Each day we process a wide variety of stimuli using our five senses: sight, smell, hearing, taste and touch. If we are bombarded with too many stimuli at once, our sensory organs are no longer able to process them and this can put us under psychological strain. This state is often referred to as sensory overload, and leads to stress, aggressive behaviour and rapid exhaustion. Researchers believe that modern life, and most particularly the all-pervading use of the internet and other new media, could induce chronic sensory overload, and cause people to experience difficulty in concentrating, disconnection with reality, hyperactivity, and even depression.
Researchers at the Max Planck Institute for Human Development and the Charité have conducted research to ascertain if and how frequent internet use affects the brain. So far, they have been able to show that people who use the internet extremely frequently, almost compulsively, have less grey matter in certain brain regions. Grey matter is the part of the central nervous system that is primarily made up of the neuronal cell bodies, as opposed to nerve fibres, which are the main component of white matter. Grey matter is mainly found in the outermost layers of the brain and covers the regions that deal with sensory perception, as well as muscle control, emotions and language.
Researchers have not yet been able to work out whether the differences in the amount of grey matter are the result of frequent internet use or a trigger for this kind of compulsive behaviour. Further studies are required to obtain an answer to this question.
Saskia Blank of the Ideas 2020 team answered this question in consultation with Simone Kühn, a neuroscientist at the Max Planck Institute for Human Development.