United States: Attention deficit hyperactivity disorder (ADHD) traits such as distractibility or impulsivity are said to have an evolutionary advantage over our ancestors in terms such as they had developed better strategies for foraging as compared to those who did not have ADHD.
Prevalence of ADHD
ADHD is a neurodevelopmental disorder with symptoms including impulsivity, low inhibition, and difficulties in implementing the behavioral plan.
However, there are a lot of disparities in the prevalence statistics when the other countries have a rapidly growing rate of diagnosis, including the UK and the US, as the Guardian reported.
Why is ADHD disorder more frequent than expected?
Now, researchers hold views on what used to be regarded as disadvantages and have sharpened the minds of these people to hunt in new paths for food.
The first author of the study, dr. David Barack of the University of Pennsylvania argued that the research set down a possible reason why ADHD was occurring more frequently than expected based on the random occurrence of genetic mutations.
Therefore, this study might explain why individuals exhibit traits like distractibility and impulsivity with increased frequency.
As the Guardian reported, Dr. Barack said, “If [these traits] were truly negative, then you would think that over evolutionary time, they would be selected against,” and, “Our findings are an initial data point, suggestive of advantages in certain choice contexts.”
More about the research
Barak and fellow researchers demonstrated by examining the data from 457 adults who had completed a foraging game online they were required to gather as many berries as possible within eight minutes.
The count of berries was sequentially decreased with each bush with the number of times it was foraged.
In the described experiment, subjects had a possibility to either continue harvesting berries at the spot where they had found them initially or relocate up to a new bush – although the latter cost them time.
The members of the research team also screened participants for ADHD-like symptoms. Among the participants, 206 people had positive screens. However, the researchers state this does not mean that these individuals are actually diagnosed with ADHD, as the Guardian reported.
What did the researchers conclude during the research?
Researchers established that individuals with higher scores on the ADHD scale spent shorter times in the same patches of the bushes than those who recorded lower scores on the scale.
Thus, they became more persistent and were likely to leave their current site and look for something else. Importantly, the team gathered that such participants also gained higher scores in the game than those with lower scores on the ADHD scale.
The researchers said their conclusions showed consistency with other studies that pointed out the fact that the populations that lead a nomadic lifestyle benefited from traveling, which was linked to the genes associated with ADHD.
However, the authors had pointed out the study had limitations, one of them being that the hyperactivity- impulsivity symptoms were based on self-report.
Barack emphasized the need to involve people with diagnosed ADHD in hands-on experiments of real foraging tasks, especially since outdoor games would involve far more effort to travel between patches than a virtual game, as the Guardian reported.
What do the other scientists comment?
Michael J Reiss, a professor of science education at University College London who did not participate in this study, has indicated while ADHD appeared to be connected to serious negative effects, the role of this disorder might be beneficial under conditions where physical activity and rapid decision-making were highly valued.
He added, “It is great to see experimental evidence from David Barack and colleagues that participants who score highly for ADHD are more likely to switch their foraging activities in ways that can indeed be characterized as impulsive. In our evolutionary past, such behavior may sometimes have been highly advantageous,” as the Guardian reported.
He added further, “ADHD can be a serious problem, but it’s a problem in large measure because of today’s environments.”