New research from American scientists provides deeper insight into what happens inside the brain when we don’t get enough sleep. Their findings suggest that sleep deprivation doesn’t just make us feel tired—it actually leaves individual nerve cells too fatigued to function properly.
Most people are familiar with the mental fog that follows a poor night’s sleep: slower reactions, reduced focus, and difficulty processing information. Now, researchers have been able to observe the neurological basis for these effects with unprecedented precision.
An international research team studied how neurons respond when people are deprived of sleep. They found that the responsiveness of individual nerve cells dropped significantly after participants stayed awake for an entire night.
The study involved 12 patients undergoing treatment for epilepsy at the University of California. As part of their clinical care, electrodes had already been implanted in their brains to locate the origin of seizures. This setup gave scientists a rare opportunity to record activity from individual neurons in real time.
The researchers discovered that sleep deprivation impaired the neurons’ ability to encode information and convert visual input into conscious thought. Slower brain-wave patterns were also detected, particularly in the temporal lobe and other cognition-related regions.
Previously, scientists believed that insufficient sleep caused a general slowdown across neural networks. This study, however, shows that the problem occurs at the cellular level: individual neurons begin to “lapse,” losing their capacity to communicate efficiently.
As a result, nerve cells react more slowly to incoming sensory information, contributing to delayed responses and lapses in attention. Such impairments can have real-world consequences—for example, increasing the risk of accidents when driving or operating machinery.
The findings were published in the journal Nature Medicine.
Reference:
Nir et al., Selective neuronal lapses precede human cognitive lapses following sleep deprivation, Nature Medicine, November 6, 2017. DOI: 10.1038/nm.4433.