Variations in Consciousness Continued

Welcome to 2010!!!

Drill Experts say, “Early to rise isn’t making kids wise – it’s making them sleepy.” Should early-start schools move to a later start time or is this impractical? Explain your responses.

Have you continued your sleep diary through break? If not, be sure to add tonight to your diary. You should have at least 3 – 5 nights. The more the better!

Important Dates January 4, 5 & 6 ~ Finish Chapter 5 January 7 ~ Chapter 5 Vocabulary Due January 8 ~ Take Home Test Chap. 5 January 11 ~ Test Due & Begin Chap. 4 »Chap. 4 Vocabulary #1 ~ Due Jan. 12 »Chap. 4 Vocabulary #2 ~ Due Jan. 19 »Chap. 4 Vocabulary #3 ~ Due Jan. 26 January 28 ~ Chapter 4 Test January 29 ~ Begin Chapter 6

Sleep Odds & Ends Age ~ alters sleep cycle –Newborns Sleep 6 to 8 times, exceeding 16 hours of total sleep –Infants Spend much more time in REM sleep than adults (50% for infants, 20% for adults), but continues to decline as one ages –Adults Shifts are seen toward lighter sleep & cause increased waking during the night

Sleep Odds & Ends Culture –Co-Sleeping –The practice of children and parents sleeping together »In western culture, this is discouraged »In Japanese cultures, it is emphasized as interdependence and group harmony »Co-sleeping is more normative than not ~ and pressure against it appears to be an urban & western phenomonon –Napping –In many societies, shops close and activities are halted in the afternoon for a 1 – 2 hour nap –“Siesta cultures” are found in the tropical regions of the world (afternoon is hottest part of the day) –Not found in industrial societies

Sleep Odds & Ends Neural Bases of Sleep –No single structure in the brain serves as a “sleep center” Sleep & waking appears to be regulated by many subcortical structures in the brain –Reticular Formation – in the core of the brainstem, important in sleep »Ascending Reticular Activating System (ARAS) – consists of the afferent fibers running through the reticular formation that influence physiological arousal – projects into many areas of the cortex –Pons –Medulla, Thalamus, Hypothalamus, & Limbic System –Neurotransmitters  Serotonin & GABA

Evolution & Sleep How is sleep adaptive? –1. Sleep evolved to conserve energy »Warmbloodedness requires constant maintenance of high body temps –2. Immobilization associated with sleep reduces the exposure to predators & other dangers –3. Helps organisms restore energy & resources depleted by waking activities

Sleep Deprivation Complete Deprivation Negative effects on mood, cognitive tasks & perceptual-motor tasks When motivated, subjects can still perform well on some of these tasks The effects would be more severe, but most people have a hard time going for LONG periods without sleep Partial Deprivation Sleep experts believe that much of American society chronically suffers from this Impairs attention, reaction time, motor coordination, and decision making

Did you know? Why do we yawn? A yawn is a reflex of inhalation and exhalation that draws more oxygen into the bloodstream. A reflex is a built-in physical reaction that people often do not have control over. A yawn is often associated with a person being tired, but this is not always the cause for a yawn. People yawn for many reasons including stress, boredom, emotion and over-work.

Is Yawning Contagious? If one person yawns, this appears to cause another person to yawn. Researchers have found that % of people who see a picture of someone yawning will yawn themselves. Even reading the word YAWN can make people yawn. Although this “contagious” yawning behavior is not understood, it has been suggested that this could be the result of an unconscious herding behavior — a subtle way to communicate group behavior, such as when a birds follow the behavior of one bird, and all rise together as a whole flock. Maybe a yawn is a signal to the group that it’s time to go to sleep. Or if someone yawns when they’re bored, it may be a sign to change the topic of conversation.