What Part Of The Brain Sets Humans Apart From Animals

SA Mind

What Are the Structural Differences in the Brain between Animals That Are Self-Aware (Humans, Apes) and Other Vertebrates?

Robert O. Duncan, a behavioral scientist at York College, the City University of New York, responds

What are the structural differences in the brain betwixt animals that are cocky-aware (humans, apes) and other vertebrates?
— Emma Schachner, Common salt Lake Metropolis

Robert O. Duncan, a behavioral scientist at York Higher, the City University of New York, responds:

Cocky-awareness distinguishes humans from most other species. In psychology, self-sensation is defined as metacognition, sensation of 1'due south own ability to remember. In humans, metacognition and other advanced cognitive skills, such as social intelligence, planning and reasoning, are all thought to depend on a region of the brain chosen the prefrontal cortex.

If we assume that the prefrontal cortex permits metacognition, then the answer is uncomplicated: species that fail to demonstrate metacognition tend to lack brain areas that resemble the prefrontal cortex. Only considering this expanse serves many cognitive functions and is well connected to the rest of the brain, the region is probably not the sole locus of metacognition. In other words, the prefrontal cortex may be necessary but not sufficient for self-awareness. Some psychologists speculate that self-awareness may ascend in animals with greater overall cognitive ability, larger encephalon size or a higher degree of connectivity among brain areas.

Identifying the precise structural differences that make some creatures self-aware and others not is quite challenging. Near important, it is difficult to pinpoint and compare subtle structural differences across species in the face of more dramatic differences in brain morphology. For instance, dolphins and chimpanzees both demonstrate metacognition, but their brains wait completely different.

Additionally, simply identifying which species showroom self-aware behavior has proved tricky because no reliable behavioral tests for the trait exist. In 1970 Gordon 1000. Gallup, Jr., of the University at Albany, Due south.U.N.Y., developed the "mirror test" to appraise metacognition in chimpanzees. A chimp passes the test if it uses the mirror to inspect a marker that has been painted on its face up. Although the majority of chimps pass, some do neglect, causing certain scientists to consider the examination unreliable.

The difficulties nosotros have assessing self-awareness demonstrate that it is a circuitous trait and support the idea that no single brain area is dedicated to information technology. Overall, the prefrontal cortex may be critical for metacognition, but self-awareness most probable emerges when this region is highly interconnected with the rest of the brain.

This article was originally published with the title "Ask the Brains" in SA Mind 23, one, 70 (March 2012)

doi:x.1038/scientificamericanmind0312-70