A recent study on emotional response—Amygdala Responsivity to High-Level Social Information from Unseen Faces—indicates that the Buddha’s five skandha explanation of consciousness has it right.
From the study’s abstract:
The findings demonstrate that the amygdala can be influenced by even high-level facial information before that information is consciously perceived, suggesting that the amygdala’s processing of social cues in the absence of awareness may be more extensive than previously described.
Note that all important phrase “…before that information is consciously perceived.”
The five skandhas are form, sensation, perception, activity, consciousness. A form can arise in the mind or outside of the mind. This form gives rise to a sensation, which gives rise to perception, followed by activity (mental or physical), and lastly consciousness. In the Buddha’s explanation, the five skandhas occur one after the other, very rapidly. They are not a continuous stream but rather a series of discrete or discernible moments. A form arises or appears, then there is a sensation, then perception, then activity, then consciousness.
Advanced training in meditation and mindfulness is probably necessary for most people to be able to observe the five skandhas individually, as they are actually “firing,” but it can be done. A good deal of Buddhist practice is based on being able to do that.
Though all brain imaging studies must be taken as provisional since the technology is not completely reliable, they still are providing us with some very interesting information worth considering.
The amygdala study cited above seems to confirm that people form significant emotional reactions to faces without being conscious of their reactions at all. In Buddhist terms, their reactions are (or take place at) the second skandha—sensation.
The skandha of sensation is defined as a reaction to a form that is either positive, negative, or neutral. That is, we either like, dislike, or don’t care about the form. In the amygdala study the form is the face that is flashed very briefly on a screen. The face appears so briefly, for just a few milliseconds, that it is not possible to actually “see” or be aware of having “seen” it.
I think it is fair to extrapolate from this study that we humans are forming sensations all the time without being aware of what we are doing. As the authors of the study say, the study “[suggests] that the amygdala’s processing of social cues in the absence of awareness may be more extensive than previously described.”
“…processing of social cues in the absence of awareness” is pretty good description of what the Buddha called delusion, especially if we realize that the delusions we “process” from forms arising outside of us are entwined with and not very different from delusions we process from forms arising within us.
The Buddha’s five skandha explanation, thus, provides a way to observe and analyze our minds to prevent our becoming deluded by the tug of sensations that happen in the “absence of awareness.”
A few days ago, I reposted an essay that touches on this subject from a different angle and a different study: we do not sample our world continuously but in discrete snapshots.
Here is a pretty good article on the study cited above: Friend Or Foe? Even When Faces Are Not Clearly Visible, Your Brain Unconsciously Makes Judgments.