Parts of the Neuron
Bushy, branching extensions that receive and integrate messages, conducting impulses toward the cell body.
Dendrites
The level of stimulation required to trigger a neural impulse.
Threshold
Connects the body to the CNS by gathering information from the senses and transmitting messages from the CNS.
Peripheral Nervous System
Involved in speaking, motor movements, judgment and decision- making.
Frontal Lobe
Regulates emotions (especially fear and aggression).
Amygdala
The neuron extension that passes messages through its branches to other neurons or to muscles or glands.
Axons
When the neuron fires, transmitting an electrical impulse down its axon by means of a chemistry-to-electricity process.
Action Potential
Part of the PNS that controls the glands and the muscles of the internal organs (such as the heart).
Autonomic Nervous System
The brain’s ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience.
Plasticity
The wide band of axon fibers connecting the two hemispheres of the brain.
Corpus Callosum
Fatty tissue layer segmentally encasing the axons of some neurons; increases transmission speed and provides insulation.
Myelin Sheath
Occurs when the outside of an axon’s membrane has mostly positively charged sodium (Na+) ions and the interior contains negatively charged proteins and a small amount of positively charged potassium (K+) ions.
Polarized or Resting Potential
Part of the PNS that controls the body’s skeletal muscles.
Somatic Nervous System
Makes up most of the brain’s cortex which integrates information involved in learning, remembering, thinking, and other higher-level functions.
Association Areas
At the base of the brainstem, controls heartbeat and breathing
Medulla
The ends of the axon which hold synaptic vesicles that store and release neurotransmitters.
Terminal Branches
The junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron.
Synapse
Part of the autonomic nervous system that arouses the body, mobilizing its energy.
Sympathetic Nervous System
Receives and processes sensory input for touch and body position.
Parietal Lobe
This helps govern the endocrine system via the pituitary gland, linked to emotion and reward.
Hypothalamus
Cells that support, nourish, and protect neurons; they also play a role in learning, thinking, and memory.
Glial Cells
The first section of the semipermeable axon opens its gates once the threshold is met. Then, Na+ ions flood in through the channels.
Depolarization
Part of the autonomic nervous system that calms the body, conserving its energy.
Parasympathetic Nervous System
The intricate fabric of interconnected neural cells covering the cerebral hemispheres. It acts as the body’s ultimate control and information-processing center and is divided into four regions called lobes.
Cerebral Cortex
Filters and relays sensory information except for smell to the appropriate parts of the cerebral cortex
Thalamus