Similarities between the irrelevant sound effect and the suffix effect.

Area of Science:

• Cognitive Psychology
• Auditory Memory
• Speech Perception

Background:

• Articulatory suppression typically eliminates the irrelevant sound effect (ISE) on visual sequence recall.
• However, the ISE persists for auditory list items even with articulatory suppression.

Purpose of the Study:

• To investigate if the ISE on auditory lists under articulatory suppression mimics the suffix effect.
• To determine the characteristics of irrelevant sound that affect auditory memory retention when articulation is suppressed.

Main Methods:

• Two experiments were conducted using articulatory suppression.
• Experiment 1: Compared recall with instrumental music vs. silence.
• Experiment 2: Compared recall with irrelevant speech from the same vs. different voice as list items.

Main Results:

• Instrumental music did not produce an ISE under articulatory suppression, but speech-based irrelevant sound did.
• The ISE was stronger when the irrelevant speech matched the voice presenting the list items.
• These findings align with known characteristics of the suffix effect.

Conclusions:

• When articulation is suppressed, irrelevant sound disrupts auditory memory by interfering with acoustic-perceptual encoding.
• The irrelevant sound must contain speech, and vocal matching enhances the effect.
• The findings do not support interference within a postcategorical phonological store.