PS263 Chapter Notes - Chapter 8: Temporal Lobe, Visual Cortex, Basal Forebrain
Document Summary
A cut through the midbrain decreases arousal by damaging the reticular formation. Part of reticular formation and contributes to cortical arousal. Neurons receive input from sensory systems and generate spontaneous activity of their own. Axons extend into forebrain and release acetylcholine and glutamate which excite cells in hypothalamus, thalamus and basal forebrain. Maintains arousal during wakefulness and increases it in response to new or challenging tasks. Small structure in the pons, usually inactive (esp during sleep) Emits bursts of impulses in response to meaningful events, esp emotional ones. Axons release norepinephrine throughout cortex, has huge influence. Output increases gain - increases activity of the most active neurons and decreases activity of less active neurons. Results in enhanced attention to important info and enhanced memory. One pathway releases excitatory transmitter histamine which enhances arousal and altertness throughout brain. Another pathway releases peptide neurotransmitter orexin (also called hypocretin) which extend to basal forebrain and enhance wakefulness.
