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Jakob Hohwy seeks to recover an approach to consciousness from a general theory of brain function, namely the prediction error minimization theory. The way this theory applies to mental and developmental disorder demonstrates its relevance to consciousness. The resulting view is discussed in relation to a contemporary theory of consciousness, namely, the idea that conscious perception depends on Bayesian metacognition which is also supported by considerations of psychopathology. This Bayesian theory is first disconnected from the higher-order thought theory, and then, via a prediction error conception of action, connected instead to the global workspace theory. Considerations of mental and developmental disorder therefore show that a very general theory of brain function is relevant to explaining the structure of conscious perception. Furthermore, Hohwy argues that this theory can unify two contemporary approaches to consciousness in a move that seeks to elucidate the fundamental mechanism for the selection of representational content into consciousness.

Chapter 9 proposes a conceptual framework for describing instances of thinking, self-reflection, and metacognition in dreams and analyzes their relationship to insight and control in lucid dreams. It also discusses the question of whether dreams involve beliefs. A preliminary result is that existing hypotheses that cast dreaming as a state of cognitive deficiency in which the phenomenology of being a rational, thinking self and cognitive agent is almost completely absent are oversimplified. Instead, dreaming in general, and not just lucid dreaming, involves various forms of conscious thought and metacognitive activity. What is interesting and unique about dreaming is not the absence of conscious thought but the close relationship in which it stands to lower-level, automatically generated imagistic cognition.

Pediatric traumatic brain injury (TBI) is a major health concern, with an annual incidence of 400 in 100,000 and it is the major cause of disability and death in children in the United States (Langlois, Rutland-Brown, and Thomas 2005). The Glasgow Coma Scale (GCS) (Teasdale and Jennett 1974) is a standard measure of severity of impaired consciousness, and it is used as a measure of TBI severity. Mild TBI is generally defined by the lowest post-resuscitation GCS score of 13–15, but many investigators have also stipulated that a mild TBI is defined by a normal computed tomographic (CT) scan within 24 hours after injury or at least no CT evidence of a brain lesion. Moderate injury has a GCS score of 9–12 or a score of 13–15 with an intracranial lesion. Severe injury has a GCS score of 8 or lower, consistent with coma. The pathology of TBI can be classified into diffuse and focal brain injury, although both types of injury can coexist in the same patient. Focal brain injury is characterized by mechanical forces that produce localized primary lesions that occur at the moment of trauma, such as cortical contusions. In closed head injuries, these forces can also produce hemorrhage in the epidural, subdural, subarachnoid, or intracerebral compartments of the cranium. Diffuse brain injury, more common in children than in adults with severe TBI, is caused by rapid movement of the head due to acceleration, deceleration, and rotational forces, which causes primary axonal injury, such as axonal stretch and shearing. Occurring immediately after trauma and producing effects that may progress over time, secondary injuries include ischemia, brain swelling, breakdown of the blood- brain barrier, release of excitatory neurotransmitters, generation of free radicals, cellular death and dysfunction, hypoxemia, and seizures. Hypotension is a serious complication of TBI and a challenge for acute neurocritical care (Kochanek 2006).

My children have never looked much like those described in most theories of cognitive development. I don’t mean that they are generally deviant or that they perform abnormally on conservation or class inclusion tasks. They generally seem more or less normal, and on the few occasions when I have presented tasks from the cognitive developmental literature, they have acted pretty much like the children described in the articles. Where my children are altogether different from the theoretical descriptions is in the variability of their thinking. Cognitive developmental theories generally depict age and thought as proceeding in a 1:1 relation. At an early age, children think in one way; at a later age, they think in another way; at a still later age, they think in a third way. Such descriptions are so pervasive that they begin to feel like reality. Young children are said to form thematic concepts; somewhat older ones to form chain concepts; yet older ones to form true concepts. The reasoning of young children is said to be preoperational; that of somewhat older ones concrete operational; that of yet older ones formal operational. Young children are said to have one theory of mind; somewhat older ones a different, more inclusive theory; yet older ones a more advanced theory still. The story is the same with characterizations of performance on specific tasks. In descriptions of the development of the concept of living things, 3- and 4-yearolds are said to think that anything that moves is alive, 5- to 8-year-olds that animals—and only animals—are alive, and older children that plants as well as animals are alive. In descriptions of the development of addition skill, kindergartners are said to count from one; first through third graders to count from the larger addend; fourth graders and older children to retrieve answers from memory. In descriptions of the development of serial recall strategies, 5-year-olds are said not to rehearse; 8-year-olds to rehearse in a simple way; 11-year-olds to rehearse in a more elaborate way. My children’s thinking has never looked as neat and clean as these 1:1 characterizations of the relation between age and thought.