Friday, 18 March 2016

The Neuroscience of Being 'Us';Part 1 The cortex and emotion

The region of the brain called the prefrontal cortex (PFC) is really what defines us as human; it is crucial for how we pay attention, it enables us to put things in the ‘front of our mind’ and hold them in awareness. It is the basis of our moral system and capacity for empathy. Studies of people who have suffered injury to the PFC show us that it is an important brain area for creating our ‘map of the world’ i.e. the mental representation of our outer experience. Various different parts of the cortex have specific functions:

The Pre-Frontal Cortex (PFC) regions in the two hemispheres

  • The Medial Pre-frontal Cortex (MPFC) is the integration centre involved in coordinating left and right sides with direct connections to the amygdala in the limbic system. This part is involved in our sense of curiosity and awareness and is the part that we target in therapy particularly for dissociated clients who have lost connection with their bodily self. It is activated during mindfulness meditation, mindful awareness or psychotherapy.
  • The Dorso-lateral Pre-frontal cortex (DPFC) is the site of our short-term or working memory and has no direct connection with the limbic system. It is the last bit to develop in the human and often the first to go with ageing. We’ve all had the experience of walking into a room and forgetting why we went there – this is a failure of this part of the brain to hold the requisite information for long enough for us to commit it to longer term memory.
  • The Right Orbital Pre-frontal cortex (ROPFC) (so called because it is directly behind the right orbit of the eye) is most specifically concerned with emotions and arousal regulation as it has good connections with the limbic system and can inhibit activation (this is important in trauma therapy). It develops early in life and is the social centre of the brain, which, if given support and trusting relationships in those early years, becomes more capable of regulating emotion but it depends on good parental attachment (Shore, 2007) . It becomes our 'soothing centre' if promoted by secure attachment. Self-soothing or auto-regulation is very important for subsequent adult emotional regulation. If childhood experience failed to develop this part of the brain a pattern of dysregulated ‘up and down’ or entirely absent emotions results. Our prisons are full of such people where auto-regulation has never been learnt successfully.
Through its links with the limbic system, and the immune system (via regulating levels of cortisol in the HPA axis), the PFC acts as the interface between mind and body and so is implicated in such medically unexplained conditions such as fibromyalgia, whiplash or pelvic pain. These could be construed as the body’s way of expressing emotions through pain; this is termed somatisation. Defined as feeling emotions through the body rather than as feelings, these issues are common in people “in whom emotion is undifferentiated and unregulated” (Shore) . In other words they can’t tell one emotion from another and they may find it difficult to put words to feelings; memories may also be completely dissociated from feelings. This is common after trauma – particularly attachment trauma. The brain gets confused as to what the input represents and may conflate pain with the emotional pain of betrayal/abandonment – they share many of the same pathways.
I met one such person who was on a training course with me. He described some awful events that happened in his childhood without emotion of any kind. He was suffering from this condition, termed alexithymia, (an inability to describe emotions with words) which could be seen as a failure of the ROPFC. Somatisation is not a commonly understood concept in conventional medicine although, in fact, it lies at the base of many of the chronic pain syndromes I am exploring in this book. It is a direct example of how poor relationships and unexpressed emotions make us ill.
The cortex is known to go ‘offline’ in the aftermath of trauma which may explain the sudden switches from hyper to hypo arousal of conditions such as PTSD and other trauma related conditions. As the cortex is normally the modulator of experience, helping to bring logic and a ‘wider view’ its failure to inhibit the limbic system prevents such fine tuning of curiosity and reason. In trauma work we often talk about ‘getting curious’ as the antidote to these limbic states. We need to engage people in what happens when they think a certain thought or act a certain way, enabling them to tune in to their body states – something that they may have actively blocked from childhood onwards. When they begin to look at their reactions as symptoms (i.e. “I've been triggered and this is my survival brain in charge”) and not from an underlying pathology (i.e. I’m mad, bad or weak), they begin to see how extraordinary the human brain is and their curiosity (MFPC-mediated) is aroused . This is a direct antidote to the dissociation and emotional dampening that many people suffer after a traumatic experience. It is the direct target of intervention, whether by linking the two sides of the cortex as in EMDR or by hypnotherapy and CBT whereby we engage the imagination and the thinking brain respectively. We cover these therapies in more detail in my website. Suffice to say no-one need suffer permanently; these states can be reversed as the brain is plastic (neuroplasticity).
This is an extract from my book The Scar the Won't Heal - available now on amazon. In the next instalment I look at Interactions between the cortex and the limbic system.

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