PSYC 1315 1st Edition Lecture 15Last LectureState of consciousness Current Lecture State of consciousness Biological Clocks Brain structures that schedule rhythmic variations in bodily functions by triggering them at the appropriate times Setting our biological clocks: ¡ The environment helps Why do we need sleep? Adaptive Evolutionary Function ¡ safety¡ energy conservation/efficiency Restorative Function¡ body rejuvenation & growth Brain Plasticity¡ enhances synaptic connections ¡ memory consolidation Sleep Deprivation Chronic sleep deprivation results in... ¡ decreased alertness and cognitive performance. ¡ inability to sustain attention. ¡ less complex brain activity. ¡ adverse effects on decision making. Characteristics of Sleep EEG: monitors the electrical activity of the brain Note: ¡ Height (amplitude)¡ Frequency (cycles)¡ Regularity (smoothness) Stages of Sleep Stage 1¡ Theta waves¡ Drifting thoughts, slow breathing Stage 2¡ Sleep spindles¡ K complexes¡ Asleep but may respond to some external signals Stages 3 and 4¡ Deeper sleep state¡ Delta activity– more synchronized slow-wave patterns ¡ Tough to arouse; lack responsiveness if woken REM sleep¡ 70 – 90 minutes into sleep cycle¡ Rapid eye movement¡ Vivid dreams; if awoken usually remember (80%) ¡ “Paradoxical” sleep Functions of Sleep Repairing and restoring ¡ Our brains need ‘down time’ ¡ Sleep deprivation leads to inability to perform complex task ¡ Isn’t strong evidence à the more you do during the day DOES NOT lead to length of sleep that night Survival value¡ Increases the likelihood that we will survive (won’t go wandering in thedark) ¡ Animal evidence¢ Vision-based predators ¢ Large animals Sleep deprivation Symptoms: ¡ Slurred speech ¡ Declines in mental ability ¡ Even development of paranoia/ hallucinations Animals:¡ Can’t regulate internal functioning ¡ 3 weeks à
View Full Document
Unlocking...