After a fair amount of googling, I finally tracked down Nardi's "This is Your Brain on Type" slides.
First, I can't help but point out that his sample size is very small (he only had one or two people for many types, and lacked an ISTP), and he doesn't go over any statistical analysis he did to show how strong the type-related effects were. He also doesn't describe how people were selected, so self-selection is likely an issue. Anyone looking for solid statistical data is going to be disappointed.
On the other hand, the data he did collect are pretty thought provoking. His general approach was to attach an EEG to people of various types, and collected data on the activity level on various regions of the brain.
Some of his interpretations of his data:
- Fe's responded the most to social feedback in T5
- INFPs and ENFPs, followed by INFJs and had had high activity in F8 when assessing emotional importance. For their ENTJ, F8 was only active for negative judgements.
- ESTJs and ENTJs were the best liars
- ENFPs followed by INFPs had the most active "mirror neurons," followed by INFJs
- INFPs fully mentally engaged when listening to others give instructions, offer reasons, etc. Their brains resembled those of experts engaged in their areas of expertise.
- One way to disengage an "expert listener" INFP is to have him or her discuss gun control with an ESTJ for 8 minutes.
- Te-doms and Ti-doms were more "mentally efficient." That is, there brains were minimally activated much of the time, unless interesting analysis was called for.
Based on mappings to brain regions, here he how would define the functions (from his slide "Clarifying Jung's Functions"):
- Ne: Transcontextual thinking (linking contexts), analogizing, mirror others, mental what-if simulation.
- Ni: Project into future, draw upon entire mind to foresee or determine an answer, weight many factors at once.
- Fi: What is of personal value to oneself, listening with the whole mind, tone of voice.
- Fe: Attend to how other people are responding to you, social appropriateness, attend to words.
- Te: Decision-making, explanation, construct visual images, minimal / optimized use of brain (when dominant function), fabricate / lie.
- Ti: Define, categorize, derive solution logically, minimal / optimized use of brain (when dominant function).
- Se: Recall details of recent data with high fidelity, identify objects, smooth body motion, calm in tense situations.
- Si: Access narrative past, use whole mind to review past events, other... (need more data!)
So, I hope there's more to come from Nardi in this area.