Bigger the Brain Smarter You Are? Scientists Have Found the Answer

Bigger the Brain Smarter You Are? Scientists Have Found the Answer

Group of neuroscientists at the University of Cambridge have predicted an “ideal” brain circuit size required to execute specific tasks. In a study published in PNAS journal, they explain how ‘neural circuits’ can utilize additional connectivity to attain faster & precise learning capacity.

As per the study, ‘redundant’ neurons – the cells responsible for our brain functionality along with synaptic connections – that coordinated the flow of information from one neuron to another, when added to a network becomes a double-edged sword. On the one hand, an increase in connectivity can make a task easier to learn. While On the other, because of inherent noisiness in signal-carrying connections, increased connectivity will eventually hinder both learning and task performance once a circuit exceeds a certain size.

The findings of this study suggest that the existence of a possibility – why excessive numbers of noisy connections can lead to learning disorders that are associated with brain hyperconnectivity, including some developmental forms of autism.

In a statement by Dr. Timothy O’Leary, Lead Author of the study who is a Lecturer in Information Engineering and Medical Neuroscience, “Our research shows that adding ‘spare’ or redundant connections to

brain circuits can, in fact, boost learning performance. These additional connections – which don’t appear strictly necessary for brain function – can make a new task easier to learn.”

“However, we found that if each new pathway adds ‘noise’ to the signal it transmits, the overall gain in learning performance will eventually be lost as a circuit increases in size. We can predict, therefore, that there is a so-called ‘sweet spot’, an ideal brain circuit size that suits a particular task. While evidence points to the fact that larger brains tend to be found in species with higher cognitive function and learning ability, brain circuit size may ultimately be constrained by the need to learn efficiently with unreliable synapses. In short, adding neurons and connections to a brain can help to learn – up to a point. After that, an increase in size could actually impair learning.” said Timothy.

As per reports, the research was funded by a European Research Council (ERC) grant FLEXNEURO (716643).

D. V. Raman; A. Perez Rotondo; T. O’Leary, ‘Fundamental bounds on learning performance in neural circuits’. PNAS (2019). DOI: 10.1073/pnas.1813416116 

This article has been adapted from the original post at the University of Cambridge.

Perfection is her hobby, Reliability is a synonym, Editing is her passion, Excellence is her Goal, Tactfulness is in her genes, Yellow is her Fav color. Preety is the name of the Professional on whom entire BioTecNika relies when it comes to its website. A Gold Medalist in Biotech from SRM University, Chennai with a 9.9 CGPA ( was awarded the Gold Medal by Honorable Prime Minister of India Shri Narendra Modi , as seen in the pic ), She decided to join forces with BioTecNika to ensure India's largest BioSciences Portal expands its reach to every city in India. She has redesigned the new avatar of BioTecNika from scratch and heads the most dynamic, vibrant and well informed Online Team at Biotecnika Info Labs Pvt Ltd