Tunnel vision: what is it and what are its causes?

Tunnel vision is a peculiar phenomenon that affects the ability to perceive stimuli from our environment. It is relatively frequent that, when we are in a marked state of psychophysiological stress, we pay attention exclusively to what is related to the task, threat or main concern that we occupies.

In this article we will describe what is tunnel vision and what are its causes. In order to do so, we will do a brief review of the cognitive theory on the different modalities of attention, and We will explain the difference between the concept of tunnel vision that we handle in psychology with the use that is made of it in Medicine.

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Attention as a physiological activation

Attention is a broad psychological function, and as such the alterations that affect it can give rise to very diverse phenomena. Thus, for example, if we pay attention to attention as the ability to select a stimulus and focus our cognitive resources in it, we can identify disorders of this function in schizophrenia or in episodes maniacs.

They have also been described attention-related disturbances such as concentration (such as mental absence and time gap), as vigilance (which in generalized anxiety disorder has the character of 'Hypervigilance'), as expectations (a relevant aspect in psychosis) and as physiological activation, associated with the experience of stress.

The phenomenon of tunnel vision is part of this last field of analysis of attentional processes. However, it is an ambiguous concept that has not been used only in the field of psychology, but there has also been talk of tunnel vision in medical contexts, particularly in that of ophthalmology.

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What is tunnel vision?

From the point of view of cognitive psychology, tunnel vision is an alteration of attention that occurs in situations of intense stress, particularly when experiencing a sense of threat. However, this does not always correspond to reality, but some individuals are more prone than others to tunnel vision.

Specifically, it has been proposed that introverts have a greater tendency than extroverts to tunnel vision, if we understand these two constructs as defined by Eysenck: as manifestations of the base level of activation of the cortex cerebral. Thus, introverts are more prone to this phenomenon due to their higher level of general anxiety.

Tunnel vision is also less common in children and the elderly than in people of intermediate age; this is also due to differences in cortical activation. On the other hand, of course, the experience of situations that are objectively threatening for a given person they increase the probability of tunnel vision.

In the general medical context, the term "tunnel vision" is commonly used to refer to the loss of peripheral vision, as occurs in glaucoma. People with this disorder can only see clearly the central part of their visual field; from this derives the perception of it with the approximate shape of a tunnel.

Nevertheless, in the psychology of attention the term has a more abstract character; many experts not only include visual disturbances caused by stress within it, Rather, the narrowing of attention to which it is due can affect others in the same way. senses. Noteworthy is hearing, almost as important as sight for humans.

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Causes of this phenomenon

Tunnel vision understood as an attentional phenomenon is due to specific hypervigilance, that is, selective attention to stimuli that are associated with a potential threat to safety or survival. This makes it easier for us to attend to the stimuli that we consider relevant, but it reduces the ability to perceive the rest of the factors in the situation.

Cortical activation is highly dependent on the release into the bloodstream of stress hormones, the most important of which are corticosteroids. This occurs in a more marked way, the greater the perception of stress of the person, the more intense the physical and mental activity carried out and the more demanding the demands of the situation.

Many cognitivist models of attention focus on the fact that our attentional resources are limited, so we can only focus our perception on one or the other stimuli dividing these in different ways capabilities. In this sense, it is relevant to remember that there is various types of attention: selective, focused, divided ...

When tunnel vision takes place, our eyesight, and frequently also the rest of the senses, focus only on the stimuli that we associate with what worries us the most. This leads to a very marked reduction in our probability of adequately perceiving the rest of the stimuli, reducing the quality of our behavior.