The Science Behind Right-Handedness And Left-Eyed Bias In Humans

Scientists have found that, similar to animals, humans also have behavioural biases that are not unique to our species. A new study published in the journal Scientific Reports suggests that aligning these biases with others may have social benefits.

As per the report titled "Motor-sensory biases are associated with cognitive and social abilities in humans," one such bias is the visual field bias, where a significant portion of the population is faster and more accurate at recognising things thought to develop in early childhood. identities and emotions on one side of their visual field compared to the other. This bias is thought to develop in early childhood.

Research on animals shows that having a bias is not only common but also beneficial. Chicks that peck with an eye bias are better at telling food from pebbles, and those that monitor predators with a specific eye are less likely to be eaten.

The study suggests that biases free up brain resources, making animals more efficient at survival tasks. Interestingly, the study found that it's the presence of a bias, not the direction (left or right), that matters for performance.

However, why do many people have a right hand bias for motor tasks and a left visual field bias for face processing? The study suggests that this alignment with the majority might have social advantages. Animals that align with the group during cooperative behaviour are less likely to be singled out by predators.

The study also found that people with a standard bias (right-handedness for motor tasks, left visual field bias for face processing) were not necessarily better socially compared to those with a non-standard bias. However, those with a reversed bias (left handedness for motor tasks, right visual field bias for face processing) were more likely to have social difficulties and diagnoses of autism or ADHD.

While the study doesn't establish a causal relationship between the reversed bias and autism or ADHD, it paves the way for further research to investigate if bias profiles can be used as early markers for these conditions.