Broadbent’s rigid filter model

This model proposed by Donlad Broadbent attempts to explain the functioning of attention.

How do we process information, on what does it depend that we select one stimulus and not others, and how can we attend to only one stimulus among many?

Since basic psychology, many authors have focused on the processes of attention, proposing theoretical models of it. Today we are going to know one of them, Broadbent's rigid filter model..

To do so, let's start by seeing what the filter models of attention are, to which this one by Donlad Broadbent belongs.

Attention filter models

Attention filter models focus on the concept of filtering. This consists of choosing a fragment of the sensory stream and giving it access to the central channel of processing.while the rest is lost (selective attention).

There are two types of filter models, which are as follows.

Precategorical filter models

Broadbent's rigid filter model belongs to this type. In these models the selection of information is early, i.e., the attentional mechanism operates in the initial phases of processing..

The process consists of sensory registration (which is performed in parallel, and where the physical characteristics of the stimulus are analyzed), the appearance of the filter (which selects the information it attends to) and finally the appearance of a single central channel where the stimulus comes to be processed semantically (serially).

In these models only properly attended information is processed at the semantic level.

Postcategorical filter models

Here the selection of information is delayed, i.e, the attentional mechanism operates later than in the previous model..

In these models, there is a sensory store that includes an analyzer system (processing of physical and semantic features in parallel and in an automatic/passive way). Then comes the filter, which collects all the signals and selects them.

The next element is short-term memory or central attention mechanism, which actively and consciously analyzes the message (it is a controlled process, which consumes attentional resources).

In these models, unlike the previous ones, all information is processed at a physical and semantic level.

Broadbent's rigid filter model.

This is a pre-categorical filter model, where the filtering goes before the semantic analysis. That is, the stimuli appear first, which will be stored in the sensory store. Then the filter would act, which would select the information.

This would be stored in the short-term memory (a channel of limited capacity), and finally certain information would pass to the long-term memory (between these two elements, the subject's responses to the stimulation would appear).

Here something similar to the "all or nothing law" would apply, i.e., information either passes or it does not (one message is processed at a time).

Characteristics of Broadbent's rigid model

Processing would take place in parallel at the peripheral level.

Sensory memory transiently retains the information.. The filter it proposes is rigid and selective, since it chooses a fragment of the sensory flow and gives it access to the central channel, while the rest of the non-relevant information is lost (this occurs to avoid the overload of the central channel caused by multiple sensory channels).

At the central level, a categorical or semantic analysis of the information is performed, i.e., there is sequential processing and the channel has limited capacity, sequential processing takes place and the channel has a limited capacity..

Characteristics of the Broadbent filter

It is a rigid filter, an "all or nothing" device. The selection of information is made on the basis of the physical characteristics of the stimuli without taking of the stimuli without taking into account the meaning of the messages. Semantic processing will be done later.

On the other hand, the probability that a message will or will not be selected will depend on the properties of the stimuli (spatial location, intensity, speed of presentation, sensory modality...) and the state of the organism.

The filter can only focus on one channel or message at a time, and its transition time is two seconds.and its transition is two seconds.

Deutsch and Deutsch's early selection model

It is important to distinguish between Broadbent's rigid filter model and Deutsch and Deutsch's early selection model. The latter, unlike Broadbent's rigid (pre-categorical) model, is a post-categorical filter model.

In this case, we ask ourselves the following question: how is it possible to select one input among several without analyzing all of them? In order to decide which of the stimuli is relevant, a certain degree of analysis is required. a certain degree of analysis is necessary..

Moreover, in this case there is semantic analysis data prior to selection, which is taken care of by the parser.

Once the stimuli have been received, they are stored in the sensory store, they are stored in the sensory store. Subsequently, an analyzer acts prior to the filter, and the latter will transfer the information to the short-term memory (STM).

Finally, from the MCP it is transferred to the long-term memory (and, as in Broadbent's model, the responses will appear between these two memories, in the transfer from one to the other).

That is, the most important difference from Broadbent's rigid filter model is that in Deutsch's and Deutsche's there is a parser acting prior to the filter.

Bibliographical references:

• García, J. (1997) Psychology of attention. Síntesis. Madrid.
• Munar, E., Rosselló, J. and Sánchez-Cabaco, A. (1999). Attention and perception. Alianza. Madrid.