The American Physiological Society Press Release

press release logo

APS Contact: Donna Krupa

Email: dkrupa@the-aps.org

Phone: 301.634.7209

Twitter: @Phyziochick

Working Memory and the Brain

Visual working memory not as specialized in the brain as visual encoding, study finds

Article is published in the Journal of Neurophysiology

Bethesda, Md. (February 6, 2012)—Researchers have long known that specific parts of the brain activate when people view particular images. For example, a region called the fusiform face area turns on when the eyes glance at faces, and another region called the parahippocampal place area does the same when a person looks at scenes or buildings. However, it’s been unknown whether such specialization also exists for visual working memory, a category of memory that allows the brain to temporarily store and manipulate visual information for immediate tasks. Now, scientists have found evidence that visual working memory follows a more general pattern of brain activity than what researchers have shown with initial visual activity, instead activating a more diffuse area in the front of the brain for all categories of visual stimuli.

The study is entitled "Mapping Brain Activation and Information During Category-Specific Visual Working Memory." It appears in the Articles in PresS section of the Journal of Neurophysiology, published by the American Physiological Society.

Methodology

The researchers worked with 18 healthy adults with normal or corrected vision. Using functional MRI (fMRI), a technique that examines brain activity while subjects are actively performing tasks in an MRI scanner, the researchers had each volunteer view and memorize three sequentially presented images that represented one of four categories: faces, bodies, scenes, or flowers. Between each image, there was a one second delay. Then, after a 10 second delay, the researchers flashed an image from the same category and asked the volunteers to indicate through a button press whether this last image matched one of the previous pictures (half of these "test" images matched one of the previous pictures). The volunteers did 80 of these trials, 20 of each category. To help make sure they weren’t verbally memorizing what they were seeing, which might change the fMRI results, a radio news program ran continuously in the background during the task. Afterwards, the researchers analyzed the fMRI data, looking for which brain areas activated during the short delay between pictures (brain areas active in initial visual activity and encoding) and during the long delay (brain areas active during working memory).

Results

The fMRI data showed that the brain areas previously shown to activate during visualization, all located near the rear of the brain, declined in activity during the 10 second delay, although subtle differences between categories could still be extracted from the data. However, different areas near the front of the brain—specifically, the bilateral ventrolateral prefrontal cortex, dorsolateral prefrontal cortex and medial frontal gyrus—became active during the long delay. These areas activated without regard to what type of visual stimulus the volunteers saw, suggesting they activate in a more general pattern for visual working memory with no particular specialization based on image category.

Importance of the FindingsHumans have a remarkable ability to store visual information at high detail over short periods of time. During these storage periods, some of the brain activity seems to shift from visual areas in the rear of the brain to areas in the front that have been suggested to form part of the brain’s "control center." These areas do not appear to be specific for particular types of visual information. "We conclude that principles of cortical activation differ between encoding and maintenance of visual material," the authors say. Their findings provide support for current models that locate memory not in specific brain modules but in the concerted action of distributed networks in the brain.

Study Team

The study was conducted by David E. J. Linden of Cardiff University in Cardiff and Nikolaas N. Oosterhof, Paul E. Downing, and Christoph Klein, all of Bangor University in Bangor, United Kingdom.

NOTE TO EDITORS: The study is available online at http://bit.ly/wyY9eq. To request an interview with a member of the research team, please contact Donna Krupa at dkrupa@the-aps.org, @Phyziochick, or 301.634.7209.

Physiology is the study of how molecules, cells, tissues, and organs function in health and disease. Established in 1887, the American Physiological Society (APS) was the first US society in the biomedical sciences field. The Society represents more than 11,000 members and publishes 14 peer-reviewed journals with a worldwide readership.

 

Physiology is the study of how molecules, cells, tissues, and organs function in health and disease. Established in 1887, the American Physiological Society (APS) was the first US society in the biomedical sciences field. The Society represents more than 11,000 members and publishes 14 peer-reviewed journals with a worldwide readership.

 


Related Items

Research Model May One Day "Inoculate" Elderly Against Slip-Related Falls

Released February 4, 2009 - Training people to avoid falls by repeatedly exposing them to unstable situations in the laboratory helped them to later maintain their balance on a slippery floor, according to new research from the Journal of Neurophysiology.

Romantic Rejection Stimulates Key Brain Areas

Released July 6, 2010 -- The pain and anguish of rejection by a romantic partner may be the result of activity in parts of the brain associated with motivation, reward and addiction craving. A new research effort could explain why feelings related to romantic rejection can be hard to control and provide insight into extreme behaviors associated with rejection. Those who are coping with a romantic rejection may be fighting against a strong survival system that appears to be the basis of many addictions. The data help to explain why the beloved is so difficult to give up.

Have Brain Fatigue? A Bout of Exercise May be the Cure

Released September 16, 2011 - Researchers have discovered that regular exercise increases mitochondria in brain cells, a potential cause for exercise’s beneficial mental effects.

Is There a Central Brain Area for Hearing Melodies and Speech Cues?

Released November 28, 2011 - The perceptual feature of sound known as pitch is fundamental to human hearing, allowing us to enjoy the melodies and harmonies of music and recognize the inflection of speech. Previous studies have suggested that a particular hotspot in the brain might be responsible for perceiving pitch. However, auditory neuroscientists are still hotly debating whether this “pitch center” actually exists. A new review article discusses a recent study claiming that this pitch center may not exist after all, or alternatively, may not be located where previous research has suggested.

Researchers Block Damage to Fetal Brain Following Maternal Alcohol Consumption

Released August 11, 2008 - In a study on fetal alcohol syndrome, researchers were able to prevent the damage that alcohol causes to cells in a key area of the fetal brain by blocking acid sensitive potassium channels and preventing the acidic environment that alcohol produces. The cerebellum, the portion of the brain that is responsible for balance and muscle coordination, is particularly vulnerable to injury from alcohol during development.

From: 
Email:  
To: 
Email:  
Subject: 
Message:

~/Custom.Templates/PressRelease.aspx