A new study conducted at the Belgium-based University of Liège’s ULiège GIGA Institute has unearthed insights into the influence of light on human cognition. The research utilized advanced 7 Tesla MRI imaging to provide an in-depth understanding of the brain’s response to different light intensities and qualities.

It’s common knowledge that light plays an integral role in regulating wakefulness, much like a cup of coffee. With the rampant use of smartphones and tablets, especially during nighttime, the excessive exposure to light can be detrimental to sleep. Conversely, the right type of light can boost alertness during daytime. This is primarily attributed to the blue part of the light spectrum, which is detected by receptors in people’s eyes and informs their brain about the surrounding light conditions.

Despite the known benefits and drawbacks of light exposure, the precise brain regions that process the ‘non-visual’ impact of light remained elusive. Ilenia Paparella, a doctoral student in the GIGA CRC IVI laboratory and the lead author of the study published in Communications Biology, clarifies, “The areas are minute and found in the subcortical part of the brain.”

With the superior resolution of the 7 Tesla MRI, the researchers were able to pinpoint that the thalamus, located just below the corpus callosum, plays a pivotal role in transmitting non-visual light information to the parietal cortex. This region is instrumental in regulating attention levels.

“While the thalamus’s significant contribution to vision was known, its involvement in non-visual aspects remained ambiguous. Our study confirms that the thalamus activates the parietal regions and not vice versa,” Paparella says.

The insights garnered from this research hold the promise of ushering in innovative lighting solutions tailored to either boost cognitive alertness or induce relaxation for a rejuvenating sleep, ULiège researchers say.