"Subjective reports from the subject indicated extremely high magnitude of reward, comparing [1st jhana] (which was not recorded due to head movement) to continuous multiple orgasms."
"Case Study of Ecstatic Meditation: fMRI and EEG Evidence of Self-Stimulating a Reward System" appears to be some kind of rehashing of data from a study that actually launched this blog (EEG of Jhanas) and is based on data collected from Leigh Brasington. In the article, the following hypotheses were substantially confirmed:
H1: Jhanas should show decreased activation compared to the rest state in the visual (BA 17–19) and auditory (BA 41-42) processing areas. Since all jhanas share the experiential characteristic that external awareness dims, then the brain regions associated with vision and hearing should become less active.We really need some sample size here. The pragmatic dharma community could supply a few subjects.
H2: Jhanas should show decreased activation compared to the rest state in Broca’s area (BA 44,45) and in Wernicke’s area (BA 39,40). Because internal verbalization fades in jhana, the brain regions associated with speech should become idle or less active.
H3: Jhanas should show decreased activation compared to the rest state in the orientation area (BA5). Since the normal sense of personal boundaries is altered, the orientation area of the brain should show changes from normal rest. Newberg and Iversen  showed that monks and nuns experiencing “union with God” exhibit decreased activation in this area.
H4: Jhanas should show increased activation compared to the rest state in the Anterior Cingulate Cortex (ACC) (BA 32,33). Because attention is highly focused on the object of meditation in the jhanas, we would expect high activity in the ACC, which regulates and monitors attention.
H5: Jhanas should show increased activation compared to the rest state in the dopamine reward system of the brain (NAc in the ventral striatum and medial OFC). A broad range of external rewards stimulate this system (food, sex, beautiful music, and monetary awards), so extreme joy in jhana may be triggered by the same system (the VTA is also part of this system, but is too small to image with standard fMRI methods, but see  for successful imaging methods).
H6: Jhanas should show no increased activation compared to the rest state in the areas responsible for rhythmic movement, including motor cortex (BA4), primary somatosensory cortex (BA 1,2,3), and cerebellum. Increased activity in these areas would support an alternative hypothesis that the reward system is being stimulated not by internal means but by subtle rhythmic movements that are known to induce ecstatic states .