What is te difference between labeled line theory and acros fiber pattern theory?

Answer 1

labeled lines theory: Different qualities of a percept such as hot versus cold, sweet versus salty are encoded by separate group of cells. The information within a series of cells transmitting information to the brain remains within separate channels or lines.

Pattern theory.

Differences in the spatio-temporal pattern of electrical activity within a group of cells encode different qualities.

HI!!!...

"Most sensory receptors are maximally sensitive a single stimulus energy, a property sometimes termed receptor specificity. Specificity is a key property of receptors and underlies the most important coding mechanism for stimulus modality, the labeled line code. The axons of receptors function as modality-specific line of communication between the periphery and the central nervous system carrying information about a specific modality. Whether pain or touch is perceived depends on the central connections of the receptors (different types of receptors have different sets of connections in the central nervous system). Thus, excitation of a particular receptor, wether by a natural stimulus or artificially by direct electrical stimulation, always elicits the same sensation.

Not all sensory information is transmitted by labeled line codes. A relatively uncommitted receptor (or neural pathway) can signal different modalities by using different patterns of firing, called a pattern code. Certain types of chemoreceptors lack specificity to a single stimulus. It is thought that different modalities of chemical stimulation (for example, different aspects of taste) are elicited by different discharge patterns of chemoreceptors"

by John H. Martin "Coding and Processing of Sensory Information". Book: Principles of Neural Science.

Answer 2

The labeled line theory suggests that individual sensory receptor cells respond to specific stimuli and transmit this information directly to the brain. In contrast, the across-fiber pattern theory proposes that the brain interprets sensory information based on the pattern of activity across a population of receptors, rather than individual receptors responding to specific stimuli. Essentially, labeled line theory focuses on specificity in sensory coding, while the across-fiber pattern theory emphasizes distributed patterns of activity.