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Touch, pressure, pain, temperature, proprioception, vision, hearing, smell, and taste are distinct sensory modalities. Receptors are specialized for different stimuli: for example, mechanoreceptors respond to touch and pressure, while photoreceptors respond to light. The law of specific nerve energies and labeled line theory help explain why the pathway activated influences the perception. Receptors may adapt rapidly, emphasizing changes, or slowly, continuing to monitor sustained stimuli. Special-sense pathways illustrate how sensory signals are processed: visual information travels from the retina toward the visual cortex, while hearing signals pass from cochlear hair cells through the auditory nerve pathway. Smell initially reaches the olfactory cortex without passing through the thalamus, and taste signals travel through cranial nerves to the gustatory cortex.