Lecture Consciousness Part 1

Introduction to Psychology

• Focus on states of consciousness

Understanding Consciousness

• Definition: Awareness of internal and external stimuli (e.g., heat, sound, hunger, emotions)

• Origin of Awareness: Emerges from the brain, raising questions about complexity vs. physical structure of the brain

• Scientific Mystery: How consciousness arises from brain activity remains an open question.

Continuum of Consciousness

• Consciousness exists on a continuum of arousal and awareness:

  • Highly Alert States: WAKE

  • Decreased Awareness: LOCKED-IN SYNDROME, DROWSINESS

  • Sleep States: REM SLEEP, LIGHT SLEEP, DEEP SLEEP

  • Minimally Conscious State

  • Lowered Arousal: GENERAL ANESTHESIA, VEGETATIVE STATE, COMA

Biological Rhythms

• Definition: Internal rhythms of biological activity

• Types of Biological Rhythms:

  • Infradian Rhythms: Cycles longer than 24 hours (e.g., menstrual cycle, Seasonal Affective Disorder)

  • Ultradian Rhythms: Cycles occurring more than once a day (e.g., eating, performance)

  • Circadian Rhythm: 24-hour biological cycles (e.g., sleep-wake cycle)

Menstrual Cycle Overview

• Diagram indicating the phases of the menstrual cycle:

  • 01-07: Period

  • 14: Ovulation

  • Hormones involved: FSH, E2, LH, PG

Ultradian Performance Rhythm

• Performance fluctuates due to stress and arousal levels:

  • Top performance can alternate between high and low depending on breaks (20-minute recovery)

  • Rhythm visible across various tasks and activities

Circadian Rhythm and Sleep Patterns

• Sleep/Wake Cycle: Regulated by the brain's SCN (suprachiasmatic nucleus) responding to light levels

  • Light Indicator: More light signals wakefulness, less indicates sleep

  • Melatonin: Produced by the pineal gland, regulates sleep patterns

Stages of Sleep

• Sleep divided into two general phases:

  • REM (Rapid Eye Movement) Sleep:

    • Characterized by darting eye movements and brain waves similar to wakefulness

  • Non-REM Sleep (NREM):

    • Subdivided into three stages:

      • Stage 1: Transition from wakefulness to light sleep

      • Stage 2: Light sleep with decreased awareness of surroundings

      • Stage 3: Deep sleep necessary for feeling refreshed

Sleep Characteristics

• K-complexes: Reflect brain response suppression to non-threatening stimuli, aid in memory consolidation

• Sleep Spindles: Indicate learning and memory activity, comparable to wakefulness in REM

Importance of Sleep

• Theories on sleep necessity:

  • Adaptive Function: Conserves energy or enhances safety (limited support)

  • Cognitive Function: Essential for memory formation and retention

    • Sleep aids memory consolidation of facts and skills, especially during light and REM sleep

Effects of Sleep Deprivation

• Negative impacts on academic performance and cognitive functions

• Lack of sleep creates lasting impairments in various cognitive domains

  • Recovery may take time, indicating the severity of sleep deprivation effects

Sleep and Positive Emotions

• Sleep improves memory recall for positive experiences, enhancing emotional balance

• Promotes a favorable emotional climate favoring positive over negative emotions

Theories of Dreaming

• Unexplained Phenomenon: Various theories attempt to explain why we dream:

  • Activation-synthesis Theory: Dreams arise from brain impulses during sleep

  • Continual-activation Theory: The unconscious processes procedural memories during REM

  • Threat-simulation Theory: Dreams simulate threats for better preparedness

  • Expectation-fulfillment Theory: Dreams discharge unexpressed emotional arousals

Sleep Disruptions

• Factors affecting sleep cycles:

  • Puberty: Influences melatonin levels and sleep cycle

  • Rotating Shift Work: Alters sleep patterns dramatically

  • Jet Lag: Results from time zone travel, causing internal cycle misalignment

  • Sleep Debt: Chronic lack of sufficient sleep, impacting health and function

Importance of Sleep for Adolescents

• American Academy of Pediatrics' Statement:

  • Insufficient sleep in adolescents is a public health issue affecting health and safety

  • Earlier school start times contribute negatively to adolescent sleep, urging changes for better outcomes

  • Advocated to optimize sleep for improved health and academic performance

Consequences of Insufficient Sleep

• Physiological and psychological effects include:

  • Irritability, cognitive impairments, increased heart disease risk, and memory lapses

  • Severe problems like hallucinations, ADHD-like symptoms, and impaired immune function

  • Risk factors for obesity, diabetes, and other health issues

Common Sleep Disorders

• Insomnia: Difficulty in falling/staying asleep; treatment includes exercise, limiting stimulants, and CBT

• Sleep Apnea: Breathing interruptions during sleep; treated with CPAP machines

• Narcolepsy: Sudden daytime sleepiness; managed with amphetamines

Next Topic

• Review of alterations in consciousness and their implications.