The gustatory system is the sensory system responsible for the perception of taste. It involves specialized receptors on the tongue, known as taste buds, which detect chemical compounds in food and drink, allowing the brain to categorize flavors into basic tastes like sweet, sour, salty, bitter, and umami.

While the source answer identifies 'Only on one's taste buds' as correct, modern sensory psychology emphasizes that flavor is a multisensory experience involving gustation (taste buds), olfaction (smell), and somatosensation (texture and temperature). The provided answer is technically incomplete based on current scientific understanding of flavor perception.

Brightness is a fundamental attribute of visual perception that refers to the perceived intensity of light reflected from or emitted by an object. Unlike auditory qualities such as tone or volume, brightness is exclusively associated with the visual system's processing of light waves and luminance levels.

Sensation is the physiological process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment. When light waves strike the retina, they trigger neural impulses that are sent to the brain. This is distinct from perception, which is the subsequent process of organizing and interpreting those sensory signals to give them meaning. Sensation is the raw input, while perception is the cognitive interpretation of that input.

Psychological research into somatosensation identifies four distinct basic skin senses: pressure, pain, warmth, and cold. All other complex tactile experiences, such as itching or tickling, are believed to be combinations or variations of these four fundamental sensory inputs processed by the nervous system.

Proprioception is the body's ability to sense its own position, orientation, and movement in space. It relies on sensory receptors located in muscles, tendons, and joints, which send continuous feedback to the brain. This system is essential for coordination, balance, and the execution of smooth, purposeful physical actions without needing constant visual monitoring.

Light is electromagnetic radiation that exhibits properties of both waves and particles (photons), and its brightness is measured by intensity. Photoreception, however, is not a characteristic of light itself; rather, it is the biological process by which organisms detect and respond to light through specialized cells in the retina. Therefore, it is a physiological process, not a physical property of light.

In the physics of light, the wavelength of a light wave corresponds to the perceived hue (color), while the amplitude or height of the wave corresponds to the perceived brightness or intensity of the light stimulus.

The iris is the colored, muscular ring of the eye that controls the size of the pupil. By expanding or contracting, the iris regulates the amount of light entering the eye. In bright conditions, the iris constricts the pupil to limit light, while in dim conditions, it dilates the pupil to allow more light to reach the retina.

Sensation refers to the initial detection of physical stimuli, such as individual sound pitches, by sensory receptors. Perception, by contrast, involves the brain's interpretation of these sensations into meaningful experiences, such as recognizing a melody. The question asks for the process corresponding to the initial detection of pitches, which is sensation. This distinction is fundamental to understanding how humans process sensory input from the environment into coherent mental representations.