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Chapter 4

States of Consciousness

Understanding Consciousness
Understanding Consciousness
Consciousness involves an individual's awareness of internal and external stimuli. Internal stimuli might include feelings of hunger or emotional ...
High-Level and Low-Level Awareness
High-Level and Low-Level Awareness
Higher levels of consciousness involve controlled processes that require focused effort on complex tasks, driven by the brain's ability to think, ...
Altered States of Awareness
Altered States of Awareness
Altered states of consciousness can be substance-induced, or can be triggered by illness, meditation, and hypnosis. The use of substances, such as ...
Subconsciousness and No Awareness
Subconsciousness and No Awareness
Subconscious awareness processes information automatically without conscious effort. Subconscious problem-solving during breaks is called incubation, ...
Understanding Sleep
Understanding Sleep
Sleep is a naturally occurring state characterized by reduced physical activity and sensory awareness. Sleep is regulated by brain regions, specifically ...
Insufficient Sleep and Sleep Deprivation
Insufficient Sleep and Sleep Deprivation
Insufficient sleep is when an individual receives less than adequate sleep on a regular basis, gradually impairing alertness, reducing focus, increasing ...
Stages of Sleep
Stages of Sleep
Sleep progresses through stages, starting with non-rapid eye movement or NREM, and transitioning to rapid eye movement or REM. Each stage is characterized ...
Dreaming
Dreaming
Freud viewed dreams as windows to the unconscious, revealing hidden desires and fears. He introduced two key concepts to understand dreams — ...
Lucid Dreaming
Lucid Dreaming
Lucid dreaming occurs when an individual becomes aware that they are dreaming. This awareness allows the individual to choose how to interact with the ...
Insomnia
Insomnia
Insomnia is a common sleep disorder that involves symptoms such as difficulty falling asleep, frequent awakenings, or waking too early. Insomnia is ...
Sleepwalking and Sleep Talking
Sleepwalking and Sleep Talking
Sleepwalking, also known as somnambulism, occurs during stages 3 and 4 of deep sleep when individuals are least likely to be dreaming. During sleepwalking ...
REM Sleep Behavior Disorder
REM Sleep Behavior Disorder
During REM sleep, most voluntary muscles, such as those in the arms and legs, are temporarily paralyzed to prevent acting out dreams. REM Sleep behavior ...
Restless Leg Syndrome and Night Terrors
Restless Leg Syndrome and Night Terrors
Restless leg syndrome is a neurological condition causing an uncontrollable urge to move the legs due to sensations such as itching, throbbing, crawling, ...
Sleep Apnea
Sleep Apnea
Sleep apnea is a sleep disorder in which breathing repeatedly stops, with each pause potentially lasting for at least 10 seconds. Sleep apnea primarily ...
Narcolepsy
Narcolepsy
Narcolepsy is a sleep disorder characterized by uncontrolled daytime sleepiness, with individuals entering REM sleep directly. The urge to sleep can be so ...
Nightmares and Night Terrors
Nightmares and Night Terrors
Nightmares are distressing dreams that occur during REM sleep, often waking the individual and leaving vivid memories upon waking. Nightmares can affect ...
Substance Use Disorders Affecting Sleep
Substance Use Disorders Affecting Sleep
Substance use disorders involve repeatedly consuming more of a substance, such as alcohol, prescription medications, or caffeine, than intended, despite ...
An Overview of Psychoactive Drugs
An Overview of Psychoactive Drugs
Psychoactive drugs act on the nervous system and brain functions and alter consciousness, impacting mood, perception, and behavior. These drugs are ...
Depressants
Depressants
Depressants are a class of drugs that slow down brain activity. They work by increasing the activity of inhibitory neurotransmitters like ...
Stimulants
Stimulants
Drugs that increase neural activity and boost dopamine levels in the brain, making their consumption highly addictive, are called stimulants. There are ...
Hallucinogens and Psychedelics
Hallucinogens and Psychedelics
Hallucinogens are psychoactive drugs that alter an individual's perception of reality, creating unreal visual images. Marijuana and lysergic acid ...
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