Integrating The Hemispheres: The Divided Brain And Mental Health

Rod Tweedy

This article was written by Rod Tweedy.

Psychotherapy and the divided brain

The relationship between the two hemispheres of the brain is increasingly seen as central to our well-being and mental health, as a number of leading neuroscientists and psychotherapists have observed. Hemispheric imbalances and disconnections underlie many of our most prevalent forms of mental distress and disturbance, including schizophrenia, depression, autism, psychopathy, and alexithymia, as well as many relational and dissociative pathologies, including borderline, narcissistic, schizoid and paranoid personality disorders. A contemporary understanding of the nature of the divided brain is therefore of importance in engaging with and treating these conditions. As Cozolino strikingly observes: “psychotherapy can serve as a means to reintegrate the patient’s disconnected hemispheres”, noting that “the integration of dissociated processing systems is often a central focus of treatment”:

A primary focus of neural integration in traditional talk psychotherapy is between networks of affect and cognition. Dissociation between the two occurs when high levels of stress inhibit or disrupt the brain’s integrative abilities among the left and right cerebral hemispheres as well as among the cortex and limbic regions … Examples from psychiatry and neurology strongly suggest that psychological health is related to the proper balance of activation, inhibition, and integration of systems biased toward the left and right hemispheres. (Cozolino, 2010, p. 110, p. 111, p. 24)

As Cozolino suggests, psychotherapy facilitates neural integration between the cortex and limbic regions, as well as between conscious and unconscious processes, and the networks of affect and cognition, thereby restoring coordination among a number of vital systems where these have been disrupted or damaged. Hemispheric relationship lies at the heart of the therapeutic process itself, as I suggest in my book The Divided Therapist (Routledge, 2020), and a better understanding of the underlying mechanisms that enable integration between the left and right brain will, I believe, help to transform the practice of psychotherapy and psychoanalysis in the twenty-first century. 

One area where a lack of integration between the left and right hemispheres can be particularly devastating is in early relational development. It is the right hemisphere of the brain which is dominant for the first eighteen months of life (Mucci, 2020, Cozolino 2010), and early developmental processes are therefore largely dependent on and rooted in right hemisphere networks of attachment, affect regulation, and implicit sense of self. Damage or impairment to these networks can lead to significant patterns of subsequent disruption and imbalances between the hemispheres, which are often the focus of later psychotherapeutic treatment. As Schore, one of the pioneers in investigating these systems and their impact on our relational well-being, notes, “there is now consensus that deficits in right brain relational processes and resulting affect dysregulation underlie all psychological and psychiatric disorders” (2020, p. 74). “Impaired integration”, observes Siegel, another major figure in our understanding of the role of hemispheric re-integration in the clinical practice of therapy, “is the root of mental dysfunction” (Siegel & Solomon, 2013, p. 2). As Russell Meares remarks, “disintegration is perhaps the central pathology induced by relational trauma. It manifests a failure to develop a co-ordination among the elements of the brain/mind system necessary to the emergence of self” (2020, p. 242). Because of these powerful and compelling associations between impaired integration, hemispheric disconnection, and mental distress, there is increasing awareness that we need to rethink and reframe our understanding of what we actually mean by “mental disorder”. What we currently term “disorders” might in fact be more accurately thought of as “dis-integrations”, since so many forms of distress that we encounter are rooted in forms of hemispheric disorganisation and disruption. According to the most recent neuroscientific and psychoanalytic research, disorder is not so much a breakdown in order as a breakdown in integration.

Integration and Balance 

Integration does not simply mean finding a “balance” between the hemispheres, as if each were two identical and equal players: “The relationship between the hemispheres,” McGilchrist observes, “is not symmetrical. Each needs the other; each has an important role to play. But those roles are not equal – one depends more on the other, and needs to be aware of that fact”:

One hemisphere, the right hemisphere, has precedence, in that it underwrites the knowledge of that the other comes to have, and is alone able to synthesise what both know into a usable whole. (McGilchrist, 2009, p. 176)

The right hemisphere, he notes, has precedence not only in terms of “primacy of experience”, but also in terms of “primacy of wholeness”, “the primacy of the implicit”, “primacy of broad vigilant attention”, “primacy of affect”, and “primacy of the unconscious will” (McGilchrist, 2009, pp. 176-208). It is the hemisphere that grounds us and sustains us when we start breathing, the hemisphere that underwrites the first eighteen months of our life and our earliest developmental formations, it is the hemisphere that supports and delivers every relationship, attachment, and embodied experience we have (as “the seat of our unconscious, our embodiment and emotional regulation”, as Dowds notes), and it is the hemisphere that empathises with our final breath. The right hemisphere underwrites and “delivers” our direct experience of the world, which the left brain then “unpacks” and processes, before returning it to the right hemisphere, to be re-integrated into the wider picture. As Dowds notes in her compelling discussion of this process:

McGilchrist argues—by analogy to the Hegelian triad of thesis, antithesis, and synthesis—that complete and rich processing of experience requires a sequence of transfers between the hemispheres in the following order: right, left, and then right again. This entails: holistic experiencing by the right brain; logical examination and categorisation by the left; and then a return to the right for a final synthesis of the original gestalt with the abstract analysis, so as to generate an integrated and transformed whole that is more than the sum of its parts. (Dowds, 2014, pp. 71-72)

This is the process that therefore underlies and underwrites integration: right-left-right (‘R-L-R’). It also underwrites the integrative form of group therapy developed by Gantt and Badenoch, known as ‘Systems-Centered Therapy’ (SCT), which also draws on McGilchrist’s groundbreaking work in this field: “SCT’s theory uses a left brain map to access greater right brain knowing and integration, again a flow of R-L-R”, thereby facilitating and nurturing “a group mind that supports right brain function and right-left-right hemispheric integration”. They call this movement “the ongoing collaboration of right-left-right, which is our brain’s natural pattern of development and transformation”, and again link it to McGilchrist’s work in understanding the relationship between the ‘master’ hemisphere and the ‘emissary’. In other words, first psycho-analysis, and then psycho-synthesis (“the emissary reporting back to the Master, who alone can see the broader picture”, McGilchrist, 2018, p. 25).

“The work of the left hemisphere needs to be integrated with that of the right hemisphere”, notes McGilchrist (2009, p. 131, italics in original). He eloquently argues “that the rationality of the left hemisphere must be resubmitted to, and subject to, the broader contextualising influence of the right hemisphere, with all its emotional complexity” and “that the rational workings of the left hemisphere … should be subject to the intuitive wisdom of the right hemisphere” (ibid., p. 203). What the left hemisphere offers, brilliantly, and uniquely, is “a valuable, but intermediate process, one of ‘unpacking’ what is there and handing it back to the right hemisphere, where it can once more be integrated into the experiential whole” (McGilchrist). What the left hemisphere delivers, then, is dissection, analysis, separation. What the right brain delivers is wholeness, and in this again it has a peculiar resonance and relationship with therapy. For the whole purpose of therapy is wholeness – the very word “health” (as in “mental health”) means wholeness (O.E. hælan, “to make whole, sound and well”). And wholeness is the result of integration: “healing emerges from integration”, note Siegel and Solomon, again pointing to the intimate connections between healing, health, and wholeness (Siegel & Solomon, 2013, p. 7). The result of all this all this knowing thyself, all these examined and unexamined lives, all this distress and division and dysfunction – is integration.

It is this integration that emerges within us and between us that frees the mind from its suffering in isolation, its repeated states of chaos and rigidity that emerge from an unintegrated life. (ibid., Siegel & Solomon, 2013, p. 8, p. 268) 

How do you know if you’re integrated? “The outcome of integration”, notes Siegel, “is kindness and compassion”. Kindness is a state which is not judgmental, competitive, or instrumental. These are signs and symptoms of an inner disconnection, an obstacle, a dis-organisation or dis-harmony. “From this perspective mental illness results from a disconnection from others and a retreat into selfishness”, notes Cozolino (2006, p. 414). And if, as Cozolino strikingly suggests, mental illness is the result of separation from others, from disconnection and lack of integration, then mental health is the emergence into interconnection, into interdependency, into wholeness. Into kindness. 


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