Test Flashcards
The nervous system
A communication network consisting of the nerve cells(neurons) that carry messages both to and from the brain and spinal cord to other parts of the body
Neuroscientists
Study the Brian and the rest of the nervous system in hopes of gaining a better understanding of Normal and abnormal behavior ( consciousness, perception, memory, emotion, stress)
Nervous system functions
- gather and process information
- produce responses to stimuli
- coordinate the workings of the different cells
Central nervous system
- Brian (in the skull)
- spinal cord ( in the spine)
Peripheral nervous system (PNS)
- located outside of the skull and spine
- sensory and motor nerves
CNS
Receives, processes, interprets and stores incoming sensory info
Spinal cord
A collection of neurons and supportive tissue running from the base of the brain down the center of the back
Spinal reflexes
Automatic require no conscious effort ( touching a hot stove )
PSN
Brings sensory information into the CNS and carries motor signals out
Somatic nervous system
Voluntary control of body movements ( nerves connected to sensory receptors and skeletal muscles)
Autonomic nervous system
Involuntary control of visceral functions ( heart rate, digestion, breathing )
- ) sympathetic nervous system
- ) parasympathetic nervous system
Sympathetic nervous system
- Quick response, mobilizing system arousal
- flight or fight
- expend energy
- thoracic and lumbar
Parasympathetic nervous system
- Slowly activated dampening system relaxation
- rest and store
- conserve energy
- cranial and sacral
Neurons
Specialized cells for the receptor, conduction and transmission of electrochemical signals
Glia
Cells that provide support,nurture, and insulate neurons, remove debris when neurons die, enhance the formation and maintenance of neural connections, and modify neuronal functioning
Sensory neurons
Carry incoming information from the sense receptors to the CNS
Motor neurons
Carry outgoing information from the CNS to muscles, glands and organs
Interneurons
Connect the 2 neurons
Cell body
Life support center
Dendrites
Receives messages from other cells
Axon
Passes messages away from the cell body to other neurons, muscles, or glands
Neural impulse
Electrical signal traveling down the axon
Myelin sheath
Covers the axon of some neurons and helps speed neural impulses
Neurogenesis
Production of new neurons from immature stem cells
Stem cells
Immature cells that renew themselves and have the potential to develop into mature cells
Neural plasticity
The Brian’s ability to change and adapt in response to experience, through neurogenesis, or by reorganizing or growing new neural connections
- Brian can recover from damage
Threshold
When the excitatory signals minus the inhibitory signals exceed a minimum intensity(threshold) the neuron fires an action potential
Action potential
Brief change in electrical voltage that occurs between the inside and outside of an axon when a neuron is stimulated
-creates an electrical impulse
All or non response
Intensity of an action potential remains same along length of the axon
Neurotransmitter
Chemical substance released by a transmitting neuron at the synapse and that alters the activity of a receiving neuron
- neurotransmitter released by vesicles in the axon terminal
- neurotransmitter enters synapse
Neurons communicate by:
- Neurotransmitter binds to specific receptors on the post synaptic cell that it fits ( lock and key)
- depending on the type of neurotransmitter, once it binds to the receptor it can have either and excitatory effect or an inhibitory effect on the postsynaptic cell
Acetylcholine
Neurotransmitter used by the spinal cord neurons to control muscles and by many neurons in the Brian to regulate memory
Dopamine
Produces feelings of pleasure when released by the brain reward system
Gamma-aminobutyric (GABA)
Inhibitory neurotransmitter in the brain
Glutamate
Excitatory neurotransmitter in the Brian
Norepinephrine
Hormones, fight or flight response
Serotonin
Mood, appetite, and sensory perception, pain pathways ,sleepy
Endocrine system
Release hormones into the bloodstream
- secreted by glands that affect the functioning of other organs( regulating growth, metabolism, sexual development)
- long distance messengers
Melatonin
Regulates daily biological rhythms
Oxytocin
Secreted by the pituitary gland; enhances uterine contractions during childbirth, facilitates ejection of milk during nursing
Adrenal hormones
Involved in emotions and stress ( cortisol, epinephrine and norepinephrine
Sex hormones
Regulate development and functioning of reproductive organs ( androgens, estrogens and progesterone)
Pons
Involved in sleeping, waking and dreaming
Medulla
Responsible automatic functions ( breathing and heart rate )
Reticular activating system
- dense network of neurons
- arouses the cortex and screens incoming information
The cerebellum
- regulates movement and balance
- involved in remembering simple skills and acquired reflexes
- problem solving and understanding words
Thalamus
-relays sensory messages to the cerebral cortex-includes all sensory messages except those from olfactory bulb
Limbic system
A group of brain areas involved in emotional reaction and motivated behavior
- hypothalamus
- hippocampus
- amygdala
Hypothalamus
- involved in emotions and drives vital to survival (hunger, thirst)
- regulates autonomic nervous system
- helps govern endocrine system (pituitary gland)
Amygdala
- responsible for arousal
- regulation of emotion, initial emotional response to sensory information
- plays important role in mediating anxiety , depression, and emotional memory
Hippopotamus
- storage of new information in memory
- comparing sensory Information with what the brain expects about the world
- enabling us to form spatial memories for navigating the environment