“[Attention] is the taking possession of the mind, in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thoughts. … It implies withdrawal from some things in order to deal effectively with others. “ —William James, Principles of Psychology.

In this blog we will explore the process of selective attention, a function of memory. In this article we will discuss selective attention. 

It is not quite easy to describe cognitive functions such as perception, attention, memory or analytical reasoning.

Attention is the means of processing the limited amount of information from the large amount of information available through perception, memory or cognitive resources.

It can be both conscious and unconscious. It is easier to study conscious process than unconscious process simply because process is conscious.

A person tends to have a lot of information but they do not process all the information at a given time as it can become highly overwhelming.

For example, a person knows where they slept at the age of 12 or where they ate their breakfast at the age of 12.

A person also has abundant information from their sensory organs which they do not simply attend to.

All this is conscious information which they do not attend to at a given time but a person knows a little about what information they process when they are asleep which can be understood as an unconscious process. 

By attending to certain stimuli from a large amount of information helps in many cognitive functioning.

Dimming the light on certain stimuli and highlighting others makes us better able to attend to the stimuli of our interest.

By attending better we can respond better and effectively to those stimuli. Attention also helps in the memory process.

Stimuli which are processed better are better consolidated in memory. 

Attention can be both overt and covert.

Overt attention is attending to few of extensive outside stimuli while covert attention is the process of attending to the few of so many memories and thought processes. 

Selective attention:

Selective attention is the ability to consciously attend to a range of characteristics based factors and characteristics of stimuli.

This process occurs simultaneously with filtering out stimuli not of interest to the individual.

This phenomenon lets us select the stimuli that we want to pay attention to. 

Imagine yourself at a party, where you are engaged in a conversation with a person who sells electronics and he engages you with the excruciating details of which brand is better for which electronic.

At the same time your attention diverts to the attention of two other diners who are in a conversation about one of your acquaintances which you find interesting.

In this situation, a person tends to keep up with the boring conversation, mentally filtering it out while attending to the interesting conversation.

This phenomenon is known as the Cocktail Party effect. 

Cocktail party effect is a phenomenon based on selective attention. It is a phenomenon in which an individual tracks a conversation in face of another conversation.

He observed this phenomenon in cocktail parties mostly.

He did not let observation stay in parties but studied it more methodically through an experiment called shadowing. 

In an experiment of shadowing, Colin Cherry asked his participants to listen to two different messages at the same time.

This kind of presentation is known as dichotic presentation. Participants were required to repeat one of the messages and shadow the other one.

Participants of study were pretty successful in shadowing the other message and repeat the one shortly after it was presented.

He also observed that participants noted the changes in physical aspects of other messages but they were not able to decipher the semantics related to other messages.

They observed the change in tone and pitch of the message but couldn’t understand the shift from English to German language.

He also pointed out that when participant’s name was mentioned in shadowed messages participants shifted their attention.

According to Colin cherry, this shift in attention showed little capacity for working memory. 

According to Brungard & Simpson (2007) three aspects are important in selectively attending to the target speaker.

These three aspects are as follow:

• Pitch of the sound
• Loudness of sound 
• Location of sound 

Theories of selective attention:

Since the observation of phenomenon, many theorists have attempted to theorize about the phenomenon of selective attention.

These theories about selective attention belong to two major groups of theories which are as follow:

1. Filter theories: Theories belonging to this paradigm assume that some filters blocks the incoming information thus individual ultimately attend to only specific information 
2. Bottleneck theories: Theories belonging to this paradigm assume that incoming information is slowed down while passing through different stages thus making individuals attend to only certain information. 

Following are theories of selective attention:

Broadbent’s Model of selective attention:

According to Broadbent, information is filtered out at sensory level. Information from the senses reaches to attention filters through multiple channels.

These channels can be distinguished on the basis of physical aspects of stimuli such as pitch, loudness and accent.

At this stage of attention filter, information from only one channel is transferred further to be processed.

According to Broadbent, through the attention filter we assign meaning to sensory information.

Information which is not transferred for perceptual processing is blocked out at the level of sensory filter and may never go through the perceptual process. 

Broadbent’s model of selective attention is supported by Colin Cherry’s experiment of shadowing.

As a person may notice change in the pitch and loudness of voice but this message is not processed further to have semantic understanding of the message.

Thus information which requires higher perceptual processing is not noticed if it is not attended. 

Selective filter model of Selective Attention:

Not long after Broadbent’s model of selective attention, it began to be criticized.

Moray observed that for a higher level of processing, information is needed to be attended.

But they noticed that participants were able to process their names in an unattended message.

From this observation Moray concluded that processed information was important for the person so it broke the filters of attention.

Moray revised Broadbent’s Model of selective attention hypothesizing that information is blocked out at sensory level but some information important for participants is powerful enough to break through the filters of attention and that information is processed other than  information being processed through selective attention.

Attenuation Model of Selective Attention:

To explore the discrepancy in Broadbent’s model of selective attention, Anne Treisman conducted a series of experiment and found following results:

• If a message from the attended ear was transferred to the unattended ear, participants were able to process a few words of unattended ear.
• If message in attended and unattended ear, participants were able to notice it
• If message in unattended ear was translation of message in attended ear, bilingual participants were able to recognize it
• Participants also noticed if the message in unattended and attended ear were slightly out of temporal synchronization

Treimann found that Broadbent’s model of selective attention and Moray modification in the model were not sufficient to explain the results of her experiments.

She came up with another model of selective attention.

According to this model of selective attention, incoming information is not blocked out at attention filters but merely weakens it other than target stimuli.

Thus when the stimuli reaches us we process it at a lower level because of weakened signals.

Stimuli from both the ears reaches the attention filter, if the stimuli has similar properties as those of target stimuli, it will be passed on and analyzed but if it does not have similar properties only weakened signals would be passed on.

Later the information is analyzed and given meaning t.

Thus even the information from an unattended ear can come to consciousness and can have impacts on further analysis. 

Late-Filter Model of Selective Attention:

Deutsch and Deutsch (1963) gave the late filter model of selective attention, in which the filter where the information is filtered is further later in the process of selective attention.

According to them, a message is filtered out only after it has been analyzed for its physical properties and its meaning. 

This late filter allows individuals to process the information in the unattended ear and transfer their attention if they hear their name or if the message in the unattended ear is the mere translation of information in the attended ear.

Both late and early filtering models propose that there is a bottleneck through which information can pass on which is attended to.

These two models only differ in the position of bottleneck.

Neuroscience and Selective attention:

In the 1970s, a groundbreaking discovery was made when researchers used event-related potentials in the study of attention.

This study was conducted by Hillyard and colleagues in 1973. They exposed their participants to two different streams of tones.

Each tone was stimuli of each ear and these streams differed in their pitch.  These stimuli were presented in each ear occasionally.

When the target occurred in the attended ear, the first negative component of event related potential was much larger than when it appeared in the unattended ear.

Negative component can be understood as a wave that appears 90 milliseconds after the first appearance of target stimuli.

According to researchers, a negative wave is a mere increase in target stimuli. Simultaneously, when there was an increase in target stimuli, other stimuli was suppressed.

The researchers hypothesized that the N1 wave was a result of the enhancement of the target stimulus. These results were consistent with filter theories.

Later studies by Woldorff and Hillyard (1991) found earlier reactions to target stimuli just mere after 20-50 milliseconds after the onset of target.

These waves originated in Heschl’s gyri, A part of the brain located in the auditory cortex. 

These methods are still employed by researchers to explore diverse phenomena such as how a child’s selective attention is influenced by the socio-economic status of mother.

The result of study found a strong relationship between a mother’s socio-economic status and child’s selective attention.

Lower socio-economic status of mothers resulted in reduced neural processing for selective attention. 

Conclusion:

Selective attention is a phenomenon in which individuals selectively attend to certain stimuli while filtering or blocking out other stimuli.

This phenomenon was built on the observation of Colin Cherry Cocktail Party effect. Since then many researchers have tried to explore the phenomenon of selective attention and support it through experimental evidence.

Two major groups of theories include filtering on unattended information and blocking of unattended information.

FAQs about Selective Attention

References:

https://www.brainlatam.com/blog/what-is-selective-attention-473

Sternberg, R. J., & Sternberg, K. (2016). Cognitive psychology. Nelson Education.