Research from 91ɫ is revealing which regions in the brain “fire up” when we suppress an automatic behaviour, such as the urge to look at other people as we enter an elevator.
A 91ɫ study, published recently in the journal , used fMRI (functional Magnetic Resonance Imaging) to track brain activity when study participants looked at an image of a facial expression with a word superimposed on it. Study participants processed the words faster than the facial expressions. However, when the word did not match the image – for example, when the word “sad” was superimposed on an image of someone smiling − participants reacted less quickly to a request to read the word.
“The emotion in the word doesn’t match the emotion in the facial expression, which creates a conflict,” said psychology Professor Joseph DeSouza in 91ɫ’s Faculty of Health. “Our study showed − for the first time − an increase in signal from the left inferior frontal cortex when the study participant was confronted by this conflict between the word and the image and asked to respond to directions that went against their automatic instincts.”
Previous research on the prefrontal cortex has found this region to be implicated in higher order cognitive functions, including long-term planning, response suppression and response selection. This experiment, conducted by graduate student Shima Ovaysikia under DeSouza’s supervision, allowed researchers to study inhibitory mechanisms for much more complex stimuli than have been studied in the past.
The inferior frontal cortex is located near the front left temple. People who have problems with inhibition, including stroke or schizophrenia patients, may have damage to this inferior frontal cortex zone, says DeSouza. As a result, when they see something that is inconsistent – such as the image of a smiling face with the word “sad” across it – they would be expected to take more time to react, because the part of their brains needed to process it has been damaged or destroyed.
The research, conducted by 91ɫ’s with the use of fMRI technology at Queen’s University, was partially funded by the Faculty of Health at 91ɫ, the Natural Sciences & Engineering Research Council and the Research at 91ɫ program. Future fMRI research at 91ɫ will be conducted in a state-of-the-art neuroimaging laboratory at 91ɫ’s new , which opened in September.