PHYSIOLOGY/NEUROSCIENE Flashcards
PHYSIOLOICAL PSYCHOLOGY
- study of essential biology invovled in the study of mind
Central nervous system (CNS) 2 parts:
1) brain
2) spinal cord
Afferent fibers
- run toward CNS
Efferent fibers
- run away from CNS
Peripheral Nervous System (PNS) (2 parts)
- runs to and from the CNS
1) somatic nervous system
2) autonomic nervous system
Somatic nervous system
- interacts with external environment by controlling voluntary of muscles
Autonomic nervous system
- interacts with internal environment and responsible for flight and fight
- controls involuntary function e.g. digestion, blood circulation
ANS and (2 parts)
- internal environment and involuntary controls that are responsible for flight or fight
1) sympathetic nervous system
2) parasympathetic nervous system
Sympathetic nervous system
- arousal mechnicism e.g. circulation, threat and fear response
Parasympathetic nervous system
- responsible for recuperation after arousal e.g. lowering heart rate, blood pressure
Spinal Cord
- go to and from the brain
- inner core of gray matter (cell bodies and dendrites) and outer covering of white matter (nerve fibers, axon bundles, and myelin sheathing)
Brain
- extension of the spine
- brain has developed from the base to the front
Hind brain parts:
- myelencephalon (aka medulla)
- metencephalon (pons) and cerebellum
- reticular formation (oldest part of the brain)
Myelencephalon (medulla) (hindbrain)
- reflexes, sleep, attention, movement
Metecephalon (hindbrain)
- pons (connets brain to spine)
- cerebellum - mscle coordination, balance posture
Reticular formation (hindbrain)
- some in hindbrain and midbrain
- oldest part of brain, alertness, thirts, sleep, involuntary muscles at heart
Mesencehalon AKA midbrain
- tectum
- tegmentum
Tectum (midbrain)
- controls vision and hearing
Tegmetum (midbrain)
- rest of reticular formation
- sensorimotor system and analegesic effect opiates
Forebrain - divided into what 2 parts:
- divided into dicephalon (thalamus and hypothalamus) and telencephalon (essentially rest of forebrain)
Corticospinal tract (forebrain)
- connections between brain and spine
Thamalmus (diencephalon)
-channels sensory info into cerebral cortex
Hypothalamus (diencephalon)
- controls ANS biological motivations e.g. hunger, thirst, pituary gland
Pituitary gland
- master gland of the endocrine/hormone system
Limbic system (telencephalon)
- in brainstem invovling the 4 F’s (fleeing, feeding, fighting, fornicatin)
Hippocampus (telencephalon)
- memory, transferring short-term memory into LTM
- new neurons can form in the hippocampus
Amygdala (telencephalon)
- control emotional reactions e.g. fear and anger
Cingulate gyrus (telencephalon)
- links areas in the brain dealing with emotion and decisions
Cerebral cortex
- outer half-inch of cerebral hemisphere
- senosry and IQ functions split into 2 lobes
- 90% neocortex
- 10% less than 6 layers and more primitive
Frontal lobe
- control speech, reasoning, problem solving
- houses Broca’s area of speech
Occipital lobe
- vision
Parietal lobe
- somatosensory system
Temporal lobe
- hearing
- houses Wenike’s area related to speech
Gyri
- bumps
Sulci
- fissures
Meninges
- tough connective tissues that cover and protect the brain and spinal cord
Blood brain barrier
- protects brain by making it difficult for toxic substances to pass from blood into brain
- cells that make up blood vessels in brain are very tightly packed
Ventricles
- chambers filled with cerebrospinal fluid that insulate brain from shock
Superior colliculus
- controls visual reflexes
Inferior colliculus
- controls auditory reflexes
Basal ganglia
- large voluntary muscle movements
- dengeneration related to motor dysfuction
Cortical association areas
- cortex that correspond to certain functions
- larger the area the more sensitive and highly accessed is the corresponding function
Apraxia
- inability to organize movement
Agnosia
- difficulty processing sensory information
Aphasia
- language disorder
Alexia
- inability to read
Agraphia
- inability to write
Broca’s aphasia
- damage to Broca’s area in left frontal lobe
- understand speech but difficulty speakng
Wernicke’s aphasia
- damage to Wernicke’s area of brain located in the left temporal lobe
- can speak but no longer understand how to correctly choose words
- speech is fluent but nonsensical
Hyperphagia
- overeating with no satiation of hunger
- damange to the ventromedial region of the hypothalamus
Sham rage
- incredibly rage easily provoked when the cerebral cortex is removed
Stereotaxic instruments
- used to implant electrodes
Functional magnetic resonance imaging (fMRI)
- measures oxygen flow in brain
Positron emission tomography (PET)
- scans glucose metabolism
Blooming and pruning
- process children go through where neural pathways are connected and then some die out
Neuron
- basic unit of the nervous system
Dendrites
- receive impulses
Cell body AKA
- soma
- largest central portion and makes up gray matter
- has a nucleas that directs the neuron’s activity
Axon hillock
- where the soma and axon connect
Axon
- transmits impulses of the neuron
- bundle of these nerve fibers aka white matter
- wider the the nerve fiber the faster the conduction of axon impulses
Myelin sheath
- fatty insulated sheath on axons that allow faster conduction of axon impulses
Nodes of Ranvier
- dips between the beads of myelin sheath
Terminal buttons
- jumping points for impulses
Synaptic vessels
- found inside terminal butttons and hold transmitters
Cell membrane
- covers the whole neuron and has selective permeability
- sometimes lets positive ions through
Synpase or synpatic gap
- space between 2 neurons where they communicate
Presynaptic cell
- end of one neuron (terminal buttons)
Postsynaptic cell
- beginning of another neuron (dendrites)
Glial cells (2 types)
- other types of cells in nervous system
1) oligodendrocytes
2) schwann cells
Oligodendrocytes
- provide myelin in CNS
Schwann cells
- provide myelin in the PNS
Resting potential
- inactivated state of neuron
- negatively charged and positive ions cannot get in
Presynaptic cell fires and:
- releases NT from its terminal button as a messenger
Postsynaptic potentials and postsynaptic cell detect presence of NT and:
- cause ion channels to open up
Postsynaptic potential (2 forms):
- changes in nerve cell’s charge as the result of stimulation
1) EPSP
2) IPSP
Excitatory postsynaptic potential (EPSP)
- positive charges from outside are allowed in (depolarization) and increase chance that cell will fire
Depolarization
- increases the chance that cell will fire
Inhibitory postsynaptic potential (IPSP)
- few positive charges in cell body are let out (hyperpolarizaton) and body is even more negative than outside
- decrease chance that cell will fire
Action potential or nerve impulses
- when cell stimulated with enough positive ions and fires
The all or none law
- refers to fact that once minimum threshold for stimulation is met = nerve impulses sent
- intensity always the same
- indicates how many signals are fired not how strong the stimulus is
How does the action potential travel down the axon:
- frequently ‘jumping’ from one node of Ranvier to the next bc on increased insulation
Saltatory conduction
- jumping from one node to next
Absolute refractory period
- time after a neuron fires in which it cannot respond to stimulation
Relative refractory period
- time after absolute refractory where neuron can fire but it needs a stronger stimulus
What happens after NT is done? (2 things)
1) reuptake where NT is reabsorbed into synpatic cell
2) deactivated by enzymes
- process keeps messenger from continually stimulating neurons
Acteylcholine
- released at neuromuscular junction to cause contraction of skeletal muscles
- invovled in parasympathetic nervous system
Endorphines
- pleasure and analgesia
- exogenous endorphines are highly addictive
Monoanimes (2 classes)
- comprise of 2 classes of NT
1) Indolamnes
2) Catecholamines
Indolamines
- include serotonin
Catecholamines
- include dopamine - related to reward and addiction
- too little = motor degenerative disease
- too much = schizophrenia
Amno acids
- present in fast acting directed synapses
Glutamate
- most abundent excitatory NT
Gamma-aminobutyric acid (GABA)
- most abundent inhibitory NT
Neuromodulators
- NT that cause long term changes in postsynaptic cell
Agonists
- NT increases effect of Nt e.g. SSRIS increase serotonin activity
Antagonists
- decrease the effect of specific NT
e. g. botox an acetylcholine that decrease muscle activity
Pituitary gland
- controlled by hypothalamus and regulates hormones in body
- characterized as either organizational or activational
H-Y antigen (organizational)
- presence during development causes fetus to be a male
Androgens (testosterone; organizational)
- increase in males causes genital maturity and secondary sex characterisitcs
Estrogen (organizational)
- increase females genital maturity and secondary sex characteristics
Mearche (organizational)
- onset of menstrual cycle
Lutenizing hormone (LH) and follicle stimulting hormone (FSH) (activational)
- hormones that changes during menstrual cycle
- regulate development of ovum and trigger ovulation in females
- promotes sperm development and testosterone
- also estradiol, progesterone
Oxytocin
- released in pituitary and facilitate birth and breast feeding
- involved in pair bonding
Vasopressin
- released in pituitary
- reglates water levels in body and blood pressure
Thyriod stimulating hormone
- released from the pituitary
- activates the thyroid
Adrenocorticotropic hormone (ACTH)
- released from the pituitary
- stress hormone that increases production of androgens and cortisol
Electroencephalograms (EEG)
- measure brain wave patterns and sleep/wake states
Sleep has 2 phases:
1) Non REM: takes about 1/2 hour to pass through 4 stages
2) REM
Stage 0 (non rem)
- prelude to sleep
- low amplitude and fast frequency alpha waves appear in brain
- relaxed and drowsy
Alpha waves in stage 0 (low amplitude, fast frequency) AKA
- neural synchrony
Stage 1 (non rem)
- eyes roll
- alpha waves turn into irregular theta waves (low amplitude and slow frequency)
- loses responsiveness and has fleeting thoughts
Stage 2 (non rem)
- AKA theta wave stage
- fast burst of brain activity called sleep spindles
- muscle tensions, heart decline, respiration and temperature decline
Sleep Spindles
- fast frequency bursts of brain activity
Stage 3 (non rem)
- takes 30 mins after falling asleep
- few sleep spindles
- high amplitude and low frequency delta waves
Stage 4 (non rem)
- delta waves occur more than 50% of time
- deepest level of sleep during delta waves
- heart rate, temperature, blood flow rduced and GH is secreted
- if woken up, person is groggy and confused
REM
- 20% is REM; interspersed with non REM every 30-40 mins
- dreams are experienced
- same low amplitude, fast frequency beta waves of waking state (neural desynchrony) but mscles decrease to paralysis and sudeen twiches
- last from 15 mins to 1 hour
Beta waves in REM sleep (low amplitude, high frequency) AKA
- neural desynchrony
REM AKA
- paradoxial sleep
Rebound effect
- when people are deprived of REM sleep
- compensat the next night by spending more time in REM sleep
How many cycles of sleep to people complete? How long is each cycle? What stages take place when?
- 4 - 6 each night
- each cycle last 90 mins
- stage 3 and 4 early in night then stage 2 and REM later on in night
Infant vs. Eldery sleep hours
- 16 vs. 6
REM sleep comprises of how much sleep in birth and the decreases to:
- comprises of half of total sleep then decreases to 25%
