chapter 9 Flashcards
electromyogram (EMG)
an electrical potential recorded from an electrode placed on or in a muscle
electro-oculogram (EOG)
an electrical potential from the eyes, recorded by means of electrodes placed on the skin around the; detects eye movements
alpha activity
smooth electrical activity of 8-12 Hz recorded from the brain; generally associated with a state of relaxation
beta activity
irregular electrical activity of 13-30 Hz recorded from the brain; generally associated with a state of arousal
theta activity
EEG activity of 3.5-7.5 Hz that occurs intermittently during early stages of slow-wave sleep and REM sleep
slow wave sleep
non- REM sleep characterized by synchronized EEG activity during its deeper stages
delta activity
regular, synchronous electrical activity of less than 4 Hz recorded from the brain; occurs during the deepest stages of slow-wave sleep
REM sleep
a period of desynchronized EEG activity during sleep, at which time dreaming, rapid eye movements, and muscular paralysis occur; also called paradoxical sleep
rebound phenomenon
the increased frequency or intensity of a phenomenon after it has been temporarily suppressed; for example, the increase in REM sleep seen after a period of REM sleep deprivation
adenosine
a neuromodulator that is released by neurons engaging in high levels of metabolic activity; may play a primary role in the initiation of sleep
locus coeruleus
a dark colored group of noradrenergic cell bodies located in the pons near the rostral end of the floor of the fourth ventricle; involved in arousal and vigilance
raphe nuclei
a group of nuclei located in the reticular formation of the medulla, pons, and midbrain, situated alone the midline; contain serotonergic neurons
tuberomammillary nucleus (TMN)
a nucleus in the ventral posterior hypothalamus just rostral to the mammillary bodies; contains histaminergic neurons involved in cortical activation and behavioral arousal
orexin
a peptide, also known as hypocretin, produced by neurons whose cell bodies are located in the hypothalamus; their destruction causes narcolepsy
ventrolateral preoptic area
a group of GABAergic neurons in the preoptic area whose activity suppresses alertness and behavioral arousal and promotes sleep
sublaterodorsal nucleus
a region of the dorsal pons just ventral to the locus coeruleus that forms the REM-ON portion of the REM sleep flip flop
ventrolateral periaqeductal gray matter
a region of the dorsal midbrain that forms the REM-OFF proportion of the REM sleep flip flop
sleep apnea
cessation of breathing while sleeping
narcolepsy
a sleep disorder characterized by periods of irresistible sleep, attacks of cataplexy, sleep paralysis, and hypnagogic hallucinations
sleep attack
a symptom of narcolepsy; an irresistible urge to sleep during the say, after which the person awakens feeling refreshed
cataplexy
a symptom of narcolepsy; complete paralysis that occurs during waking
sleep paralysis
a symptom of narcolepsy; paralysis occurring just before a person falls to sleep
hypnagogic hallucination
a symptom of narcolepsy; vivid dreams that occur just before a person falls asleep; accompanied by sleep paralysis
REM sleep behavior disorder
a neurological disorder in which the person does not become paralyzed during REM sleep and thus acts out dreams
sleep-related eating disorder
a disorder in which the person leaves his or her bed and seeks out and eats food while sleepwalking, usually without a memory for the episode the next day
circadian rhythm
a daily rhythmical change in behavior or physiological process
zeitgeber
a stimulus that resets the biological clock that is responsible for circadian rhythms
suprachiasmatic nucleus
a nucleus situated atop the optic chiasm. It contains a biological clock that is responsible for organizing many of the body’s circadian rhythms
melanopsin
a photo pigment present in ganglion cells in the retina whose axons transmit information to the SCN, the thalamus, and the olivary pretectal nuclei
advanced sleep phase syndrome
a four hour advance in rhythms of sleep and temperature cycles, apparently caused by a mutation of a gene involved in the rhythmicity of neurons of the SCN
delayed sleep phase syndrome
a four hour delay in rhythms of sleep and temperature cycles possibly caused by a mutation of a gene involved in the rhythmicity of neurons in the SCN
pineal gland
a gland attached to the dorsal tectum; produces melatonin and plays a role in circadian and seasonal rhythms
melatonin
a hormone secreted during the night by the pineal body; plays a role in circadian and seasonal rhythms
