Man missing 90% of his brain leads a normal life, scientists say

A 44-year-old man from France diagnosed with severe hydrocephalus reportedly had most of his skull filled with fluid and only a thin layer of brain tissue, yet lived with a family and worked; researchers say the case challenges some theories of consciousness and highlights extensive brain plasticity.

A 44-year-old man from France sought hospital care after weakness in a leg and was diagnosed with severe hydrocephalus. Imaging showed much of his skull occupied by fluid, leaving a thin layer of brain tissue. He lived with a family, had a job, and an IQ test at the time measured 84, slightly below the typical range. Researchers discussed the case, which was first described in The Lancet in 2007, at a recent conference on consciousness. Key facts: - The patient presented with leg weakness and was diagnosed with hydrocephalus. - Medical imaging reportedly showed most of the skull filled with cerebrospinal fluid and only a thin layer of brain tissue remaining. - The man was living a family and working at the time of his diagnosis; an IQ assessment was reported as 84. - The case was first described in The Lancet in 2007 and has been cited in scientific discussions since. - Axel Cleeremans and other researchers have said the case illustrates pervasive neural plasticity and poses challenges for theories that require specific neuroanatomical structures to explain consciousness. Summary: The case has been presented by researchers as evidence of extensive brain plasticity and as a challenge to theories that tie awareness to narrowly defined brain regions. Undetermined at this time.