Behavioral Neuroscience Chapter 8.2

Sleep

1) sleep is a state that the brain actively p…….
- characterized by a moderate d……. In brain a……. and d…….. Response to s……

2) sleep differs from the following states:
- coma, vegetative state, minimally conscious state, and brain death.

Stages of sleep and brain mechanisms

sleep is a specialized state evolved to serve particular f……..

Other interruptions of consciousness

1) coma: extended period of un…………. Characterized by low b…. A……. That remains fairly steady
- person shows little response to s……

2) vegetative state: person alternates between periods of s…. And moderate A…… But no awareness of s……….
- some autonomic arousal to p…… Stimulus
- no purposeful activity/ response to speech

Other interruptions of consciousness

1) minimally conscious state:
one stage higher than a v……… state marked by occasional brief periods of purposeful a….. and limited s….. comprehension.

2) brain death:
No sign of b…. a……. and no response to any s…….

Stages of sleep- EEG

1) the electroencephalograph (EEG) allowed researchers to discover that there are various stages of s….
- allows researchers to compare b…. A……. At different times during s….

2) a polysomnograph is a combination of EEG and eye-m……. Records
- polysomnograph– earliest form used to study a brain combo of eye and brain activity

Stage 1 sleep

1) alpha waves are present when one begins a state of R………

2) stage 1 sleep is when sleep has just b….
- the EEG is dominated by irr……, jag…, and low volt… Waves
- brain activity begins to d……

— progress into this as you “drift off” into sleep

Stage 3&4 sleep

1) stage 3 & 4 together constitute s… W… S…. (SWS) and is characterized by:
2) EEG recording of s…, Large amplitude w…
3) slowing of h…. R…, b…….. R…, and b…. A…….
4) highly synchronized n……. a…….

Paradoxical or REM Sleep

1) R…. E.. M……. Sleep (REM) describes periods characterized by R…. E.. M……. During sleep
2) also known as para…… Sleep: deep sleep in some ways, but light sleep in other ways
3) EEG waves are irr……, L..-v……, and f…
4) postural m…… of the body are more relaxed Than other stages

NREM & REM Cycles

1) stages other than REM are referred to as non-R.. Sleep (NREM)
2) when people fall asleep, they progress through stages 1, 2, 3, & 4 in seq……. Order
3) after about an hour, the person begins to cycle back through the stages from stage ? To stages ? And ? And then REM
4) the sequence repeats with each cycle lasting approximately ?? Minutes

NREM & REM Cycles

1) stage ?&? sleep predominate early In the night
- length of stage d…….. As the night progresses
2) … Sleep is predominant later at night
- length i…….. As the night progresses
3) REM is strongly associated with d……., but people also report d……. In other stages of sleep

Brain Mechanisms of Wakefulness and Arousal- Reticular Formation

1) various brain mechanisms are associated with w………. And a……
2) the R…….. F…….. Is a part of the midbrain that extends from the medulla to the forebrain and is responsible for arousal

Brain mechanisms of wakefulness and arousal- pontomesencephalon

1) the pontomesencephalon, a part of the mid….., contributes to cortical arousal

2) axons extend to the hypo…….., thal…., and b…. forebrain, which release acetylcholine and glutamate
Glutamate=primary excitatory

3) produce e……… effects to widespread areas of the cortex
4) stimulation of the pontomesencephalon awakens sleeping individuals and i…….. Alertness in those already a….

Brain mechanisms of wakefulness and arousal - locus coeruleus

1) the locus coeruleus is a small structure in the pons whose axons release norepinephrine to a….. various areas of the cor… and i……. W……….
- usually dormant while a…..

Brain mechanisms of wakefulness and arousal - hypothalamus

1) the hypothalamus contains neurons that release “histamine” to produce widespread ex…….. Effects throughout the brain
- antihistamines produce s………

Brain mechanisms of wakefulness and arousal - orexin

1) orexin releases acetylcholine-releasing cells in the basal forebrain to stimulate neurons responsible for w………. And a……
- the basal forebrain is an area just anterior and dorsal to the hypo……..

Brain mechanisms of wakefulness and arousal - GABA and Acetycholine

1) cells of the basal forebrain release the inh……. Neurotransmitter GABA
- inh……. Provided by GABA is essential for sleep

2) other axons from the basal forebrain release Acetycholine, which is ex…….. And inc…… Arousal

Sleep and the inhibition of brain activity

1) functions of the inhibitory neurotransmitter GABA are also important for:
- decreasing the t………. And m…….. Rate
- decreasing the s……… of neurons

Sleep as a local phenomenon

1) sleep can be localized within the b….
- sleep…….: awake in one part of the brain and asleep in others
- the pons remaining in REM while other brain areas wake up: causes the in……. To move

Brain function in REM Sleep

1) during REM sleep:
- activity increases in the po.. and the lim… System

-activity decreases in the primary vi…. cortex, the mo… cortex, and the dorsolat…. prefr….. cortex
(Cortical area decreases)

Brain function in REM Sleep

1) REM sleep is also associated with a distinctive pattern of high-amplitude electrical potentials known as P?? waves
- waves of neural activity are detected first in the pons, then in the lateral geniculate of the hypothalamus, and then the occipital cortex
2) REM dep…….. results in a high density of PGO waves during un……….. sleep

Brain function in REM sleep

1) cells in the pons send messages to the spi… C… Which in…… Motor neurons that control the body’s large muscles
- prevents motor movement during REM sleep
2) REM is also regulated by sero….. And Acetycholine
- drugs that stimulate Acetycholine receptors quickly move people to REM
- serotonin interrupts REM

Sleep disorders

1) a sleep disorder with inadequate sleep
- caused by a number of factors, including noi.., str…, pa.., di.., and medication
- can also be the result of disorders such as epil…., park…..’s disease, depr……, anx…. Or other conditions
- dependence on sleeping pills or alcohol and shifts in the circadian rhythms can also result in inso….

Sleep apnea

1) a sleep disorder characterized by the inability to b…… While sleeping for a prolonged period of time
2) consequences: s……… during the day, impaired att……, depr……, and sometimes hea.. problems
3) causes: gene…., hor….., old age, obe…. And deterioration of the br… Mechanisms that control bre……
4) effects: cognitive impairment may result