Jun 7, 2021
Humans are often considered very (if not the most) curious-driven creatures yet it’s surprising that we know very little about curiosity itself. Humans often link curiosity with intelligence, but curiosity may also be defined as “novelty seeking behavior” or an inclination to explore. One could say Eve’s motivation when she bit the apple was that she was curious. When Isaac Newton sat under an apple tree, the rude awakening of an apple falling on his head sparked his theory of gravity. Curiosity has sparked invention and shaped our world, and we know almost nothing about the nature of a curious nature.
Curiosity can be an abstract idea but a new study with mice makes an elusive trait more tangible. By studying “curiosity” as an animal desire, new research suggests that curiosity is a driver and a want to satiate curiosity is a motivator by its own means. Or, mice were shown to be curious… just for curiosity’s sake!
Challenges Studying A Curiosity Trait:
New research exploring curiosity in animals is a significant breakthrough partly because of how little we currently understand about it. In mice, this study shows a correlation between a loop of neurons activating in the brain and investigatory behavior.
The part of the brain that seems heavily involved in the curiosity process is the Zona Incerta. The Zona Incerta is located deep in the center of the brain, making it difficult to access with today’s brain scan technology
Curiosity is thought to be “braided into” the same neuron cells’ feedback loop that relates to Hunting and Feeding actions. It has been especially difficult to isolate behavior that is solely “curious” for it’s own sake and not predatory or food motivated
Due to the nature of how neurons activate it’s extremely challenging to pinpoint how neurons are responsible for an animal’s behavior, actions, and motivation
Neurons activating or de-activating is not predicative of behavioral action
Animal motivation is extremely difficult to quantify. Translating a vague trait like curiosity into objective measures is tricky. What is the link between expressing curiosity and action taken? How does one express curiosity?
Breakthroughs in Understanding Curious Behavior:
Established Neurological Link:
Some (but not many) studies have successfully examined curiosity as an animal behavior. These studies have been focused on just observing behavior without a neurological link. Curious behavior in animals looks like approaching an object, sniffing, “whiskering”, touching, and carrying. When two dogs cross paths, they are curious in who the other dog is. A cat might knock over a vase just out of curiosity. But until now there’s never been a neural pathway or circuit connected to these curious actions.
Active Neurons Correlated to Behavior:
Not only did a neuron path activate in mice when they were exploring a new object, but a correlation was found between activated neurons, a little-understood part of the brain called the Zona Incerta, and the intensity of curious behavior.
When specific cell neurons were activated the mice were more inclined to spend more time exploring a new object. The research called this “deep investigation” and was measured by the amount of time spent approaching the object, touching the object, or engaging with it.
Conversely when the same neurons were suppressed, the mice showed a lot less interest in the new object. It was found that the activated neuron path led to deeper curious interaction, and less neuron activation correlated to “shallow” investigation or no investigation.
This neuron circuit seems to be responsible for one more component. It this process converts curiosity into action. While curiosity is one of the most cerebral desires in animals and humans, it is a desire that compels actions. The study with mice expanded on findings of another study with chimpanzee’s that showed curiosity was largely visually driven. In this study mice wore little cameras on their heads so scientists can see their attention to a visual trigger activated neuron cells and led to touching the object.
Separating Curious vs Hunt vs Eat:
This conversion from visual trigger to action has previously been difficult to study because such a similar process may tell a cat to pounce. The difference is being able to see action taken purely to discover more information, without survival needs like hunting or eating.
This new study is a breakthrough in what has been a challenge to study curiosity behavior. The study recently published in the journal Science separated curiosity from hunting and eating motivations.
The results showed mice who were not hungry that chose to investigate a “new object” over eating or hunting. Mice were presented with a new object, a live cricket as prey, and a dead cricket that they could eat. However, when the mice had fasted and were hungry, that behavior changed to satiating hunger (the crickets) over curiosity.
In the perceived triad of Hunt, Eat, Investigate – curiosity and exploration stand as an exception to the rule as curiosity drive isn’t as survival based as it’s cousins. What the study with mice indicates for human behavior is that curiosity is a driver that wants to be satiated on its own. Curiosity can be a stand-alone need like hunger that wants to be satiated. For the mice, acquiring new information had it’s own merit and was chosen over a food or hunting instinct. Mice will seek non-essential information just for curiosity’s sake.