Brain Plasticity and Nervous System Components

Brain Plasticity and Function

• Brain plasticity is the brain's ability to change, particularly during childhood, by reorganizing after injury or forming new pathways based on experiences.

Nervous System Components

• Neuron: The basic unit of the nervous system, a nerve cell.
• Cell Body: The neuron's life-support center, containing the nucleus.
• Dendrites: Neuron extensions that receive and transmit messages toward the cell body.
• Axon: The neuron extension that sends messages to other neurons, muscles, or glands.
• Action Potentials: Brief electrical impulses that travel down the axon.
• Glial Cells: Support, nourish, and protect neurons; play a role in learning, memory, and thinking.
• Synapses: Junctions between neurons where messages pass.
• Synaptic Gap/Cleft: The tiny space between neurons at a synapse.
• Neurotransmitters: Chemicals released by neurons to transmit messages across synapses.
• All-or-None Law: Neurons fire completely or not at all.
• Threshold: The stimulation level required to trigger a neural impulse.
• Refractory Period: Brief pause after a neuron fires, preventing immediate subsequent firing.

Nervous System Structures and Functions

• Nervous System: The body's electrochemical communication network.
• Peripheral Nervous System: Sensory and motor neurons connecting the central nervous system to the rest of the body.
• Central Nervous System: The brain and spinal cord.
• Endocrine System: The body's "slow" chemical communication system, using hormones.
• Hormones: Chemical messengers that travel through the bloodstream, affecting tissues.
• Limbic System: Neural system associated with emotions and drives (amygdala, hypothalamus, and hippocampus).
• Frontal Lobes: Involved in speaking, muscle movements, planning, and judgments.
• Parietal Lobes: Receive sensory input for touch and body position.
• Occipital Lobes: Receive information from visual fields.
• Temporal Lobes: Receive information from the ears.
• Motor Cortex: Controls voluntary movements.
• Somatosensory Cortex: Registers and processes sensations like touch and body movement.
• Association Areas: Involved in higher mental functions like learning, remembering, thinking, and speaking.
• Corpus Callosum: Connects the two brain hemispheres, allowing communication between them.
• Neurogenesis: Formation of new neurons.

States of Awareness

• Consciousness: Subjective awareness of oneself and the environment.
• Selective Attention: Focusing awareness on a specific stimulus.
• Inattentional and Change Blindness: Failing to notice changes in the environment, a form of inattentional blindness.

This section discusses brain plasticity, which is the brain's ability to change, especially in childhood. It also introduces fundamental components of the nervous system such as neurons, cell bodies, dendrites, axons, glial cells, synapses, and neurotransmitters.