As you read this, the neurons in your brain are creating a spectacular supernova of electrical impulses, connecting to each other in scandalously convoluted and ever-changing patterns. How this neural chaos translates into thoughts, insights, feelings, and awareness is something that even the greatest minds have failed to fathom, yet researchers from the University of Warwick may have now finally discovered the fundamental property underlying intelligence.
Reporting their findings in the journal Brain, the authors reveal how their research not only sheds light on the cerebral processes behind humans’ exceptional learning abilities, but could also help to explain the many mysteries behind mental illness.
In their write-up, the team note that until now, the majority of studies into the roots of consciousness have tended to look at either the overall activity of the brain when performing certain tasks or specific individual connections between two chosen brain regions. However, no one has yet investigated what the researchers call the “temporal variability of the functional architecture” of the brain.
In more basic terms, this refers to the amount by which the patterns of communication between a particular brain region and all other regions changes over time, thereby giving an indication of how static or flexible the connectivity of that region is. This is thought to be important since a number of studies have previously shown that brains that are more flexible tend to belong to more intelligent people, with a greater IQ and capacity to learn novel tasks.
To conduct their investigation, the study authors collected functional magnetic resonance imaging (fMRI) and electroencephalogram (EEG) data from 1,180 people across the world. After analyzing this information, they noted that brain areas that are heavily involved in learning – such as the hippocampus, olfactory gyrus, and caudate – all show high temporal variability, meaning they regularly and rapidly change their patterns of connectivity.
In contrast, brain regions that control more automatic functions that aren’t related to consciousness, such as the sensory-motor cortices, display low temporal variability, maintaining a much more static pattern of connectivity.
Image: The degree by which a brain region's connectivity varies over time is a key indicator of its capacity to learn. XStudio3D/Shutterstock
Extrapolating from this finding, the researchers explain that flexibility may be the key property that enables particular brain regions to learn and develop, suggesting that this temporal variability could well be the main facilitator of intelligence.
As well as implying that the outcomes of this study could be used to improve artificial intelligence by developing new artificial neural networks that are capable of learning, the authors also believe their work will have major implications for the study of mental illness.
To prove this, they included a number of people with certain cognitive disorders in their study, showing how these individuals all had highly abnormal temporal variability in certain brain regions when compared to healthy people.
For instance, those with schizophrenia were found to have extremely low variability in a brain network called the default mode network (DMN), which is largely responsible for self-awareness, and especially high variability in a region called the thalamus, which is also heavily implicated in consciousness.
At the other end of the scale, people with autism and attention deficit hyperactivity disorder (ADHD) had abnormally high temporal variability in the DMN and low variability in the thalamus.
Though the human brain is famous for refusing to give up its secrets cheaply, and is likely to go on frustrating even the most gifted neuroscientists for many years to come, this study could prove to be a turning point in our quest to finally understand what consciousness is. (Or it could not…)
Image: Consciousness - it's bloody complicated. agsandrew/Shutterstock
