Thalamus wakes the brain during development

Consciousness requires continuous, internally generated activity in the brain. The modulation of this activity is the basis of the electroencephalogram (EEG) and of generation of sleep, dreams, and perception. Achieving such activity is thus an important milestone in normal brain maturation, which occurs around birth. Successful transition to this activity indicates a good prognosis for babies born prematurely and/or suffering from damage to the brain.

To be functional as a dreaming, seeing, and thinking entity the brain need to achieve two milestones: continuity, which means that the brain is always active and state dependence, meaning brain activity is modulated by sleep, waking, and attention. The circuit mechanisms behind the development of continuity and state dependence in the brain have remained unknown, but have been widely assumed to be located in the cerebral cortex, the convoluted brain structure responsible for thought and perception.

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