Cognitive Recovery and Rehabilitation After Brain Injury: Mechanisms, Challenges and Support

Prefrontal cortex and hippocampus in behavioural flexibility and posttraumatic functional recovery: Reversal learning and set-shifting in rats

“…During functional recovery, these two structures are mutually dependent regarding reversal learning, but not regarding set-shifting. This differentiation between the neural substrates of reversal learning and set-shifting, respectively, is in agreement with the predictions of our model of Reorganization of Elementary Functions (the REF-model) [Mogensen, 2011a[Mogensen, , 2011b[Mogensen, , 2012a[Mogensen, , 2012b[Mogensen, , 2014[Mogensen, , 2015Mogensen and Malá, 2009]. M a n u s c r i p t M a n u s c r i p t M a n u s c r i p t M a n u s c r i p t M a n u s c r i p t M a n u s c r i p t…”

“…In that case, the asymptomatic performance of the two groups with individual lesions could be explained in terms of a shift towards an alternative neural substrate that efficiently masked the impairment created by the prefrontal lesion. We have previously argued [Mogensen, 2011a[Mogensen, , 2011b[Mogensen, , 2012a[Mogensen, , 2012b[Mogensen, , 2014[Mogensen, , 2015Mogensen and Malá, 2009] that posttraumatically, the neural substrate of task mediation is reorganized in such ways that within the preserved regions of the brain a given structure can demonstrate either an increased or decreased contribution to the mediation of the task. In support of that, we have reported findings suggesting that during posttraumatic recovery of task performance on certain tasks, there is a mutual interdependence between the prefrontal cortex and the hippocampus [Mogensen et al, 2004a[Mogensen et al, , 2005[Mogensen et al, , 2007.…”

Reorganization of the Connectivity between Elementary Functions – A Model Relating Conscious States to Neural Connections

“…(A) A surface phenomenon such as task performance or conscious representations may before and after injury, respectively, be mediated by dissimilar neural substrates and computational processes – although the surface phenomena superficially viewed are similar (e.g., demonstrating task performance of similar proficiency). Furthermore, (B) contributions to task mediation provided by individual substructures appear to be of a “modular” nature – contributing information processing which is not task-specific – or for that matter specific to any of the cognitive domains – but rather contributes the same type of analysis within a multitude of different contexts/tasks ( Mogensen and Malá, 2009 ; Mogensen, 2011a , c , 2012a , b , 2014 , 2015 ).…”

“…And a “higher” level of hypercomputations – a level at which mental representations are mediated by a connectionist network combining the specific modules of the previous level (see Figure 1 ). We have developed such a novel approach to the construction of a computational level and an alternative understanding of modularity (e.g., Mogensen and Malá, 2009 ; Mogensen, 2011a , c , 2012a , b , 2014 , 2015 ; Overgaard and Mogensen, 2011 , 2014 , 2015 ).…”

“…Attempting to establish a comprehensive model of the neural and cognitive mechanisms of posttraumatic functional recovery of problem solving, the REF model was constructed ( Mogensen and Malá, 2009 ; Mogensen, 2011a , c , 2012a , b , 2014 , 2015 ). The REF model essentially describes a connectionist network in which, however, the “unit” is not a neutral and functionally “indifferent” “neuron” – but advanced information processing modules called elementary functions (EFs).…”