Top-down and bottom-up interaction: manipulating the dichotic listening ear advantage

Brain Res. 2009 Jan 23:1250:183-9. doi: 10.1016/j.brainres.2008.10.070. Epub 2008 Nov 11.

Abstract

The aim of the study was to investigate interactions between top-down and bottom-up information processing in the auditory domain. For this purpose, thirty-five right-handed participants with normal hearing acuity were tested with consonant-vowel dichotic stimulus pairs. Bottom-up stimulus characteristics were manipulated by gradually varying interaural intensity difference from -21 dB in favor of the left ear to +21 dB in favor of the right ear (including a no difference baseline condition). Top-down manipulation consisted of three conditions with different attention instructions: one free report condition, and each one condition requiring the participants to focus their attention on the right ear and on the left ear, respectively. The results showed a significant interaction of bottom-up and top-down manipulations with respect to the modulation of the ear advantage. Post-hoc analysis showed that the effect of directing attention was reduced when the intensity difference favored the to-be-attended ear. Thus, bottom-up intensity and top-down attention manipulations should not be regarded as independent but rather interacting factors when it comes to the manipulation of the ear advantage in a dichotic listening situation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Analysis of Variance
  • Attention*
  • Auditory Perception
  • Cognition
  • Dichotic Listening Tests*
  • Female
  • Functional Laterality
  • Humans
  • Male
  • Models, Neurological*
  • Sound
  • Young Adult