Perception is the process of becoming aware of what our senses are detecting in our surroundings. Columbia University neuroscientists have identified brain-cell circuitry in fruit flies that converts raw sensory signals into color perceptions that guide behavior, as reported in the journal Nature Neuroscience. Colors are not inherent outside of our brains but are constructs created by the brain to make sense of different wavelengths of light detected by the eyes. This process of turning sensory signals into perceptions helps organisms survive and thrive by making sense of the environment.
Specific networks of neurons in fruit flies have been discovered by the research team that respond selectively to various hues, such as violet and ultraviolet wavelengths. These hue-selective neurons are located in the optic lobe, which is responsible for vision. Animals have neurons that respond selectively to different colors or hues, but the neural mechanisms behind hue selectivity have not been fully understood until now. The availability of a fly-brain connectome, which maps the connections between neurons and synapses, has helped researchers develop a diagram representing the neuronal circuitry behind hue selectivity.
By using mathematical models based on their observations of brain cells, the researchers were able to simulate and probe the activities and capabilities of the neural circuits. These models help to make sense of the complexity of the brain cells and their interconnections. Recurrence, a type of cell-to-cell interconnectivity where outputs circle back to become inputs, was shown to be crucial for hue selectivity. Disrupting part of this recurrent connectivity in the brains of fruit flies led to the loss of hue-selective activity in neurons, further confirming the role of this brain circuitry in color perception.
The discovery of brain circuitry involved in color perception provides insights into how the brain’s wiring enables the building of a perceptual representation of color. Understanding how the brain produces perceptions, including color, sound, and taste, can help shed light on how brains make sense of the world around them. The neural principles underlying color perception may offer clues on how brains extract important features from the environment that help organisms navigate their daily lives. By unraveling the mechanisms behind color perception, researchers hope to gain a better understanding of how brains process and interpret sensory information.
The ability to perceive and distinguish colors is vital for many organisms to survive and thrive in their environments. The discovery of specific hue-selective neurons in fruit flies sheds light on the neural mechanisms involved in color perception. Mathematical modeling techniques have revealed the complexity of brain circuitry responsible for processing color information, providing a foundation for further research. Disruptions to the recurrent connectivity within these circuits have been shown to affect color perception, highlighting the importance of these neural mechanisms in creating perceptions of the world. These findings contribute to the broader understanding of how brains interpret sensory information and create meaningful perceptions of the world.