Language performance and differences in brain activity possibly affected by sex

January 29, 2009

In a new fMRI study conducted in the Epidemiology, Biostatistics and Clinical Research Laboratory (Montpellier I University, France) and published by Elsevier in the February 2009 issue of Cortex, researchers found differences among male and female groups on activation strength linked to verbal fluency (words generation).

Results from previous fMRI studies identifying the neural basis of sex differences in language production are still in debate. Particularly, the question of group differences in verbal abilities which might account for neurocognitive differences elicited between men and women, still remain unresolved. Although the cerebral regions involved are identical for both men and women, men show greater activation than women, irrespective of performance levels in classical language regions (frontal, temporal and occipital lobes, and cerebellum).

From a representative sample of 331 French speakers, students showing a sex difference for a verbal fluency task, with women scoring higher than men as reported in the literature, four groups of 11 healthy right handed subjects were selected a priori. Selection was based on sex and contrasted scores in a fluency task i.e. high versus low verbal fluency scores. The 44 subjects were submitted to a covert verbal fluency fMRI protocol.

In addition to a sex effect, this design also shows a performance effect irrespective of sex. Low fluency subjects elicit greater activation in the anterior cingulate than high fluency subjects, with these later activating the cerebellum more than those with low performances.

The combined sex and performance effects play a role on activation strength. High fluency men differ both from low fluency men and high and low fluency women by showing more activation in the right precuneus and left dorsolateral prefrontal cortex and less activation in right inferior frontal gyrus. Furthermore, in low fluency women, the left anterior cingulate is activated more than in those with high fluency scores.

By dissociating sex and performance effects on brain regional activation strength, this study clearly shows either an effect exclusively related to sex in several regions, or another effect exclusively related to performance or indeed to the both in certain other regions.

Investigating the neural correlates of verbal fluency focusing on sex differences should take into account behavioral variations in order not to alter the conclusion and better grasp the complexity of the phenomenon being studied.

Journal: www.elsevier.com/locate/cortex>

Source: Elsevier

Explore further: Differences in language-related brain activity affected by sex?

Related Stories

Sex differences in brains reflect disease risks

June 26, 2007

Women’s brains are different from men’s. That’s not news. What is news is that the differences are smaller than most people believe. They are not big enough to say that one sex is smarter or better at math than the ...

Recommended for you

Machine Translates Thoughts into Speech in Real Time

December 21, 2009

(PhysOrg.com) -- By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The "thought-to-speech" process ...

Quantum Theory May Explain Wishful Thinking

April 14, 2009

(PhysOrg.com) -- Humans don’t always make the most rational decisions. As studies have shown, even when logic and reasoning point in one direction, sometimes we chose the opposite route, motivated by personal bias or simply ...

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.