People with neurodevelopmental disorders, such as autism or ADHD, can suffer acutely from sensory overload and it can involve any of the five senses. Anyone can suffer from sensory overload because it is when someone feels overwhelmed from stimulation around them. Intense emotions tend to excite sensory overload since people tend to be more aware, especially when emotions like fear heightened people’s senses. When a person feels sensory overload, they go into fight, flight, or freeze so that they react without thinking. People who do not suffer from a neurodevelopmental disorder can habituate themselves to situations so that they do not experience sensory overload as often. Habituation occurs when a sensation is experienced often enough that a person stops noticing it. The most obvious example is how your sense of touch quickly acclimates to your clothing. Within a minute of getting dressed, you no longer pay attention to the way your clothes feel against your body. Your brain stops paying attention to the sensation because it isn’t relevant information about the surrounding world. People who are considered neurodivergent have lower experiences of habitation, but why this occurs is less well understood.
A recent study from the Council of Scientific and Industrial Research located in Hyderabad, India, tried to understand what causes the decreased habituation. Initial research indicates that there is a transporter protein that likely works to help a person habituate to the world around them. They studied fruit flies with a particular scent, and found that the choline transporter played an important role during the process of habituation. Choline is considered a nutrient that affects liver and nervous system functionality and in the way a brain develops. It was found to help the brain become more flexible for habituation. When choline is transported to the brain, the brain begins creating acetylcholine, which is a neurotransmitter. It is the increase in acetylcholine that allows for habituation. The fruit flies that had less choline did not habituate as quickly, leading to hypersensitivity.
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