Radiolab Presents: Invisibilia

The episode explores 'alternating gender incongruity,' a phenomenon where individuals experience abrupt, involuntary shifts between male and female gender states, affecting perception, behavior, and cognitive performance. It presents preliminary findings from researcher Laura Case, who observed differences in spatial and language test performance based on gender state. The condition remains unclassified, with no definitive biological or psychological explanation yet established.

It introduces a rare, poorly understood human experience with early scientific inquiry suggesting real neurocognitive shifts across gender states.

1. 01Some individuals experience involuntary, rapid shifts between male and female gender states, known as alternating gender incongruity.
2. 02Preliminary tests show cognitive performance (e.g., spatial reasoning, language) varies with gender state in these individuals.
3. 03No diagnosis or mechanism is confirmed; the phenomenon may be neurological, hormonal, or conceptual, not psychiatric.