Our Brains on Psychopathy
We have heard about the deficit in the connection between the amygdala and the pre-frontal cortex which helps explain psychopathy. But this is something else. This article (There’s Now More Evidence Linking Psychopathy to Disturbances in The Prefrontal Cortex by Fiona MacDonald) talks about the greater density in the pre-frontal cortex of psychopaths and, get this. There is a greater connectivity between two areas of the pre-frontal cortex, called the superior frontal gyrus and the inferior frontal gyrus. I looked up the properties of each of these “frontal gyruses.” The “inferior” one has primarily to do with language. The “superior” one is about self-awareness and laughter. Interesting combination. I guess when we become really self-aware, we just have to laugh.
Here’s an excerpt about the Superior one:
In 1998, neurosurgeon Itzhak Fried described a 16-year-old female patient (referred to as “patient AK”) who laughed when her SFG was stimulated with electric current during treatment for epilepsy. Electrical stimulation was applied to the cortical surface of AK’s left frontal lobe while an attempt was made to locate the focus of her epileptic seizures (which were never accompanied by laughter).
Fried identified a 2 cm by 2 cm area on the left SFG where stimulation produced laughter consistently (over several trials). AK reported that the laughter was accompanied by a sensation of merriment or mirth. AK gave a different explanation for the laughter each time, attributing it to an (unfunny) external stimulus. Thus, laughter was attributed to the picture she was asked to name (saying “the horse is funny”), or to the sentence she was asked to read, or to persons present in the room (“you guys are just so funny… standing around”).
Increasing the level of stimulation current increased the duration and intensity of laughter. For example, at low currents only a smile was present, while at higher currents a louder, contagious laughter was induced. The laughter was also accompanied by the stopping of all activities involving speech or hand movements.
Well, you can read all of this by clicking on the links. I want to move on to the question of how greater density and extra connectivity between such interesting parts of the brain adds up to a “disturbance.” Maybe it’s just a disturbance by definition if it is found in the brain or personality of a psychopath. I wonder how these scientists think connecting these two area leads to psychopathy. Maybe self-aware amusement gets together with lingual ability to make us glib and cunning. That would go together. Awareness, laughter and language working together to make one tricky psychopath.