Neocortical Override

a form of ‘cortical override’ mechanism may be useful. If there has been excessive parcellation (pruning) of corticolimbic structures, then the brain’s ability to monitor and modify states of arousal may be quite compromised.

Siegel identifies cortical override as a conditionally valuable mechanism while warning that trauma-induced pruning of corticolimbic structures may render it inaccessible in the populations who most require it.

Siegel, Daniel J., The Developing Mind: How Relationships and the Brain Interact to Shape Who We Are, 2020thesis

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bottom-up ‘hijacking’ by the subcortical brains (Goleman, 1995) results in the loss of neocortical monitor

Ogden frames the clinical problem as subcortical hijacking that structurally forecloses neocortical monitoring, explaining why top-down cognitive override strategies fail traumatized clients.

Ogden, Pat, Sensorimotor Psychotherapy Interventions for Trauma and, 2015thesis

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Clients who try unsuccessfully to use top-down management skills to regulate their emotions or physical responses—such as trying to convince themselves they are not in danger or should not feel the way they do—will find an explanation of why such self-talk may be ineffective.

Ogden provides a psychoeducational rationale for why neocortical override via self-talk is unreliable, grounding the limitation in the structural architecture of the three-brain model.

Ogden, Pat, Sensorimotor Psychotherapy Interventions for Trauma and, 2015supporting

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a particular level may override the others, depending on the environmental conditions. Even when one level supercedes the others, however, cognitive, emotional, and sensorimotor processing are functionally mutually dependent and intertwined

Ogden establishes that override is bidirectional and context-dependent across hierarchical brain levels, undermining any simple neocortical supremacy model.

Ogden, Pat, Trauma and the Body: A Sensorimotor Approach to Psychotherapy, 2006supporting

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the mere removal of the neocortex does not lead to major deficits in instinctual behaviors, although such animals are certainly not very bright.

Panksepp challenges the assumption of neocortical primacy by demonstrating that organized instinctual and emotional behavior persists in decorticate animals, relativizing the override model evolutionarily.

Panksepp, Jaak, Affective Neuroscience The Foundations of Human and Animal, 1998supporting

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comparable neocortical damage in humans has severe motor effects, namely paralysis, suggesting that adult human brain functions are more dependent on neocortical functions than the brains of lower mammals.

Panksepp qualifies his decortication argument by noting that adult humans have become developmentally dependent on neocortical function in ways lower mammals have not, lending partial support to the override concept.

Panksepp, Jaak, Affective Neuroscience The Foundations of Human and Animal, 1998supporting

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Early alteration of the circuits and epigenetic regulation of specific regions of the brain involved in the stress response and in evaluative processes can deeply influence the appraisal mechanisms that directly influence emotional experience and its regulation.

Siegel argues that early trauma epigenetically degrades the very cortical appraisal circuits upon which neocortical override would depend, establishing a developmental ceiling on its clinical applicability.

Siegel, Daniel J., The Developing Mind: How Relationships and the Brain Interact to Shape Who We Are, 2020supporting

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the relationship between the cortex – the outermost layer, literally the ‘shell’, of the brain – and the regions which lie below it

McGilchrist’s opponent-processor model contextualizes the cortex-subcortex relationship as one of dynamic complementarity rather than hierarchical override, implicitly critiquing unidirectional cortical control models.

McGilchrist, Iain, The Matter With Things: Our Brains, Our Delusions and the Unmaking of the World, 2021aside

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the thalamic-neocortical axis—stream of thought) information processing. They converge on the reptilian brain, or basal ganglia.

Panksepp’s somatic-visceral processing schema situates the neocortical stream as one of two converging axes at the basal ganglia, framing cortical override as partial rather than total modulation.

Panksepp, Jaak, Affective Neuroscience The Foundations of Human and Animal, 1998aside

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