You gaze upwards into the azure sky and spot something indiscernible. Could it be a balloon? An aircraft? A UFO? Your curiosity is piqued, isn’t it?
A team of researchers at Columbia’s Zuckerman Institute has for the first time observed the brain activity associated with the emergence of curiosity in situations like this. In a report released in the Journal of Neuroscience, the researchers identified cerebral regions that evaluate the level of uncertainty in visually puzzling scenarios, leading to subjective curiosity.
“Curiosity has deep biological roots,” specified corresponding author Jacqueline Gottlieb, PhD, a lead researcher at the Zuckerman Institute. She noted that curiosity’s primary evolutionary purpose is to prompt organisms to explore their environment in ways that boost their chances of survival.
Dr. Gottlieb, also a neuroscience professor at Columbia’s Vagelos College of Physicians and Surgeons, explained: “Human curiosity distinguishes itself by driving us to explore much more extensively than other creatures, often purely driven by a desire for knowledge instead of aiming for a material gain or survival advantage. This inclination contributes significantly to our creativity.”
Accompanying Dr. Gottlieb on this endeavor were Michael Cohanpour, PhD, a former Columbia graduate student (now a data scientist at dsm-firmenich), and Mariam Aly, PhD, previously at Columbia and presently an acting associate professor of psychology at the University of California, Berkeley.
Utilizing a common, non-invasive technology to gauge variations in blood-oxygen levels in the brains of 32 volunteers, the researchers delved into functional magnetic resonance imaging (fMRI). This imaging method enabled the team to monitor the oxygen consumption in different cerebral regions as participants viewed images. Higher oxygen consumption indicated increased brain activity.
To pinpoint the cerebral areas implicated in curiosity, the team presented volunteers with texforms, specialized distorted images of objects like a walrus, frog, tank, or hat. Subjects were asked to rate their uncertainty and curiosity levels for each texform. The researchers discovered an inverse relationship between the certainty and curiosity levels. The more convinced participants were about identifying the texform, the less curious they felt. Conversely, higher curiosity correlated with lower confidence in recognizing the texform.
Cerebral Activity and Curiosity
Using fMRI, the researchers monitored cerebral activity while participants viewed texforms. The brain-scan results displayed heightened activity in the occipitotemporal cortex (OTC), a sector near the ears long associated with vision and object categorization. Building on prior research, the team anticipated that clear images would elicit distinctive activity patterns in this brain region for animate and inanimate objects. Dr. Gottlieb likened these patterns to ‘barcodes’ denoting texform categories.
These patterns were then utilized to formulate an ‘OTC uncertainty’ metric, reflecting the uncertainty in this cortical region about a distorted texform’s category. The researchers observed that lower curiosity levels were linked to a single barcode within the OTC activity, indicating clear identification of the texform’s animate or inanimate nature when subjects were less intrigued.
On the contrary, when participants were more inquisitive, their OTC exhibited qualities reminiscent of barcodes, almost as if it couldn’t precisely discern the image category.
During the texform displays, two regions at the front of the brain were also active. One being the frontal cingulate cortex, which past research has linked to information acquisition. The other is the ventromedial prefrontal cortex (vmPFC), which plays a role in monitoring an individual’s personal assessments of importance and certainty in varied situations. In the recent study, both regions displayed heightened activity when participants expressed heightened assurance in recognizing a texform’s identity (thus, being less eager to view the clarified image).
Significantly, according to Dr. Gottlieb, the activity in the vmPFC seemed to act as a neural connection between the subjective sensation of curiosity and the OTC certainty measurement. It’s as if this area interpreted the uncertainty embedded in the dispersed activity pattern in the OTC and assisted in determining if one needed to be curious about the texform.
“This marks the primary instance where we can correlate the subjective feeling of curiosity toward information with the way the brain represents that information,” Dr. Gottlieb pointed out.
Dr. Gottlieb highlighted two crucial implications of the study. Firstly, although the study emphasized perceptual curiosity provoked by visual stimuli, individuals encounter other varieties of curiosity, such as being curious about trivial queries and factual aspects (e.g., the height of the Eiffel tower) or social curiosity (like which restaurant their friends visited last night). She pointed out that one fascinating prospect of the study is that the mechanism it unveiled might extend to other forms of curiosity. For instance, an fMRI examination exploring sounds of varying recognizability could indicate that auditory sections of the brain communicate the uncertainty surrounding the sound, with the vmPFC decoding this uncertainty to gauge curiosity.
A second thought occupying Dr. Gottlieb’s mind is that these findings might have diagnostic and potential therapeutic implications for individuals dealing with depression, apathy, or anhedonia (the incapacity to experience joy), conditions often characterized by a lack of curiosity.
“Curiosity embodies a form of eagerness, a readiness to exert effort and explore one’s surroundings. It’s inherently driven, meaning no one is rewarding you to be curious; rather, you’re curious simply because of the expectation that learning something valuable will ensue,” remarked Dr. Gottlieb. “Those are merely a few of the remarkable aspects of curiosity.”
Reference: “Neural Representations of Sensory Uncertainty and Confidence are Associated with Perceptual Curiosity” by Michael Cohanpour, Mariam Aly and Jacqueline Gottlieb, 4 July 2024, Journal of Neuroscience.
Image Source: Lia Koltyrina / Shutterstock
