AP Psychology: Biological Bases of Behavior Unit

nature

the influence of our inherited characteristics on our personality, physical growth, intellectual growth, and social interactions

nurture

upbringing and lived experiences

Epigenetics

the study of environmental influences on gene expression that occur without a DNA change

nervous system

the network of nerve cells and fibers that transmits nerve impulses between parts of the body, speedy and electrochemical

Central Nervous System (CNS)

brain and spinal cord, makes decisions for the body

Peripheral Nervous System (PNS)

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

Nerves

bundled axons that form neural "cables" connecting the central nervous system with muscles, glands, and sense organs

sensory (afferent) neurons

neurons that carry incoming information from the sensory receptors to the brain and spinal cord, few million

motor (efferent) neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands, few million

Interneurons

neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs, billions

Somatic Nervous System (SNS)

the division of the peripheral nervous system that controls the body's skeletal muscles

autonomic nervous system (ANS)

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart).

sympathetic nervous system

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations- FIGHT, FLIGHT, or FREEZE

parasympathetic nervous system

the division of the autonomic nervous system that calms the body, conserving its energy- REST & DIGEST

neural networks

interconnected neural cells. With experience, networks can learn, as feedback strengthens or inhibits connections that produce certain results. Computer simulations of neural networks show analogous learning.

endocrine system

the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream

Reflexes

simple, automatic responses to sensory stimuli, such as the knee-jerk response

Neuron

a nerve cell; the basic building block of the nervous system

Neuroplasticity

the ability within the brain to constantly change both the structure and function of many cells in response to experience or trauma

Hypothalamus (endocrine system)

works to maintain homeostasis, controls pituitary gland. part of both the nervous system and the endocrine system.

pituitary gland

The endocrine system's most influential gland, controls all others like a communication center

pineal gland

secretes melatonin

thyroid gland

produces hormones that regulate metabolism, body heat, and bone growth

adrenal glands

a pair of endocrine glands that sit just above the kidneys and secretes adrenaline, arouses the body in times of stress

Pancreas

secretes insulin and glucagon into the bloodstream to help regulate blood glucose levels

Ovaries

produces estrogen and progesterone, once they release these puberty has begun

Testes

produces testosterone, once it releases this puberty has begun

adrenaline

a hormone secreted by the adrenal glands, especially in conditions of stress, increasing rates of blood circulation, breathing, and carbohydrate metabolism and preparing muscles for exertion, fight or flight

Cortisol

stress hormone

Estrogen

A sex hormone, secreted in greater amounts by females than by males. In nonhuman female mammals, estrogen levels peak during ovulation, promoting sexual receptivity.

Progesterone

A hormone produced by the ovaries which acts with estrogen to bring about the menstrual cycle.

Testosterone

the most important of the male sex hormones. Both males and females have it, but the additional testosterone in males stimulates the growth of the male sex organs in the fetus and the development of the male sex characteristics during puberty. involved in sexual arousal and competition (not aggression)

Oxytocin

a hormone released by the pituitary gland, us vs. them, social bonding, maternal & paternal actions stimulate its release, "cuddle hormone"

Melatonin

sleep-inducing hormone

Leptin

(keeps you Lean) hormone that signals the hypothalamus and brain stem to reduce appetite and increase the amount of energy used

Ghrelin

(stomach growling) hormone that increases appetite

Neurotransmitters

Chemicals that transmit information from one neuron to another

excitatory neurotransmitters

excite the next cell into firing

inhibitory neurotransmitters

inhibit the next cell from firing

Acetylcholine (ACh)

A neurotransmitter that enables learning and memory and also triggers muscle contraction and is found in all motor neurons. Undersupply associated with Alzheimer's. Receptors that bind with ACh also bind with nicotine.

Dopamine

A neurotransmitter associated with movement, attention, learning, and the brain's pleasure and reward system, motivation. Addictions are often linked to dopamine releases. Oversupply linked to schizophrenia, undersupply linked to tremors and decreased mobility of Parkinson's.

Serotonin

Neurotransmitter that affects mood, hunger, sleep, memory, bone health, blood clotting, and arousal. Undersupply linked to depression and other mood disorders. Oversupply can result in Serotonin Syndrome. Most serotonin is in the gut.

Gamma-aminobutyric acid (GABA)

Major inhibitory neurotransmitter; alcohol increases GABA levels leading to relaxation, impaired memory, concentration, and motor function, may help regulate anxiety- as in meds such as Valium and Xanax- benzodiazepines. Undersupply is linked to seizures, tremors, anxiety, and insomnia.

Endorphins

"morphine within"--natural, opiate-like neurotransmitters linked to pain control and to pleasure, "runners high," severely injured people's indifference to pain

Epinephrine (adrenaline)

As a neurotransmitter, it's involved in visceral functions like breathing- epipens are medications of epinephrine that can be used to treat anaphylaxis

Norepinephrine (noradrenaline)

Neurotransmitter involved in the fight, flight, or freeze response, helps control alertness & arousal, can increase blood sugar. Meds like Effexor impact its reuptake. Undersupply can depress mood and cause anxiety.

Glutamate

A major excitatory neurotransmitter; involved in memory and learning. Oversupply can overstimulate the brain, causing migraines or seizures (this is why some people avoid MSG)

Agonist

"copycats," agonizing for your work to be stolen. a molecule (produced outside the body) that, by binding to a receptor site, stimulates a response. ex: Morphine, mimics endorphins

Antagonist

"bullies," block you from getting to where you need to be. a molecule (produced outside the body) that, by binding to a receptor site, inhibits or blocks a response. ex: Curare & Botox, both affect Acetylcholine, caffeine blocks adenosine

Agonists , Antagonists

Activate, Against

Dendrite

the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body

Axon

the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands

Myelin Sheath

A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

Nodes of Ranvier

gaps in the myelin sheath

terminal branches of axon

Branched endings of an axon that transmit messages to other neurons

cell body

Largest part of a typical neuron; contains the nucleus and much of the cytoplasm

Synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron

neural connection

the links between brain cells that can be strengthened through activities that regularly stimulate the brain.

Synapse Transmission

The relaying of information across the synapse by means of chemical neurotransmitters.

lesion

tissue destruction. A brain lesion is a naturally or experimentally caused destruction of brain tissue

Electroencephalogram (EEG)

Functional neuroimaging: an amplified recording of the waves of electrical activity that sweep across the brain's surface. These waves are measured by electrodes placed on the scalp and have varying frequencies, amplitudes, & shapes.

computed tomography (CT/CAT) scan

Structural neuroimaging: a series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body. Relatively low resolution, helps identify major structural issues.

positron emission tomography (PET) scan

Functional neuroimaging: patient is injected w/ a radioactive substance that emits positrons that collide w/ tissue & emit gamma rays that are detected by the device. This gives an image of cerebral blood flow, showing the most active areas.

magnetic resonance imaging (MRI)

Structural neuroimaging: uses magnetic fields & radiofrequency energy, hydrogen atoms respond by emitting energy that the machine uses to construct an image, better resolution than a CAT scan.

Functional MRI (fMRI)

Functional neuroimaging: uses magnetic fields & radiofrequency energy, uses different responses of oxygenated and unoxygenated blood to detect changes in blood flow, showing the most active areas & gives a high-resolution structural image

Brainstem (hindbrain)

the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is responsible for automatic survival functions. This is also where many nerves crisscross, so the left hemisphere controls the right side of the body and vice versa, cross-wiring.

medulla oblongata

the base of the brainstem; controls heartbeat and breathing, includes the Pre-Boetzinger complex, which generates breathing rhythm. It also is related to involuntary reflexes like sneezing & vomiting, damage can result in respiratory failure, paralysis, loss of sensation, & termination of heartbeat

Pons

helps coordinate movement, autonomic functions like breathing, taste, sleeping, processing sensory data, & circuts that generate respiratory rhythms. Damage can result in impaired breathing, sleep disturbance, loss of taste and muscle function (excluding eyes,) deafness, locked-in syndrome, paralysis, & death

Thalamus

the brain's sensory switchboard, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

reticular formation

a nerve network in the brainstem that plays an important role in controlling arousal

Cerebellum (little brain)

at the rear of the brainstem; functions include processing sensory input, coordinating movement output and balance, enabling nonverbal learning and memory, judging time, modulating emotions, sequential learning, & discriminating sounds and textures. Damage is associated with loss of fine coordination, imbalance, tremors, vertigo, slurred speech

limbic system

neural system (including the hippocampus, amygdala, and hypothalamus) located below the cerebral hemispheres; associated with emotions and drives. Damage can result in aggression, anxiety, problems with memory, & sexual behavior impairments

Amygdala

two lima bean-sized neural clusters in the limbic system; involved in the creation of emotional memories, emotions like happiness, fear, anger, & anxiety, fear learning, sympathetic nervous system, performs neurogenesis. Damage can result in in/decreases of aggression, irritability, loss of emotional control & recognition, and vulnerability to stress & depression, as well as BPD

Hypothalamus

A neural structure lying below the thalamus; it directs several maintenance activities (eating, drinking, body temperature- all part of homeostasis, all autonomic stuff), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward. Damage can result in mental health conditions such as anxiety, depression, BPD, aggression, & OCD. Hyperactivity: anxiety & agitation, Hypoactivity: depression, lack of motivation, elevated cortisol, PTSD, & mood disorders

older brain functions generally occur

without conscious effort

Reward center of the brain

composed of brain structures that are responsible for mediating the physiological and cognitive processing of reward

Reuptake inhibitors

Drugs that interfere with the reuptake of neurotransmitters in the synapse so that a greater amount remains in the synapse. ex: Selective Serotonin Reuptake Inhibitors (SSRIs) like Prozac & Lexapro

myelinated axons

axons covered with myelin sheaths, much faster than unmyelinated axons

Multiple Sclerosis (MS)

disease of the central nervous system characterized by the demyelination (deterioration of the myelin sheath) of nerve fibers, slowing down or stopping neural communication. Symptoms include movement problems, dizziness, imbalance, fatigue, pain, & heat intolerance.

action potential

a neural impulse; a brief electrical charge that travels down an axon, occurs at the threshold of -55 mV

resting potential

the state of the neuron when not firing a neural impulse, usually around -70 mV. the ratio of negative to positive ions is greater inside the neuron that outside it

all or nothing principle

The principle that once the electrical impulse reaches a certain level of intensity (its threshold @ -55mV), it fires and moves all the way down the axon without losing any intensity.

neurogenesis

the formation of new neurons

basal ganglia

Part of the limbic system that controls voluntary movement, habitual behaviors (implicit memories,) and rewards and reinforcements. Damage can result in tremors, involuntary muscle movements, abnormal posture, movement disorders, & depression symptoms

cerebral cortex

outer region of the cerebrum, containing sheets of nerve cells; gray matter of the brain, associated with our highest mental capabilities

corpus callosum

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them- severed to treat epilepsy

cerebral cortex lobes (Flower POT)

Frontal, parietal, occipital, & temporal

Frontal lobes

the portion of the cerebral cortex lying just behind the forehead; involved in behavioral traits such as personality, decision making, motor control, working memory (short term,) "control panel," executive functioning & higher-order cognition, language production, social behavior, & attention control. Damage can result in personality changes, impaired social judgement, difficulty with motor control, speech production, & impulse control

Parietal lobes

portion of the cerebral cortex lying at the top of the head and toward the rear; processing sensory information & spatial awareness (proprioception,) sensory integration, attention, language processing, math, & the left & right lobes are generally responsible for the other side of the body. Damage can result in hemi-neglect: loss of higher-level awareness of one side of the body, spatial disorientation, & navigational issues

Occipital lobes

portion of the cerebral cortex lying at the back of the head; visual processing: basic visual processing, color recognition, motion perception, reading, visual memory & associations. Damage can result in color blindness, issues with motor perception, & visual agnosia (inability to recognize objects)

Temporal lobes

portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each receiving information primarily from the opposite ear, auditory processing, memory formation & storage, language comprehension, emotion processing, visual perception. Damage can result in difficulties with language comprehension, memory formation (anterograde amnesia,) & emotional regulation

sensory areas of cerebral cortex

receive & process info from various senses- visual cortex (sight,) somatosensory cortex (map of body,) auditory cortex (sound,) & gustatory cortex (taste)

motor areas of cerebral cortex

control voluntary movement, motor homunculus (representational map of body,) premotor cortex (prepares & executes movements,) imitation learning, social cognition & empathy, supplementary motor area (plans complex movement sequences)

association areas of cerebral cortex

integrate info from multiple sensory & motor areas, enable higher-order cognition (abstract thinking, problem solving, language, memory, & attention). Damage can result in agnosia (not knowing)

Broca's area

controls language expression - an area, usually in the left frontal lobe, that directs the muscle movements involved in speech.

Wernicke's area

a brain area involved in language comprehension and expression; usually in the left temporal lobe

Homeostasis

A tendency to maintain a balanced or constant internal state; the regulation of any aspect of body chemistry, such as blood glucose, around a particular level

Resting Membrane Potential

Neuron's stable state at approximately -70 mV.

Refractory Period

Time during which new action potential generation is inhibited.

Signal Transmission

Propagation of action potential along the axon.