Monday, 6 February 2017
UNI ESSAYS How do psychologists explain the fact that we are able to ignore much of the auditory information that bombards us?
Dichotic listening is a task used in cognitive psychology to investigate selective attention in the auditory system. During a dichotic listening task, the participant will be presented with two different auditory stimuli, one in each ear, and asked to distinguish one or both of the stimuli.
In 1953, E Colin Cherry first identified the 'cocktail party phenomenon' which references the ability to listen selectively to one conversation during a party whilst ignoring other background noise. Cherry used the dichotic listening task to investigate this. In his experiment, Cherry played a separate message to each ear of the participant who is then asked to shadow once message. This is to ensure that the participant is attending to the shadowed message. From this experiment, Cherry found that participants were only able to report the physical characteristics presented in the unattended message such as whether the message was being relayed by a male or female voice. The participant was not able to to distinguish what language the message was being relayed in.
In 1958, Broadbent proposed a filter model to explain Cherry's findings. His model explained that, in order to prevent us becoming overwhelmed by sensory input, there is an 'attentional filter' that blanks out all but the desired information from being processed. Broadbent's filter model showed that information is filtered very soon after entering the perceptual system. Only one input is allowed through the system. All other inputs are caught in an attentional 'bottleneck'. However in 1959, Moray found that people could recognise their own names in an unattended eat thus proving Broadbent's theory wrong. In 1964, Treisman proposed a theory of selective attention. Her theory argued that all messages were being processed beyond the sensory stage but unattended messages were subject to attenuation. Treisman's attenuator model shows that the input is attenuated to very soon after entering the perceptual system. The attenuated inputs are caught in a similar 'bottleneck'. The central problem with this model is the lack of clarity to the meaning of attenuation. A similar theory was proposed by Deutsch & Deutsch in 1963. Similarly to Treisman's theory, Deutsch & Deutsch's theory proposed that all incoming information is fully processed. There is no 'bottleneck' in their model and once input is given precedence nearer the time when a response has to be made.
Each of these theories make valid contributions to the idea of selective attention. However, neither of these theories highlight how demanding a task shadowing actually is. It is possible that the unattended message is being fully processed but is not stored in the short term memory long enough for a response to be made. Von Wright, Anderson & Stenman (1975) presented target words that had previously been associated with electric shocks. They detected a physiological reaction to inputs in both ears which shows that the unattended inputs were fully processed.
Resource allocation theories propose that people can multi-task, carrying out more than one attention demanding task at a time.In 1973, Kahneman proposed a model that shows that some activities are more demanding and therefore require more mental effort than others and that the total available processing capacity may be increased or decreased by factors such as arousal. Navon & Gopher (1979) proposed a slightly more complex model that allows two separate modalities of attentional resources. Yantis (1994) criticised these theories for being too broad and too vague whereas Stenberg (2003) proposed that these theories complemented the filter theories.
Broadbent, D .,(1958) Perception and Communication, Oxford: Pergamon Press
Cherry, C. E., (1953) Some experiments on the recognition of speech, with one and two ears, Journal of the Acoustical Society of America, 22, 975-979
Deutsch, J. A., & Deutsch, D., (1963), A study of normative and informational social influences upon individual judgements, Journal of Abnormal and Social Psychology, 51, 629-636
Moray, N., (1959) Attention in dichotic listening: affective cues and the influence of instructions The Quarterly Journal of Experimental Social Psychology, 11 56-60
Treisman, A. M., (1964) Verbal cues, language and meaning in selective attention, American Journal of Psychology 77(2) 206-219
Von Wright, J. M., Anderson, K., & Stenman, U. (1975). Generalisation of conditioned GSRs in dichotic