Evidence for Psychotherapy


Psychotherapy is supported by neuroscientific principles

For a long time it was thought that ‘serious’ treatment of psychological problems required medication, and that psychotherapies (particularly psychoanalysis, the original ‘talking cure’) could not in themselves alter character or affect the brain. But the advent of neuroscience has changed this assessment (Doidge, 2007:218). Realisation that the brain is malleable and ‘plastic’ rather than hard-wired and fixed (i.e. that its structure and function change with different experiences, and that contrary to longstanding belief, new neurons can grow) has radically expanded the possibilities for learning, healing and change. It has also led to major reappraisal of the effectiveness of psychotherapy.

Increasingly, psychotherapy is seen not only as compatible with neuroscientific principles, but as convergent with them (Cozolino, 2002; Doidge, 2007). In fact the issues and problems which are addressed in psychotherapy have their physiological correlate in compromised neurological functioning  – ‘When one or more neural networks necessary for operational functioning is underdeveloped, underregulated, or underintegrated with other networks, we experience the complaints and symptoms for which people seek psychotherapy’ (Cozolino, 2002:16).

To the extent that the brain is malleable rather than ‘fixed’, its very structure is now recognised to be influenced in an ongoing way by social, cultural and relational dynamics. This means that psychotherapy presents valuable opportunities for integration and healing. In providing ‘an enriched environment that promotes the development of cognitive, emotional, and behavioural abilities’ (Cozolino, 2002:23) psychotherapy is now shown to correlate with detectable changes in the brain.

Why and how is psychotherapy effective?

How, though, does psychotherapy work not only to enhance emotional well-being, but to ‘re-integrate’ disrupted neural connections? What is now termed ‘the social brain’ is built over time. Early experience with care-givers is crucial, endures into adult life, and significantly shapes our experience of it (‘the organization of the social brain is initially sculptured by parent-child interractions’; Cozolino, 2002:217).  But the emotional (‘attachment’) patterns of our early years can also be worked with and modified; a task which is the ‘stuff’ of psychotherapy.

The process of ‘working through’ previous experiences (which are crucially shaped by our interractions with early care-givers and significant others) is sometimes described as ‘earned security’. Adult ability to experience well-being is determined not by negative influences per se, but by the extent to which we are able to come to terms with, and thereby ‘resolve’ them – ‘Studies have shown that individuals can move from what was an insecure childhood attachment to a secure adult attachment status’ (Siegel, 2004:123). Previous negative experiences can be integrated later in life, which is precisely what psychotherapy aims to assist.

The importance of key neurotransmitters to psychological health and emotional well-being is increasingly understood. In the frontal cortex, the neurotransmitters of serotonin, dopamine and norepinephrine are stimulated by positive experiences and social interractions (Cozolino, 2002:316).  In the ‘enriched’ environment of psychotherapy, as Cozolino describes, there are multiple opportunities for neurotransmitters central to the experience of well-being to be stimulated in positive ways.  This also accounts for his contention  that ‘all forms of psychotherapy – from psychoanalytic to behavioural interventions…are successful to the extent that they enhance change in relevant neural circuits’ (Cozolino, 2002:xiv).

For people who simply want to ‘feel better’, neuroscientific validation of the effectiveness of psychotherapy (via imaging which correlates observable changes in the brain) may be of little interest. ‘Subjective’ measures and client testimony might seem to be enough. Scientific confirmation is, after all, only one measure of effectiveness (and with respect to experiences of well-being, not necessarily the most important). But to the extent that we live in a society in which scientific findings are authoritative – and claims for ‘evidence-based’ treatment assume the centrality of scientific method – neuroscientific evidence is both important and validating.

In this context, the key point is the extent to which neuroscientific research supports the process of psychotherapy per se. Not only does psychotherapy furnish a safe environment (the whole purpose of which is to facilitate healing). The degree to which experience of psychotherapy can assist the realignment of disrupted neural pathways can now be shown to register in the brain.

Neuroplasticity accounts for both mental flexibility and mental rigidity (Doidge, 2007:244). But new understanding of brain functioning (i.e. as malleable rather than fixed) also suggests that we may have underestimated our capacity for flexibility, healing and change:

Today we have the clinical tools to repair deeply embedded
and disrupted neural networks. It’s an exciting time for the
practice of psychotherapy (Neborsky, 2003: 319).

What about evidence for specific types of therapy?

The range and variety of contemporary psychotherapies means that there are many ways of working, and many paths to reintegration. For example, at a very broad level psychodynamic approaches emphasise insight, humanistic orientations focus on self-acceptance and cognitive behavioural therapy is concerned with the influence of thoughts on behaviour (McLeod, 1999:8). A popular contemporary approach is that of narrative therapy, which addresses the ‘stories’ we tell ourselves about our issues and lives. There are numerous modalities and ways of working on offer, and there is no ‘one size fits all’.

A key point, as noted above, is the capacity of the process of psychotherapy per se to assist healing which can be both subjectively experienced (feeling better, functioning in a more integrated way) and objectively correlated (neuroscientific observation of  neural realignment and change). For this reason, Cozolino (2002:27) contends that ‘all forms of therapy, regardless of theoretical orientation, will be successful to the degree to which they foster neural growth and integration’. But the variety of the field of psychotherapy also invites questions about the efficacy of particular approaches and modalities. Such questions are often of particular interest when it comes to choosing a therapist.

As regards the evidence-base for specific varieties of psychotherapy, this varies according to the particular modality and approach. Absence or paucity of research into a variety of therapy does not of itself mean that the approach ‘doesn’t work’. It can simply mean that research into its specific and characteristic features may not have been carried out. This is an important point to understand in a culture in which ‘lack of evidence’ (and particularly scientific evidence) can wrongly imply ineffectiveness.

As an activity of clinical practice, research is not the highest priority of many competent and skilled practising therapists. It is also the case that rapid expansion of the profession of psychotherapy as a whole means that it is only relatively recently that concerted steps are being taken to formally research the effectiveness of the range of approaches available. As well as being time-consuming, quality research requires resources which are not always readily accessible.

For example, the approach of cognitive behavioural therapy (CBT) is widely cited as effective on the basis of the research conducted into it. But research into the effectiveness of CBT has also been heavily funded in ways that other approaches have not. It is likely that evidence for the effectiveness of other therapeutic approaches will increasingly emerge as research into the various approaches is increasingly conducted. In this context it is also important to reiterate that ‘effectiveness’ can itself be assessed in a variety of ways.

These points notwithstanding, it is significant that some major findings about effectiveness have emerged from studies conducted within the field. Particularly interesting is the now considerable research which attests that the particular variety of psychotherapy employed is only one measure of its effectiveness, and not necessarily the most significant. What is now widely referred to as ‘common factors’ research (Duncan, Miller, Wampold & Hubble, 2010) shows that such dimensions as client (‘extra-therapeutic’) factors  and the quality of the therapeutic alliance are more reliable determinants of effective therapy than the approach or technique deployed.

Research into diverse modalities of psychotherapy continues (and is now growing apace).But both the substantiated effectiveness of psychotherapy per se (see earlier discussion) and the respected research which has found ‘equivalent effectiveness’ of otherwise diverse modalities are important findings in themselves. In combination, they suggest that the effectiveness of the variety of psychotherapy you experience may be determined less by particular modality and specific technique than by shared features of psychotherapy per se and personal receptivity to the approach being offered.

An important preliminary safeguard when looking for a counsellor relates not only to formal qualifications, but to current membership of a professional body. Checking to confirm that the therapist you elect to see is a fully qualified and registered member of the relevant professional organisation (which may vary according to training and approach) and ideally a member of the relevant ‘umbrella’ state and/or national counselling and psychotherapy body, is your best guarantee of reputable, ethical and effective practice.


Cozolino, Louis  The Neuroscience of Psychotherapy: Building and Rebuilding the Human Brain (New York: Norton, 2002).
Doidge, Norman [2007]The Brain that Changes Itself: Stories of Personal Triumph from the Frontiers of Brain Science (Melbourne: Scribe, 2008).
Duncan, B., Miller, S. & Wampold, B. & Hubble, M., eds. The Heart and Soul of Change: Delivering What Works in Therapy, 2nd edit. (Washington, DC: American Psychological Association, 2010).
King, Robert ‘What’s New in Psychotherapy Research?’ Conference Report, Psychotherapy in Australia (Vol.16, No.2, February 2010), pp.18-20.
King, Robert , ‘What’s New in Psychotherapy Research?’ Conference Report, Psychotherapy in Australia (Vol.16, No.4, August 2010), pp.34-37.
McLeod, J. (1999) An Introduction to Counselling (Buckingham: Open University Press).
Neborsky, R.J. (2003) ‘A Clinical Model for the Comprehensive Treatment of Trauma Using an Affect Experiencing-Attachment Theory Approach’, in Solomon, M.F. & Siegel, D.J., ed. Healing Trauma. New York: Norton, pp.282-321.
Schore, Allan Affect Dysregulation and Disorders of the Self (New York: Norton, 2003).
Siegel, Daniel J. The Developing Mind: How Relationships and the Brain Interact to Shape Who We Are (New York: The Guilford Press, 1999).
Siegel, Daniel J. & Hartzell, Mary Parenting from the Inside Out: How a Deeper Understanding Can Help You Raise Children Who Thrive (New York: Penguin, 2004).