Simple reaction-times to speech and non-speech stimuli

Area of Science:

• Cognitive Psychology
• Psycholinguistics
• Human-Computer Interaction

Background:

• Reaction time (RT) is a fundamental measure in cognitive psychology, assessing the speed of cognitive processing.
• Understanding the differences in RT between speech and non-speech stimuli is crucial for designing effective communication systems.

Purpose of the Study:

• To measure and compare simple reaction-times to speech versus non-speech stimuli.
• To investigate the influence of stimulus-response compatibility in speech-based tasks.
• To determine the processing time associated with speech reception and motor speech production.

Main Methods:

• Two experiments were conducted measuring reaction times.
• Experiment 1: Subjects responded with speech (vowel [a:]) to speech ([a:]) and non-speech stimuli (tone, bell, click).
• Experiment 2: A 2x2 design examined speech ([a:]) vs. non-speech (bell) stimuli with speech (vowel [a:]) vs. non-speech (key-press) responses.

Main Results:

• A short-duration click (25 msec) resulted in significantly longer reaction times compared to other stimuli equated for intensity.
• No significant effect of stimulus-response compatibility was found in the first experiment.
• Speech stimuli and responses yielded significantly longer reaction times than non-speech stimuli and responses in the second experiment.

Conclusions:

• The minimum reaction time for speech reception is approximately 180 msec.
• Utilizing the motor speech mechanism adds about 30 msec to overall reaction time.
• The lack of stimulus-response interaction in these simple tasks suggests the tasks were not complex enough to reveal such effects.