The Curious Thing About Curiosity
We exasperate our parents with an endless series of WHYs beginning around two years of age. Non-human animals do not appear to have a need to wonder why things are as they are. Studies put Chimpanzees’ intelligence between that of a 2 - 5-year-old human depending on the study.
But chimpanzees show no evidence of wondering why something occurs; they lack a curiosity about cause and effect and focus only on the “what” or “how”. A chimp witnesses an older chimp retrieving termites from a hole in the ground with a stick and mimics the behavior but doesn’t consider why it works.
By contrast, children quickly understand that effects are inextricably linked to causes. A child is disciplined and mentally replays the events leading up to the punishment to understand what caused the unpleasant consequence. Or a child may crawl around wondering what it would be like to be a puppy. Human curiosity reaches beyond that necessary to effectively function in the environment.
The answer is found by studying the subject of curiosity. The academic research into curiosity is surprisingly complicated and requires extensive brain imaging, cognitive experiments, and an understanding of the effect of chemical processes on human behavior. I will skip the technical details and risk oversimplifying the answer by summarizing the two pertinent categories of curiosity at issue. Epistemic curiosity (EC) is motivated by the sheer enjoyment of exploring new physical and mental territories. Perceptual curiosity (PC) motivates us to avoid distress and potential harm that threatens our ability to survive and reproduce. Humans experience both types of curiosity while non-human animals experience only PC. It is EC that compels us to ask why and to explore abstract ideas, engage in creative endeavors, and undertake scientific research. Unlike, PC, we pursue EC as a rewarding activity. Some researchers claim it is an essential component of our survival as a species, like eating and sex.
When we are startled by an unexpected threat or an unresolved ambiguity, we are driven to learn to recognize under what circumstances we might again encounter such an event. If a food source causes illness or an unpleasant sensation animals including humans avoid it in the future. Curiosity causes animals to identify predictors of distress and punishments, or alert them to unexpected things that might be harmful, or are not understood. Evolution has weeded out creatures that lack PC so it is no surprise that all cognizant animals have some variant of it.
|Functional MRI (fMRI)|
Studies using fMRI with humans reveals that when something puzzling happens, when danger suddenly appears, or when there is sudden unresolved ambiguity, different portions of the brain become active in sequence. First, the incident activates portions of the brain that react to conflict and provokes intense awareness. Next as surprise and confusion resolve, there is a sense of relief and the reward processing part of the brain activates. Finally, a portion of the brain locks in memory of the event.
The PC response increases the likelihood that the individual, and therefore the species, can survive and reproduce. While lower forms of life (worms, insects, reptiles, etc.) don’t have brains organized in the same manner as humans, they do have mechanisms that cause the organism to avoid fatalities. Indeed, successful evolution could not have occurred without it.
Derived from the word epistemology (the theory of knowledge), epistemic curiosity (EC) engages different portions of the human brain driving humans to understand cause and effect, and to explore the unknown. In short, this is the source of humans’ thirst for knowledge. We can thank EC for our understanding of science, our appreciation of the arts, the present state of technology, the satisfaction we get from exploring all the “whys” we encounter throughout our lives (this explains why I muse about the random array of subjects that make up this blog and the much larger list subjects that don’t get posted).
The technologies that allow exploration of chemical and brain activities (fMRI, tracing chemical activity in our bodies, cleverly designed cognitive experiments, etc.) reveal how EC differs from PC and why it is unique to humans.
Unlike PC, EC reaches beyond information required for survival and reproduction. We each accumulate knowledge in particular areas of interest. When we find gaps or disparities in our knowledge, we are compelled to learn more, not because we are distressed by ambiguity, but because we anticipate an emotional and psychological reward from filling the void. As you might guess, the parts of the brain that respond to rewards are quite different than those that respond to distress. In particular, dopamine is released by certain neurons to facilitate transmitting signals to other neurons. Specific dopamine pathways specialize in motivating reward oriented behavior. Dopamine drives EC.
Why Is EC Uniquely Human?
Humans differ from non-human animals in several ways that likely account for the evolution of EC: 1) We have many more neurons in the cerebral cortex (three times that of an orangutan, for example); 2) Human neurons are much more compact than in other species because we need to carry them around while walking upright; 3) We use much more energy to power our brains than do other animals. These physiological advantages give us more powerful and more effective information processors that are capable of engaging in EC.
Scientists speculate that these unique characteristics have evolutionary roots.
● There is a physiological trade-off between a large body and a large brain; we can’t have both for many reasons (e.g., efficiently walking upright requires a slim torso that cannot safely give birth to an infant with a large head). Thus we had to seek food sources that have high caloric efficiency. EC motivated us to explore a variety of food sources in a variety of locations.
● A diet rich in meat has high energy content; cooking with fire reduced calories spent chewing; shortened intestines increased the efficiency of digestion.
● Walking upright reduced the energy needed to acquire food compared to moving about using knees and knuckles.
● Our EC likely was enhanced by the rewards of exploring new food sources, opportunistic uses of tools by walking upright, imagining shelters where there were no caves, traveling longer distances using fewer calories by walking uptight.
Whether EC eventually will be a curse or a blessing remains to be seen. Perhaps we should frequently remind ourselves to devote more time imagining and creating a more peaceful world -- let us hope nature’s course is not beyond the authority invested in its most advanced creatures.
Word of the day: teleology
The word teleology has two Greek roots, telos (purpose) and logos (explanation). As the roots of the word imply, teleology explains phenomena in terms of ends rather than means or causes. For example, rather than explain the world as a purposeless collection of phenomena randomly caused by the laws of physics, teleology would explain things as a cohesive system having a purpose-designed by an omnipotent intelligence, or) as an inevitable progression from a “Big Bang” towards a “Big Freeze” or a “Big Crunch”, or as simply an orchestra of living creatures whose destiny is governed by the laws of nature with no other objective than to harmonize and hopefully enjoy the performance.