This post explores how eye movements relate to being a psychopath.
To cut to the point: eye movements relate to neural wiring ( white matter et al.) and so does psychopathy. So if there’s a problem with the white matter, it may be reflected in ocular motion.
Have you ever seen someone with truly shifty eyes? Their eyes go back and forth, sideways, jerkily? We’ve seen a psychopath in our orbit, in the throes of a fit of paranoia — claimed to be due to a waiter who was ignoring their table — rapidly shifting their eyes around while heatedly and loudly launching accusations against the poor waiter. We also saw it in a videotaped deposition of a witness in a business lawsuit, who was lying her eyeballs out, for lack of a better way to explain it. This witness had horribly unorganized documents and was, in our view, apparently set up to commit fraud on behalf of her boss. (Or maybe she volunteered — the money was pretty good.) There she was in the depo — and all the while her shifty eyes swished back and forth, jerkily. And that’s the thing: if you’ve ever seen this kind of jerky eye movement, you know there’s a problem.
We previously wondered if psychopaths have troubles detecting biological movement (as opposed to random or inanimate object movement): Who needs a professional body language reader? Those with faulty wiring for biological motion detection?
And there have been loads of reports that people with schizophrenia have trouble with “smooth pursuit” eye movement. Basically, where there is a smoothly moving target, your eyes should track it with similar smoothness. Schizophrenia impairs this smooth pursuit. And, where there is a hidden target that resumes along an inferred path, most people continue to have smooth pursuit — but not with schizophrenia. Plus, with schizophrenia, eyes track unexpected movement better than normals. (This has to do with synaptic firing, here. ). Schizophrenia impairs the ability to smoothly track predictable movement but enhances the ability to track unpredictable movement.
So we have, in schizophrenia at least, abnormal smooth pursuit of predictable movement (but better ability with unpredictably moving targets), and an impaired ability to detect biological movement — movement that can be predictable.
Does this mean that the white matter impairments in psychopathy also affect the ocular movements? And are psychopaths impaired in their ability to predict movement and detect biological movement?