The development and improvement of neuroimaging techniques over the last few decades has made it possible to understand the structures and functions of the brain in living subjects. Before the appearance of these techniques, the study of the brain was considerably limited, so that it was difficult to identify the changes that took place in it over time.

The emergence of neuroimaging techniques

Neuroimaging has opened up new lines of research , such as the identification of abnormalities in the brain function of subjects with psychiatric pathologies, determination of the brain structures involved during the performance of a specific task (such as remembering a list of names) – or a better understanding of the brain mechanisms involved in the escape response.

A way to objectively measure the effectiveness of psychological therapy

Psychological therapy produces changes in a patient’s emotional state, belief system, and behavior. Therefore, it is not strange that these changes also occur at the brain level . One of the lines of research that has been developed with the arrival of neuroimaging is the study of the brain changes that are produced as a consequence of psychological therapy.

Before the advent of neuroimaging, the effectiveness of psychological therapy was measured based on subjective measures such as patient and therapist assessment of the degree of improvement achieved or comparison of the results of pre- and post-treatment tests. However, the neural substrate of such improvement was unknown. Hence, the brain was compared to a black box whose contents could not be known. The advent of neuroscience and, more specifically, of neuroimaging, made it possible to open this box and begin to understand the functioning of the most complex organ in the body.

Changes in the mind produce changes in the brain

If we can now see the functioning and the transformations that take place in the brain, it becomes possible to measure objectively the changes that occur during the course of psychological treatment , and also those that may occur after the completion of therapy. This advance makes it possible to identify those psychological treatments that are most effective for a given disorder. The brain, being a plastic organ, is shaped as a consequence of the experiences that the subject has and responds to psychological treatment through changes in its structure and functions.

Barsaglini et al. (2014) conducted a review of the main research that has analysed the effects of psychological therapy on patients with mental disorder. In this review they found that obsessive compulsive disorder is characterised by hypermetabolism of different areas of the brain, including the caudate nucleus . Many studies point out that cognitive-behavioral treatments in patients with obsessive-compulsive disorder produce a “normalization” of the metabolic levels of the caudate nucleus and that this “normalization” is accompanied by an improvement in the symptoms.

On the other hand, patients with specific phobias (such as spider phobia) experience a reduction in the activity of the limbic system involved in the fear response as a result of having participated in cognitive-behavior-oriented psychological therapy. In the case of patients with schizophrenia, several studies collected in the review by Barsaglini et al. observe that psychological therapy produces a normalization of the pattern of activity in the fronto-cortical areas and, therefore, an improvement in the symptoms.

Towards a design of effective psychological treatments based on neurobiological evidence

In general terms, these results indicate that psychological therapy produces changes in the functioning of the brain and that these changes are associated with an improvement in the patient’s symptoms . In this sense, although to different degrees depending on the disorder in question, both pharmacological and psychological therapy allow the normalization or compensation of abnormal patterns of brain activity.

Although it is still early to draw consistent conclusions (there are divergences in the scientific literature about what specific brain changes psychological therapy produces and also about which methodology is most suitable for measuring such changes), neuroimaging opens the door to a promising line of research: the design of effective psychological treatments based on neurobiological evidence .

Biliographic references:

  • Barsaglini A, Sartori G, Benetti S, Pettersson-Yeo W and Mechelli A. (2014). The effects of psychotherapy on brain function: A systematic and critical review. Progress in Neurobiology, 1-14.