Who Are You? Identity and Dementia

The Huffington Post:

Phineas Gage is arguably the most famous case study in the history of neuroscience. Gage was a railroad worker who in the autumn of 1848 was helping to prepare a new roadbed near Cavendish, Vermont, when an accidental explosion sent a three-foot tamping iron through his head. The missile entered the left side of his face, passed behind his left eye, and exited through the top of his skull. Gage, remarkably, lived to tell about the mishap.

But friends said he had changed — that he was “no longer Gage” — and this is what has intrigued psychological scientists. Formerly industrious and conscientious and amiable, he became irreverent and profane, incapable of returning to his former job. It appeared that the brain damage — primarily to his left frontal lobe — had dramatically altered his behavior and personality, the very essence of who he was.

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When they crunched all the data, the main finding was very clear: Identity disintegrates primarily when the moral system is impaired. Indeed, the primacy of morality, as a determinant of identity, held true even when moral impairment was not the dominant feature of the disease. Other cognitive deficits — including amnesia — showed no measurable impact on the persistence of identity. These results, reported in a forthcoming issue of the journal Psychological Science, speak to longstanding philosophical questions about the nature of identity, suggesting that moral capacity is more important than memory or emotional make-up the preservation of selfhood.

Read the whole story: The Huffington Post

Wray Herbert is an author and award-winning journalist who writes two popular blogs for APS, We’re Only Human and Full Frontal Psychology. Follow Wray on Twitter @wrayherbert.