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

From basic psychology, many authors have focused on the processes of attention, proposing theoretical models of it. Today we will know one of them, the Broadbent rigid filter model .

To do this, let’s start by looking at what the attention filter models are, to which this one by Donlad Broadbent belongs.

Attention filter models

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

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

Precautionary 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 a sensory recording (which is done 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 becomes semantically processed (in series).

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

Post-categorical filter models

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

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

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

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

Broadbent’s rigid filter model

This is a precategorical filter model, where the filter goes before the semantic analysis . This means that the stimuli are displayed first and 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 go into 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., the information passes or does not pass (one message is processed at a time).

Characteristics of the Broadbent rigid model

Processing would be done in parallel at the peripheral level.

The sensory memory retains information temporarily . The filter it sets up 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 overloading the central channel caused by multiple sensory channels).

At a central level, a categorical or semantic analysis of the information is carried out, i.e. there is sequential processing and the channel is of limited capacity .

Broadbent filter characteristics

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

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

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

The early selection model of Deutsch and Deutsch

It is important to distinguish between the rigid filter model of Broadbent and the early selection model of Deutsch and Deutsch. The latter, in contrast to the rigid Broadbent model (pre-categorical), 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 them all? In order to decide which of the stimuli is relevant a certain degree of analysis is necessary .

In addition, in this case there are data from semantic analysis prior to selection, which are dealt with by the analyser.

Once the stimuli are received, they are stored in the sensory store . Subsequently, an analyzer acts previously to the filter, and this last one will transfer the information to the short term memory (MCP).

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

That is, the most important difference to the Broadbent rigid filter model is that in the Deutsch and Deutsche model there is an analyzer that acts prior to the filter.

Bibliographic references:

  • García, J. (1997) Psicología de la atención. Síntesis. Madrid.
  • Munar, E., Rosselló, J. and Sánchez-Cabaco, A. (1999). Attention and perception. Alliance. Madrid.