Auditory cognition occurs when an audio signal changes its mechanical nature, progresses through mechanical and hydrodynamic states, and ends as an electrochemical signal at the auditory cortex. The diaphragms, levers, and sensitivity hairs enable the ear to cope with a frequency range of 20Hz to 16-20Hz (TURNER, John and Pretlove, A.J., 1991). Perception of sound depends on the decoding processes of the brain. To interpret the pitch of a sound instantly, each pitch-selective neuron in the primary auditory cortex directly connected to and dedicated exclusively for a segment of the basilar membrane to interpret the pitch of a sound instantly. This unique perceptual stimulus one-to-one neural mapping has no equivalent in any other sense.

Part of preliminary pitch and speech processing occurs in the brain stem as raw data. Electrochemical signals travel from the cochlea to the primary auditory cortex via the brain stem and the primitive, subcortical brain is triggered immediately with stimulus detection. The cerebellum decodes the rhythm, and the thalamus assesses the signal, ready to trigger a subconscious survival reflex. The thalamus then signals the amygdala to generate an emotional response (BALL, Phillip, 2011). This low-level decoding occurs before any complex cognitive processes as a primary startle response of alertness.

Once the primal evaluation is complete, all high-level processes commence and continuously register neural projections from sensory receptors and low-level processing regions. This process is termed bottom-up processing in which properties of the collected signal are separable and can change independently. Different neural circuits manage the information carried by the stimulus. Through a top-down process, high-level centres update the input data steadily, read only the overall cognitive information, and influence low-level modules. This two-way exchange integrates these signal attributes into a perceptual whole (LEVITIN, Daniel J, 2007).

The prefrontal cortex manages high-level processes such as awareness and expectations, which are the result of associations that the hippocampus creates by correlating the received signal to retained memories. The language centre (Broca) of the prefrontal cortex evaluates syntactic aspects of sound (e.g., speech or music) by transcribing pitch into language. The principal attribute in aural cognition is pitch analysis. Pitch concatenations encode an entire spectrum of sound dimensions, and the brain commissions separate modules to execute each dimension. Pitch dissection leads to melody processing, harmonic structuring, and distinct voice and timber identification. Pitch and rhythm are also the general audible characteristics required to decipher speech and ambient sound. Rhythm and event duration provide clues for pitch qualities and trigger motor responses (BALL, Phillip, 2011). This motor response explains the motivation to dance when listening to intricate rhythmic songs, and the emergent behaviour of falling into step on a crowded street (WITEK, Maria A. G. et al., 2014).