chapter 2 Flashcards
what is a neuron?
- the basic unit of the nervous system
- a nerve cell
- receives signals from neurons or sensory organs
- processes information
- sends signals to other neurons, muscles, organs
what are glial cells and what do they do?
- fill the gaps between neurons (glia = glue)
- nutrition and maintenance of nerve cells
- some involved in brain’s immune response
what are dendrites and what do they do?
part of neuron; receive signals from other cells
what is the cell membrane and what does it do?
part of neuron; protects the cell
what is an axon and what does it do?
part of neuron; transfers signals to other cells and organs
what is the myelin sheath and what does it do?
part of neuron; increases the speed of a signal
a layer of fatty tissue that insulates them and speeds their impulses
what are the neurotransmitters?
chemical messengers
- Acetylcholine (ACh)
- Dopamine(DA)
- Norepinephrine (NE)
- Serotonin (5-HT)
- GABA
- Glutamate (Glu)
- Endorphins
what does acetylcholine do?
learning + memory, muscle movement
problems: Alzheimer’s disease
what does dopamine do?
movement, learning, attention, emotion
problems: Schizophrenia (too much), Parkinson’s (too little)
what does norepinephrine do?
alertness and arousal
problems: depression, bipolar disorder
what does serotonin do?
mood, hunger, sleep, arousal
problems: depression, bipolar disorder
what does GABA do?
inhibitory action (calms firing of cells)
problems: generalized anxiety disorder, insomnia, seizures, tremors
what does glutamate do?
excitatory action (increases firing of cells), memory
problems: schizophrenia, migraines, seizures
what do endorphins do?
pain and pleasure
problems: too much can alter body’s production of natural endorphins
what are the 2 main parts of the nervous system?
- central nervous system
- peripheral nervous system
what does the central nervous system consist of?
the brain and the spinal cord
what does the peripheral nervous system consist of?
- motor neurons (somatic and autonomic (sympathetic and parasympathetic))
- sensory neurons
what does an EEG do?
an electroencephalogram reads the electrical activity of cells
- brain computer interface
what are methods of observing the brain?
- EEG
- MEG
- MRI
- PET
- fMRI
what does an MEG do?
a magnetoencephalography maps activity by recording magnetic fields from electricity in the brain
what is an MRI?
a magnetic resonance imaging visualizes brain structure
what is a PET scan?
a positron emission tomography visualizes brain function by tracking radioactively tagged glucose used as energy in brain functions
what are the parts of the brain stem?
- medulla
- pons
- reticular formation
(near the brainstem) - thalamus
- cerebellum
what does the medulla control?
heartbeat & breathing
what does the pons control?
sleep control & movement coordination
what does the reticular formation control?
arousal/alertness levels (if severed leads to permanent coma)
what does the thalamus do?
receives sensory info, relays info to higher brain regions
what does the cerebellum control?
coordination of movement and balance, involved in nonverbal learning and memory
what is the limbic system and its major components?
associated with memory and drives
- hippocampus
- amygdala
- hypothalamus
what is the hippocampus?
memory formation of facts,
events, & spatial awareness
what is the amygdala?
linked to emotions, especially
aggression & fear
what does the hypothalamus do?
- maintenance & motivational
behaviors - homeostasis
- thirst & hunger
- linked to reward & pleasure via nucleus accumbens (in humans more likely to produce desire)
what is the cerebral cortex?
the largest division of the brain. divided in 2 hemispheres, each divided into 4 lobes
what are the different lobes of the brain?
occipital lobe, temporal lobe, parietal lobe, frontal lobe
where is the occipital lobe and what’s its functon?
at the back of the head, many aspects of vision
where is the temporal lobe and what’s its function?
around the ears, hearing
where is the parietal lobe and what’s its function?
top, rear of the brain; attention, spatial location, somatosensory control
where is the frontal lobe and what’s its function?
front of the brain; planning, memory search, motor control, reasoning
what is the somatosensory strip?
front of the parietal lobe; a strip of brain tissue that processes sensory information from the body, such as touch, pressure, temperature, and pain
what is the motor strip?
rear of frontal lobe; a narrow strip of brain tissue in the frontal lobe that controls movement
what are some association areas?
Broca’s- speech production and articulation
Wernicke’s- understanding written and spoken language
what does the left hemisphere of the brain control?
right side of body
language/ speech
reading
writing
logic
math
science
interpretation of events
what does the right hemisphere of the brain control?
left side of the body
spatial relations
creativity
inference
fantasy
music & art
helps orchestrate self-awareness
what is brain lateralization?
the process by which different parts of the brain control specific cognitive skills and behaviors
what is the corpus callosum responsible for?
connecting the left and right hemispheres of the brain, allowing them to communicate
what are behavioral genetics?
a field of research that studies genetics and how it contributes to, influences, and is influenced by individual differences in behavior
- nature vs nurture
what are chromosomes?
threadlike structures made of DNA molecules that contain the genes
what is DNA?
molecules that contains genes
what is a gene?
a stretch of DNA that produces specific protein
what is inheritance?
the joint action of combinations of genes working together
what are research practices for behavioral genetics?
adoption studies and twin studies
what are examples of gene-environment interaction?
- Environment acts on gene expression
- Gene expression leading to certain characteristics affects environment
- Choices we make are influenced by and affect both our gene expression & our environment
what is a neural impulse
Neurons transmit messages when stimulated by our senses or by neighboring neurons. A neuron sends a message by firing an impulse,
what is an action potential
a neural impulse; a brief electrical charge that travels down an axon
what is a refractory period
in neural processing, a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state
what is the threshold
the level of stimulation required to trigger a neural impulse
what is the all or none response
a neuron’s reaction of either firing (with a full-strength response) or not firing
what is a synapse
the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron
what is the synaptic gap
The tiny gap at this junction
what is reuptake
a neurotransmitter’s reabsorption by the sending neuron
what is the axon terminal
the end of the axon, synaptic gap
what is the nervous system
a communication network that takes in information from the world and the body’s tissues, makes decisions, and sends back information and orders to the body’s tissues
what are the 3 types of neurons
Sensory neurons carry messages from the body’s tissues and sensory receptors inward (what biologists term afferent) to the brain and spinal cord for processing. Motor neurons (which are efferent) carry instructions from the central nervous system outward to the body’s muscles and glands. Between the sensory input and motor output, information is processed via interneurons.
what does the somatic nervous system do
enables voluntary control of our skeletal muscles
what does the autonomic nervous system do
controls our glands and our internal organ muscles
what is the difference between sympathetic and parasympathetic nervous systems
The sympathetic nervous system arouses and expends energy. your parasympathetic nervous system will produce the opposite effects, conserving energy as it calms you. work together to keep us in a steady internal state called homeostasis
what is a reflex
a simple, automatic response to a sensory stimulus, such as the knee-jerk reflex.
what is the endocrine system
the body’s “slow” chemical communication system; a set of glands and fat tissue that secrete hormones into the bloodstream
what are hormones
chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues
what is the adrenal gland
a pair of endocrine glands that sits just above the kidneys and secretes hormones (epinephrine and norepinephrine) that help arouse the body in times of stress
what is the pituitary gland
the endocrine system’s most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands
what does lesion mean
tissue destruction. Brain lesions occur naturally (disease or trauma), in surgery, or experimentally (using electrodes to destroy brain cells)
what are split brains
a condition resulting from surgery that separates the brain’s two hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them.
what are differences between the right and left brain hemispheres
The right hemisphere typically activates during perceptual tasks, while the left is engaged during speech and mathematical calculations. The left hemisphere excels at quick, literal interpretations, whereas the right hemisphere is better at making inferences and understanding subtleties in language.
what is our environment
every nongenetic influence, from prenatal nutrition to our experiences of the people and things around us.
