The Human Neural System:
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Complex network of specialized cells.
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Controls and coordinates bodily functions.
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Responds to various stimuli.
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Maintains internal balance.
The Midbrain:
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Part of the brainstem.
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Involved in sensory processing, especially visual and auditory.
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Role in motor control and regulation of sleep-wake cycles.
Reflex Action and the Reflex Arc:
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Rapid, involuntary responses to stimuli.
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Involves sensory receptor, sensory neuron, interneuron, motor neuron, and effector organ.
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Allows quick responses without conscious thought.
Peripheral Nervous System (PNS):
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Outside the central nervous system (CNS).
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Transmits sensory information to the CNS.
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Carries motor signals from the CNS to effectors.
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Communication network.
Autonomic Neural System (ANS):
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Involuntary physiological processes.
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Regulates heart rate, digestion, and more.
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Sympathetic and parasympathetic divisions for balance.
Central Neural System (CNS):
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Brain and spinal cord.
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Central control center.
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Processes sensory information.
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Initiates motor responses.
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Role in cognition, emotion, and consciousness.
Formation of the CNS:
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Originates from a neural tube during embryonic development.
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Complex folding and differentiation.
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Differentiation of neural stem cells into neurons and glial cells.
Protection of the Brain:
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Encased in the bony skull.
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Surrounded by cerebrospinal fluid (CSF) for cushioning.
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Meninges cover the brain and spinal cord.
Forebrain:
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Largest and most complex part of the brain.
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Includes thalamus, hypothalamus, and cerebral cortex.
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Responsible for higher cognitive functions, sensory processing, and physiological regulation.
The Thalamus:
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Acts as a relay station for sensory information.
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Directs signals to the cerebral cortex for processing.
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Important for consciousness and sensory perception.
The Cerebral Cortex:
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Outermost layer of the brain.
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Responsible for reasoning, language, memory, and voluntary muscle movement.
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Highly folded for increased surface area.
