Skip past navigation to main part of page
 
Faculties : A-Z Directory : Library
Skip past navigation to main part of page
---

Change Deafness Demonstration


The demonstrations contained on this site accompany the following manuscript:

Eramudugolla, R., Irvine, D.R.F., McAnally, K.I., Martin, R.L. & Mattingley, J.B. (in press). Directed attention eliminates 'change deafness' in complex auditory scenes. Current Biology.

Back to Cognitive Neuroscience Laboratory

Background

When listening to complex auditory scenes consisting of multiple concurrent, naturalistic sound sources (or 'objects'), normal listeners can readily distinguish and recognize the individual objects that comprise the acoustic input. However, this does not guarantee that listeners will simultaneously be aware of all the objects in the scene. The 'change deafness' phenomenon reveals a striking limitation in normal listeners' ability to detect salient changes in complex auditory scenes consisting of as few as six objects.

Instructions

The change-deafness demonstration contained on this site consists of auditory stimuli in .wav file format. You will need headphones to listen to the stimuli as they have been recorded in virtual auditory space' (VAS). VAS stimuli simulate the natural experience of listening, in which sounds are heard at locations external to the head.


Task 1

Object Library

 

This section contains eleven separate recordings of the different sound 'objects' that will comprise the auditory scenes. Listen first to each of these brief sound files to familiarize yourself with the auditory objects. (Note that the sounds for this part of the demonstration are not presented in VAS.)
 

beat (430kb)
hens (430kb)
siren (430kb)

birds (430kb)
man (430kb)
trumpet (430kb)

 cello (430kb)
piano (430kb)
woman (430kb)		 chant (430kb)
ring (430kb)

The 'non-directed attention condition' and 'directed attention condition' sections contain samples of the auditory change-detection trials. Each file comprises a five second presentation of an auditory scene, followed by a 500 ms noise burst, and then a second version of the auditory scene in which one of the auditory objects will have disappeared. There are three examples of change-detection trials in each section, representing scene sizes of four, six and eight objects.

Task 2

Directed Attention Condition
 

The following filenames indicate the name of the sound object that will disappear from the scene in each trial. Listen to the object identified in the filename (e.g., hens in the file: '6 objects hens disappear.wav') and determine whether that object disappears from the scene (following the noise burst).

4 objects: birds disappear (1.76mb)
6 objects: hens disappear (1.76mb)
8 objects: cello disappears (1.76mb)

Task 3

Non-Directed Attention Condition
 

The following filenames indicate the number of objects in the scene, but not which object will disappear. Listen to all the objects and detect whether any object disappears from the second version of the scene (following the noise burst).

4 objects (1.76mb)
6 objects (1.76mb)
8 objects (1.76mb)

You should find that it becomes more difficult to detect a change in the non-directed attention condition as the size of the scene increases. In contrast, you should have little or no difficulty detecting a change when you direct attention to the object that might change, regardless of the scene size. Note that in the studies described in the manuscript 75% of trials contained a change and 25% contained no change, and these trial types were randomly intermingled.


 

 

 --- Schematic of a virtual auditory space scene containing 6 auditory objects. The icons around the listener's head represent the auditory objects and the azimuthal locations at which they were generated. (A) In the non-directed condition, attention was not cued to any object in the scene. Participants indicated whether any object (the cello in this example) had disappeared from the scene. (B) In the directed condition, attention was cued to one object (indicated by the box) and participants determined whether that object disappeared. From: Eramudugolla et al.

Schematic of a virtual auditory space scene containing 6 auditory objects. The icons around the listener's head represent the auditory objects and the azimuthal locations at which they were generated. (A) In the non-directed condition, attention was not cued to any object in the scene. Participants indicated whether any object (the cello in this example) had disappeared from the scene. (B) In the directed condition, attention was cued to one object (indicated by the box) and participants determined whether that object disappeared. From: Eramudugolla et al. (in press). Current Biology.

top of pagetop of page

Contact us

Contact the University : Disclaimer & Copyright : Privacy : Accessibility