502. Angry and Red: Color as Emotion | Mark Changizi

Emerging theories suggest that human color vision evolved as a mechanism to better interpret social and health-related cues from others, not solely for environmental tasks such as identifying ripe fruit.

Theories propose that human color vision evolved to enhance the detection of emotional and health cues in others, rather than just for identifying ripe fruit.

Mark Changizi and Jordan Peterson explore the evolution of color vision, suggesting it serves a broader purpose in social interaction than previously thought. They delve into the intricate relationship between color perception and our ability to discern emotional states and physical well-being.

The unusual, close-together placement of the middle and long wavelength color receptors in the human eye is optimized for detecting variations in skin tone and blood oxygenation, which are important signals of an individual's emotional state and physical health.

Changizi proposes that the traditional hypothesis, which links primate color vision to fruit detection, lacks strong evidence. Noting the similarity in color vision across varied primate diets, he points to the unique arrangement of the middle and long-wavelength color receptors in the eye. Instead of being spread across the visual spectrum like an RGB camera, these receptors are situated closely together in terms of wavelength sensitivity—an arrangement that seems to be fine-tuned for detecting subtle changes in skin tone rather than fruit.

These receptivity patterns align with the spectrum of hemoglobin changes between its oxygenated and deoxygenated states. Changizi elaborates that our color vision's fine sensitivity to these changes is due to the specific placement of the relevant cones in our eyes. This sensitivity allows us to detect signals produced by blood circulation under the skin, which convey a person's emotional state and health.

Changizi also notes that certain emotions can cause different color gradients on the face. Moreover, the entire body can exhibit color variations connected to emotional and health statuses. This capability is particularly evident in primates with color vision, wh ...

In a conversation between Changizi and Peterson, the importance of emotional expression and reputation is put forth as a central factor in human social interaction and communication.

Emotional expressions and the staking or ceding of social capital serve as a decentralized currency that enables cooperative and competitive negotiations between individuals.

Emotional displays that are outside voluntary control, like blushing or genuine laughter, function as honest signals of an individual's internal state and intent, facilitating social cooperation and trust.

Changizi and Peterson discuss the role of blushing as an honest signal. This involuntary response can indicate self-conscious shame and the inability to get away with violating social norms, thus facilitating social trust. Our faces and skin, especially our faces, function as mechanisms to display emotion, allowing others to read our intentions and desires. Honest signals, such as genuine laughter and spontaneous smiles, are clear, outward signs that make it easier for others to trust and engage in cooperative interactions because they suggest that a person is showing their true emotions and intentions.

The maintenance of reputation through reciprocal interactions and the management of social capital is critical for regulating both cooperative and competitive social dynamics.

Changizi suggests that before social signaling evolved, animals like sharks felt emotions but did not need to communicate them. In contrast, social animals require an optimal signaling system to negotiate and compromise without spoken language. Emotional expressions function as non-verbal negotiation tools, similar to staking chips in poker.

Peterson brings up the concept of reciprocal play among animals like juvenile rats, which establishes social order. Successful hunters in hunter-gatherer societies should manage their reputation and not hoard physical rewards to ensure cooperation and minimize jealousy within the group.

Changizi ties emotional expressions directly to color modulations that may be visible through our color vision, suggesting that our sense may have evolved to detect honest emotional signals such as blushing.

Moreover, reputation, bolstered by past generous actions, increases the likelihood of receiving future help if faced with difficulties. Changizi and Peterson discuss that ensuring a good reputation through actions is key to thriving within a social group.

Changizi compares social narratives to blockchain, a system that preserves reputation over time. These narratives, while crucial for maintaining social order, can perpetuate historical falsehoods or stereotypes.

On the internet, anonymity can lead to misbehavior due to the lack of reputational consequences. However, daily encounters with strangers ...

The origins and evolution of human language, writing, and music have been a significant focus of scientific inquiry. These cultural and cognitive adaptations appear to have evolved to align with our sensory and perceptual capabilities, enabling the development of sophisticated communication forms.

Written language and orthographies have evolved to match the visual patterns and features that the human visual system is optimized to process, enabling the development of reading as a near-universal human skill.

Mark Changizi outlines the evolutionary process that has shaped written language to resemble natural visual scenes that the human visual system is adept at processing. Changizi states that writing has culturally evolved to look like natural objects, which allows people to read with apparent ease, often at a very young age with minimal practice. This suggests that reading operates similarly to an instinct, given there are areas in the brain associated specifically with visual word recognition. Cultural evolution has shaped the appearance of written language to employ patterns and features such as L and T junctions, emulating the intersections and overlaps that occur when objects in our environment interface with each other. He explains that there are 32 topologically distinct junctions involving three contours that occur in natural scenes, and these types of junctions appear in human writing systems proportional to their occurrences in nature.

The regular structural elements of spoken language, such as the distinction between consonants and vowels, mirror the acoustic patterns generated by the physical interactions of objects in the natural world, providing a foundation for the human capacity for speech and language.

Changizi further suggests that spoken language has evolved to sound like solid object physical events. For example, plosives such as "puh," "duh," and "kuh" mimic collisions, while fricatives and sonorants imitate sliding sounds and vibrations, or ringing, respectively. The concept of a syllable, described as a "hit and a ring," reflects the natural sound of a collision followed by a subsequent resonance. Mathematical regularities in the physical events of solid objects interacting are mirrored as universals in human language across different cultures.

Music has evolved to mimic the sounds and rhythms of human movement and physical interactions, engaging the perceptual systems that evolved to process and understand the kinematics of the body in motion, which enables the strong emotional and social effects of music.

Music is intrinsically different from speech but evokes a sense of the sounds of human movement. Elements such as the rhythm of footsteps (gait) are mirrored in music through beats and loudness modulations that create a narrative of human k ...