“The eyes are truly the window to our souls”

Maybe her eyes can tell us what she's thinking

The nature of consciousness has long been a fundamental question of human existence, and it's no surprise that scientists are employing scientific methods to improve our understanding of the subject.

For example, human beings are not "conscious" when they are asleep, so one criterion of consciousness is that a person must be aware of objects in the person's surroundings: [bold added]

[Researchers] used a combination of artificial intelligence, mathematics, and a close examination of the eye movements of individuals as they were shown images of people’s faces.

As it turns out, they found that important clues are revealed in the eyes. When people were shown clear images, their eye movements showed a distinct pattern that indicates they were aware of their surroundings. However, as the subjects were presented with progressively dimmer images of faces, the pattern of eye movement changed. Tracking these changes, [Yale Prof. Hal] Blumenfeld said, allowed researchers to discern whether the subjects actually perceived the face or not without asking them.

“The eyes are truly the window to our souls,” he said. “We can tell if people are aware of something by simply looking at their eyes.”

The eye-tracking tool allowed researchers to explore the amorphous dividing line between consciousness and unconsciousness, a state most obvious as we awake from sleep. People become progressively more aware of their surroundings as slumber recedes, a process that is controlled in a region of the brain known as the thalamus.

Ultrasound waves directed at the
thalamus can "jump start" coma
patients (Medindia)

The Yale researchers found that when people awake the thalamus discharges a brief pulse which jumpstarts the transition to consciousness. However, this activity is only a first step in a series of actions throughout the brain that leads to full awareness, they found. For instance, that initial pulse from the thalamus may fail to activate other neural networks, keeping the individual unconscious of most surrounding stimuli. However, the pulse can also activate neurons involved in processing visual cues in the frontal cortex, which in turn amplifies circuits involved in arousal and attention. At the same time, signals irrelevant to the event are turned off.

To those of us who have friends or relatives who regularly experience visual and/or auditory hallucinations, the research into consciousness and awareness can't proceed fast enough.

But for those like your humble blogger, whose brain is healthily grounded in reality (!) and is concerned about scientists being able to read thoughts through eye movements, wearing sunglasses is strongly recommended.