Definition

1. Noun:
   • A psychophysical principle: The Weber-Fechner law is a concept in psychophysics stating that the perceived magnitude of a subjective sensation increases in proportion to the logarithm of the physical intensity of the stimulus. It synthesizes early foundational work by Ernst Heinrich Weber and Gustav Theodor Fechner.

Usage Examples

• Noun:
  • The Weber-Fechner law describes the logarithmic relationship between stimulus intensity and perceived sensation.
  • According to the Weber-Fechner law, doubling the physical intensity of a sound does not double its perceived loudness.

Advanced Usage

• "to obey the Weber-Fechner law": to follow the logarithmic principle of perception.
  • The perception of brightness in many visual contexts appears to obey the Weber-Fechner law.

Variants and Related Words

• Fechner's law (n): A synonymous term for the Weber-Fechner law, emphasizing Gustav Fechner's formulation.
  • Fechner's law is a cornerstone of classical psychophysics.
• Weber's law (n): A related, foundational principle stating that the just-noticeable difference between two stimuli is proportional to the magnitude of the original stimulus. This is a key component integrated into the Weber-Fechner law.
  • Weber's law concerning weight discrimination was a precursor to the broader Weber-Fechner law.

Synonyms

• Psychophysical law: A general term for a mathematical relationship between physical stimulus and psychological experience.
• Logarithmic law of sensation: A descriptive synonym highlighting the mathematical form of the relationship.

Related Phrases

• Stimulus intensity: The physical magnitude or strength of a stimulus (e.g., brightness, weight, sound pressure).
• Subjective sensation: The internal, psychological experience resulting from a stimulus (e.g., brightness, heaviness, loudness).

Noun

1. (psychophysics) the concept that the magnitude of a subjective sensation increases proportional to the logarithm of the stimulus intensity; based on early work by E. H. Weber