The Construct of Attention in Schizophrenia

doi:10.1016/j.biopsych.2008.02.014

Biological Psychiatry

Volume 64, Issue 1, 1 July 2008, Pages 34-39

https://doi.org/10.1016/j.biopsych.2008.02.014 Get rights and content

Schizophrenia is widely thought to involve deficits of attention. However, the term “attention” can be defined so broadly that impaired performance on virtually any task could be construed as evidence for a deficit in attention, and this has slowed cumulative progress in understanding attention deficits in schizophrenia. To address this problem, we divide the general concept of attention into two distinct constructs: input selection, the selection of task-relevant inputs for further processing; and rule selection, the selective activation of task-appropriate rules. These constructs are closely tied to working memory, because input selection mechanisms are used to control the transfer of information into working memory and because working memory stores the rules used by rule selection mechanisms. These constructs are also closely tied to executive function, because executive systems are used to guide input selection and because rule selection is itself a key aspect of executive function. Within the domain of input selection, it is important to distinguish between the control of selection—the processes that guide attention to task-relevant inputs—and the implementation of selection—the processes that enhance the processing of the relevant inputs and suppress the irrelevant inputs. Current evidence suggests that schizophrenia involves a significant impairment in the control of selection but little or no impairment in the implementation of selection. Consequently, the CNTRICS (Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia) participants agreed by consensus that attentional control should be a priority target for measurement and treatment research in schizophrenia.

Section snippets

Attention as Input Selection

In the most famous definition of attention, William James wrote:

Everyone knows what attention is. It is the taking possession by the mind, in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought. Focalization, concentration, of consciousness are of its essence. It implies withdrawal from some things in order to deal effectively with others . . . (reference 3; pp. 381–382)

This remains the canonical definition of attention among cognitive

Distinguishing Among Attention, Executive Control, and Working Memory

There is a great deal of overlap between conceptions of and research on the broad constructs of attention, executive control, and working memory. This partly reflects the extensive interactions between these broad constructs in most cognitive tasks, and it partly reflects imprecision and inconsistency in the usage of these terms. However, these terms refer to constructs that can and should be distinguished.

Control and Implementation of Selection

As discussed in the preceding text, executive processes send control parameters to the input selection system that determine what types of inputs should be selected. These parameters will cause attention to be focused onto a given input, which in turn causes a facilitation of processing for the attended input and an inhibition of processing for the unattended inputs. One set of processes is used to identify the input that should be selected, and another set of processes is used to produce

Selective Disruption of Attentional Control in Schizophrenia

Although control and implementation can be difficult to isolate experimentally, the available evidence suggests that schizophrenia involves a deficit in the control of selection but not in the implementation of selection. The evidence for this proposal comes from tasks that stress one of these factors while making the other factor trivially easy. We will begin by discussing studies that assess the implementation of selection by making control very easy, and then we will turn to studies that

Conclusions

Almost any task can be considered an attention task, and making sense of the pattern of impairment across tasks can be challenging. We have suggested two main ways of subdividing the broad construct of attention that might be helpful in understanding patient performance. First, we have noted that attention can be used to select between different inputs or to select between different rules. Second, we have made a distinction between the control of selection and the implementation of selection.

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ReviewThe Construct of Attention in Schizophrenia

Section snippets

Attention as Input Selection

Distinguishing Among Attention, Executive Control, and Working Memory

Control and Implementation of Selection

Selective Disruption of Attentional Control in Schizophrenia

Conclusions

Vision Res

Curr Opin Neurobiol

Psychiatry Res

Neuropsychologia

Neuropsychologia

J Psychiatr Res

Schizophr Res

Schizophr Res

Biol Psychiatry

Prog Neuropsychopharmacol Biol Psychiatry

Schizophr Res

Schizophr Res

Schizophr Res

Cognit Psychol

Neuropsychologia

Schizophr Res

Dementia Praecox or the Group of Schizophrenias

Dementia Praecox and Paraphrenia

The Principles of Psychology

Attention

Neural mechanisms of selective visual attention

Annu Rev Neurosci

Mechanisms of visual-spatial attention: Resource allocation or uncertainty reduction?

J Exp Psychol Hum Percept Perform

Selective attention gates visual processing in the extrastriate cortex

Science

Neural mechanisms of spatial selective attention in areas V1, V2, and V4 of macaque visual cortex

J Neurophysiol

Competitive mechanisms subserve attention in macaque areas V2 and V4

J Neurosci

Density effects in conjunction search: Evidence for a coarse location mechanism of feature integration

J Exp Psychol Hum Percept Perform

Electrophysiological evidence for a postperceptual locus of suppression during the attentional blink

J Exp Psychol Hum Percept Perform

Dual-task interference in simple tasks: Data and theory

Psychol Bull

Review
The Construct of Attention in Schizophrenia