Unit 4: Brain and Behavior Flashcards
(117 cards)
EEG
Measurement of electrical activity from surface of scalp to measure activity of cerebral cortex
Synchronous
EEG signal is large, same timing
Asynchronous
EEG signal is small, timing is off
MEG
Detects tiny magnetic signals produced by synchronously active neurons, better at localizing sources of neural activity in brain
4 EEG rhythms
- Beta-awake and alert
- Alpha-awake and resting
- Theta-sleeping
- Delta-deep sleep
Synchronous activity led by one of two things
- Central pacemaker (thalamus)
2. Collective behavior among cortical cells
Zeitgebers
Environmental cues that entrain circadian cycles (primary cue: sunlight)
Internal Circadian Clock
SCN in hypothalamus
Where are higher frequency (beta) waves mainly located?
Cortex
Where are lower frequency (delta) waves mainly located?
Thalamus
Transcriptional-translational feedback loop
- BMAl1 and CLOCK promote transcription of per and cry genes
- Bind together and inhibit transcription of own genes
- Degrade
- Allows BMAL1 and CLOCk to promote per and cry transcription again
EOG
Records eye movements during REM
EMG
Detects muscles activity
4 stages of sleep
- Theta waves
- Spindles and K complexes
- Occasional delta waves
- Predominantly delta waves
Recuperation
Sleep is needed to restore homeostatic balance lost during the day
Adaption
Sleep is the result of an internal timing mechanism, evolved to conserve energy and to protect us from dangers of the night
Effects of sleep deprivation: in support of theory
- Bad mood, reduced cognitive abilities, and sleepiness
- Reduced immune function, increased BP, lower body temp
Effects of sleep deprivation: inconsistent with theory
- Unimpaired logical and critical thinking
- Retained physical strength and motor performance
- Recovery sleep is relatively short
Anterior hypothalamus
Sleep
Posterior hypothalamus
Wake
Rostral reticular formation
Wakeful
Caudal reticular formation
Sleep
Anterior sleep area in hypothalamus (VLPO)
Inhibits targets using GABA as its NT
Posterior awake center (lateral hypothalamic area)
Excited targets using orexin