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Effects of expectations on loudness and loudness difference
Scott Parker1, Julianne M Moore, Sara Bahraini
1Department of Psychology, American University, Washington, DC 20016-8062, USA. sparker@american.edu
Attention, Perception & Psychophysics
|June 7, 2012
Summary
Sound perception is influenced by expectations. Expecting loud sounds decreased loudness estimates, while expecting soft sounds increased them, demonstrating top-down control in auditory processing.
Area of Science:
- Auditory perception
- Psychophysics
- Cognitive neuroscience
Background:
- Auditory perception is influenced by various factors, including context and prior expectations.
- Understanding how subjective expectations modulate objective sensory input is crucial for cognitive science.
Purpose of the Study:
- To investigate the impact of auditory expectations on loudness perception and perceived loudness differences.
- To determine if expecting loud or soft sounds alters subjective loudness estimations.
Main Methods:
- Two experiments were conducted involving human subjects.
- Subjects were assigned to conditions expecting loud sounds (L), soft sounds (S), or no specific expectation (control).
- Participants estimated the loudness of tones and the loudness difference between tone pairs.
Main Results:
- In Experiment 1, loudness estimates were highest for soft-sound expecters (S) and lowest for loud-sound expecters (L).
- Control group estimates were intermediate, closer to the soft-sound expectation group.
- In Experiment 2, loudness difference estimates were lowest for loud-sound expecters (L) and highest for control subjects.
Conclusions:
- Auditory perception of loudness and loudness differences is significantly modulated by top-down expectations.
- Results are explained by range-frequency theory and a top-down controlled auditory gain control mechanism.
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