As I looked into the history of the term, I began to suspect I might have fallen for a pseudoscientific idea. I learned that, while neuroscientists have shown that brain injury survivors sometimes struggle with certain tests of attentional and motor control, there’s little evidence linking this kind of ‘executive’ disinhibition with behavioural change – the social disinhibition I had been attributing to our clients. Instead, theories about this kind of disinhibition tend to rely on case studies.
I began researching the lives of two 19th-century figures who have both been described as disinhibited. The first was a railroad construction foreman, Phineas Gage. The second was the photographer Eadweard Muybridge (born Edward Muggeridge in England). The two were contemporaries, and both lived in San Francisco for a time. Both were injured in accidents. But there the similarities end. Despite Muybridge’s brain injury being well documented and despite it transforming him, as some claim, in profound and disastrous ways, he scarcely features in the brain science literature, and his legacy remains predominantly that of an artistic and technical genius. Gage, by contrast, became famous for the outrageous behaviour that supposedly resulted from his injury. The literature paints him as a kind of avatar for behavioural dysfunction, with every other aspect of his life overshadowed by his status as disinhibition’s patient zero. Why are the legacies of these two ‘disinhibited’ people so different? I believe the answer tells us almost everything we need to know about the condition, about its origins and its continued use today.
On the day of his accident in September 1848, Phineas Gage was working near the town of Cavendish in Vermont, using an iron ‘tamping rod’ to pack an explosive charge into a hole. The charge exploded prematurely, firing the iron straight through his head. Miraculously, Gage survived. He was transported, bloodied but conscious, to his hotel room, where a doctor called John Harlow cleaned and dressed his wounds. Gage convalesced for 73 days and then returned to his hometown in neighbouring New Hampshire. Harlow described Gage’s recovery as ‘without a parallel in the annals of surgery’, attributing it to Gage’s ‘physique, will, and capacity of endurance’ and to the ‘recuperative powers of nature’. But Harlow also noted a marked change in Gage’s personality: formerly a ‘favourite’ among his men and a ‘shrewd, smart business man’, Gage had become ‘fitful, irreverent, indulging at times in the grossest profanity.’ Gage was now ‘a child in his intellectual capacity’, Harlow continued, with ‘the animal passions of a strong man’. So changed was he, claimed Harlow, that friends and acquaintances said he was ‘no longer Gage’. The doctor concluded that this decline was a consequence of the damage done by the tamping iron to the frontal lobes of Gage’s brain.