The patient "M. S." was a previously healthy 29 year old Israeli graduate student who suffered injuries in a terrorist attack. As the MRI scans above show, she lost large parts of her orbitofrontal cortex and ventromedial prefrontal cortex, although the left side was only partially affected. She also lost her right eye.These areas are known to be involved in emotion and decision making. Her lesions are somewhat similar to those suffered by the famous Phineas Gage, and as we'll see, her symptoms were too - but only temporarily.
One year after the injury...
M.S.’s complaints included a sense of general fatigue, loss of taste and smell, difficulty concentrating and emotional changes including irritability, lability, depression and social isolation. She reported failing to make new social contacts, having lost most of her old friends, and a diminished need for social relationships.These personality and mood changes are reminisicent of those Phineas Gage suffered. Strangely, she scored 33 on the self-report depression scale the BDI, which corresponds to "severe depression", but from the description she doesn't sound depressed in the normal sense. These scales were not designed for people with brain lesions. Her cognitive function and memory was mostly normal but with clear impairments on some tests.
M.S. reported that family and friends commented on her change from a quiet and pleasant person to a rude, annoying, uninhibited, and unstoppable talkative person following the injury... M.S. had become apathetic, without a sense of time, and with no plans for the future.
On examination, M.S. was fully cooperative. She had difficulty concentrating and required frequent breaks. She appeared euphoric, laughed frequently and inappropriately, talked too much,made inappropriate remarks and jokes, yawned loudly... M.S. found it difficult to sit still and showed utilization behavior, continuously fidgeting and touching objects on the table. She had a tendency to continue performing tasks after completion was stated.
Anyway, that was after 1 year, and if that were the end it would be a rather sad story, but there's a happy ending. After this she got psychotherapy and rehabilitation treatment. 7 years later she had a follow-up assessment and she was much improved.
Her mood, attention-span and so forth were reported as normal. She struggled with her graduate studies, finding them more difficult than before the injury, and had eventually quit them, but she'd got a new job. She had recently got married.
Her performance on neuropsychological tests designed to measure prefrontal cortex damage was mostly normal, and she did much better on the ones that she used to be impaired on. She still did poorly on the Iowa Gambling Task, which is very sensitive vmPFC damage.
Overall, though, she had made a "magnificent" recovery despite losing a large chunk of her brain. I've previously been skeptical of some of the stronger claims of neuroplasticity or "brain remodelling", but some parts of the brain are more plastic than others and the prefrontal cortex seems to be one of the most flexible.
Fisher T, Shamay-Tsoory SG, Eran A, & Aharon-Peretz J (2011). Characterization of recovery and neuropsychological consequences of orbitofrontal lesion: A case study. Neurocase, 17 (3), 285-93 PMID: 21667397
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