Web-based auditory experiment

This is an experiment on auditory awareness. In order to participate in this experiment you need to listen to an audio file (step #1). After that, you have to answer two questions about what you heard (step #2). You will then be given further information about the purpose of the experiment (debrief/step #3). It is important that you follow the experimental sequence below in order.

Step #1. Start the auditory experiment
Please listen to the following binaural recording (it is important that you use headphones). Afterwards you will be asked several questions about what you heard – so listen carefully…
Put on your headphones and click the play button below when you are ready to start the listening task.

After listening you can continue with step #2 below.

Step #2. Your responses

(1) Did you hear anything unusual that didn’t fit in with the scene?

(2) Did you hear anyone other than the four people preparing for the party?

Please prove you are human by selecting the Car.

Step #3. Debrief

Emprical results show that on average 50% of participants completely miss the “auditory gorilla”. Did you hear it? If not, listen again and you will be surprised how you could miss it in the first trial. This experiment tells us a lot about the inherent limits and the task-specificity of attentional resources. The phenomenon is called “inattentional blindness”. Our attention has been metaphorically compared to a spotlight which only illuminates a small proportion of the vastness of reality.

Inattentional blindness or perceptual blindness (rarely called inattentive blindness) occurs when an individual fails to perceive an unexpected stimulus in plain sight, purely as a result of a lack of attention rather than any vision defects or deficits.
The term was chosen by Arien Mack and Irvin Rock in 1992 and was used as the title of their book of the same name, published by MIT Press in 1998, in which they describe the discovery of the phenomenon and include a collection of procedures used in describing it.

The original article associated with the experiment at hand was published by Dalto & Fraenkel (2012) in the journal ‘Cognition’.

Dalton, P., & Fraenkel, N.. (2012). Gorillas we have missed: Sustained inattentional deafness for dynamic events. Cognition, 124(3), 367–372.

Plain numerical DOI: 10.1016/j.cognition.2012.05.012
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A famous study that demonstrated inattentional blindness asked participants whether or not they noticed a person in a gorilla costume walking through the scene of a visual task they had been given. Research on inattentional blindness suggests that the phenomenon can occur in any individual, independent of cognitive deficits. However, recent evidence shows that patients with ADHD (Attention deficit hyperactivity disorder) performed better attentionally when engaging in inattentional blindness tasks than control patients did, suggesting that some mental disorders may decrease the effects of this phenomenon. Recent studies have also looked at age differences and inattentional blindness scores, and results show that the effect increases as humans age.

Simons, D. J., & Chabris, C. F.. (1999). Gorillas in Our Midst: Sustained Inattentional Blindness for Dynamic Events. Perception, 28(9), 1059–1074.

Plain numerical DOI: 10.1068/p281059
directSciHub download

Listen to the associated interview on RadioCognovia