Thinking too hard can be bad for brain
Mentally taxing tasks really can do your head in – by damaging nerve cells.
But the process is normal and the damage quickly repaired in healthy brains, a study at the Gladstone Institute of Neurological Disease in San Francisco, found.
The problem arises when the brain is not healthy. In that case the repairs are not made fast enough, leading to illnesses such as Alzheimer's.
Scientists working with mice found that stimulation disrupted DNA in their neurons. The particular type of damage, called a double-strand break, or DSB, has long been suspected of driving age-related illnesses such as Alzheimer's.
The researchers found that DSBs were a normal part of learning.
"This damage-and-repair pattern might help the animals learn by facilitating rapid changes in the conversion of neuronal DNA into proteins involved in forming memories," said Dr Elsa Suberbielle.