaily.com/releases/2007/06/070607171112.htm (accessed April 17, 2014).

Share This



More Mind & Brain News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Are School Dress Codes Too Strict?

Are School Dress Codes Too Strict?

AP (Apr. 16, 2014) — Pushing the limits on style and self-expression is a rite of passage for teens and even younger kids. How far should schools go with their dress codes? The courts have sided with schools in an era when school safety is paramount. (April 16) Video provided by AP
Powered by NewsLook.com
Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) — A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. Video provided by Newsy
Powered by NewsLook.com
Couples Who Sleep Less Than An Inch Apart Might Be Happiest

Couples Who Sleep Less Than An Inch Apart Might Be Happiest

Newsy (Apr. 16, 2014) — A new study by British researchers suggests couples' sleeping positions might reflect their happiness. Video provided by Newsy
Powered by NewsLook.com
Cognitive Function: Is It All Downhill From Age 24?

Cognitive Function: Is It All Downhill From Age 24?

Newsy (Apr. 15, 2014) — A new study out of Canada says cognitive motor performance begins deteriorating around age 24. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins