Chapter 4 - Consciousness Flashcards
Consciousness
Our awareness of internal and external stimuli.
Circadian rhythms
24-hour cycles that regulate physiological and behavioral patterns
Wakefulness
High levels of sensory awareness, thought, and behavior.
Sleep
A state marked by low levels of physical activity and reduced sensory awareness
Internal Stimuli
Pain, hunger, thirst, sleepiness, thoughts, emotions
External Stimuli
Vision, touch, sound, taste
Biological rhythms
Regular, cyclic changes in biological processes that occur in living organisms crucial for synchronizing an organism’s internal processes with the
external environment
Ultradian rhythms
Cycles occurring more frequently than once a day
Ex. 90-minute sleep cycles within the overall sleep period
Circannual rhythms
Yearly cycles
Ex. Hibernation in animals, seasonal affective disorder in humans
Infradian rhythms
Cycles occurring less frequently than once a day
Ex. Menstrual cycle
Hypothalamus
Involved in homeostatic processes. In other words, homeostasis in biological system
Suprachiasmatic nucleus (SCN)
The brain’s “clock mechanism,” regulates circadian rhythms
Light-sensitive neurons in retina provide information about the outside world
Pineal gland
Small, pea-shaped gland located in the brain that produces melatonin
Melatonin
A hormone that fluctuates with light levels to help regulate sleep-wake cycle
Jet lag
Disruption of sleep and circadian rhythms caused by rapidly crossing multiple time zones, leading to difficulty adjusting to a new time zone
Insomnia
Difficulty falling asleep, staying asleep, or waking up too early,
resulting in poor sleep quality and daytime impairment
Rotating shift work
Disruption of sleep patterns caused by regularly changing
work shifts, which can lead to sleep problems
Sleep debt
Not getting enough sleep on a chronic basis which can lead to impaired functioning (mental efficiency) and increased sleepiness (low levels of alertness) until the debt is repaid
Sleep deprivation consequences:
- Obesity
- Increased blood pressure
- Increased levels of stress hormones
- Reduced immune functioning
- Difficulty staying awake
- Cognitive and motor functioning impairments
- Irritability
- Distractibility
- Moral judgement impairments
- Hallucinations (if awake 48hr +)
Sleep
A natural, periodic state of rest that is regulated by the body’s homeostatic
needs
Sleep rebound
An increased duration and intensity of sleep following a period of sleep deprivation
Impact of sleep on the Endocrine system
Circadian rhythm
Pineal gland
Pituitary gland
What hormones do the pituitary gland release? And what are their functions?
Growth hormone – Helps body recover and grow
Follicle Stimulating Hormone (FSH) & Luteinizing Hormone (LH) – Regulates reproductive functions
Energy Conservation
By reducing activity, sleep conserves energy
- Negative correlation between energetic demands and time spent sleeping
Memory Consolidation
Sleep supports memory formation and learning
- Learning – Helps processes and consolidate new information
- Skill Improvement – Helps process and refine motor skills
- Emotional Memory – Helps consolidate emotional experiences
Predatory Avoidance
Sleep patterns have evolved to occur during times when the risk of
predation is lower
- Some species sleep during the day
- Nocturnal predators have adapted to nighttime activity
Restoration
Sleep allows the body and brain to repair and rejuvenate
- Physical recovery – Repairs and rebuilds muscle tissue
- Cellular Repair – Enhances protein synthesis
- Immune Function – Helps fight off infection and recover from illness
What measures brain waves?
electroencephalogram (EEG)
Amplitude
The height of the brain waves
Brain wave activity
Electrical patterns or signals produced by neurons in the brain as they communicate
with each other
Frequency
How many waves occur per second (measured in Hertz, Hz)
Rapid Eye Movement (REM)
A sleep stage with rapid
eye movements, vivid dreams, and high brain activity
Non-REM (NREM)
The stages of sleep excluding
REM, including light and deep sleep.
Spindles
Brief bursts of high-frequency brain activity that may be important for learning and
memory
K-complex
A very high amplitude (spike) pattern of brain activity that can occur with environmental
stimuli
Delta Waves
- Slow (low frequency) and high (high amplitude) waves
- Slower heart rate & respiration
- Difficult to wake someone up
REM
- Waves similar to activity pattern when awake
- Vivid dreams
- Marked by rapid eye movement
- Sleep paralysis, paralysis of muscle systems
- “Paradoxical sleep”
REM rebound
If an individual is deprived of REM sleep, they will spend more time in TEM sleep to
recoup lost time
- May be an adaptive response to stress
Sigmund Freud’s Dream Content Distinctions
Latent content & Manifest content
Latent Content
The underlying, hidden meaning of the dream
Manifest Content
The actual storyline, images, and events that you
remember upon waking
Founder of “Collective Unconscious”
Carl Jung
Activation-synthesis theory of learning
Dreams are a byproduct of brain activity rather than a direct manifestation of unconscious desires or conflicts
- Brain is trying to make sense of (“synthesize”) the neural activity (“activation”) that’s
happening - Brain builds a virtual reality that builds the neural pathways to help us in wakefulness
Collective unconscious (in the context of dreams)
Dreams contain symbols
with meanings that are similar for all people regardless of culture or location
Rosalind Cartwright’s Perspective
Dreams simply reflect life events that are important to the dreamer
Alan Hobson’s Theory
Activation-synthesis theory of learning
Insomnia
A consistent difficulty in falling or staying asleep
- One criteria for diagnosis: Symptoms must last for at least 3 x a week
in one month’s time - The most common sleep disorder
- A self-perpetuating cycle
- Contributing factors: Age, drug use, exercise, mental status, bedtime
routines
Treatments for insomnia
- Limiting caffeine intake
- Increasing physical exercise
- Over-the-counter (OTC) sleep medications
- WARNING: Can cause dependency and alter sleep cycle, increasing insomnia
- Cognitive-behavioral therapy (CBT)
Parasomnia
Abnormal behaviors, movements, emotions,
perceptions, or dreams that occur during sleep or while falling asleep
Cognitive-behavioral therapy (CBT)
A type of psychotherapy that focuses on cognitive processes and problem behaviors
Examples of Parasomia
- Sleepwalking
- REM sleep behavior disorder (RBD)
- Restless leg syndrome
- Night terrors
Sleepwalking (Somnambulism)
Sleeper engages in relatively
complex behaviors ranging from wandering about to driving!
- Happens during NREM Stage 3 (Deep Sleep)
- Often have eyes open but are not responsive
- It is genetic; it runs in families
- It is most common in children (4 – 8)
- Homicidal sleepwalking?!
Treatments for Sleepwalking
- Anxiety meds & antidepressants (success rate questionable)
- Addressing sleep-related breathing problems
- Improving sleep hygiene
- Scheduled awakenings
REM sleep behavior disorder (RBD)
Incomplete muscle
paralysis, causing people to act out vivid and often violent
dreams during REM
* Kicking, punching, scratching, yelling, behaving like an animal
* Associated with Parkinson’s and other neurodegenerative diseases
* Potential aid in diagnosis?
Treatment for REM sleep behavior disorder (RBD)
Anxiety medication & making environment safe
Restless leg syndrome
Uncontrollable urge to move the legs,
often accompanied by uncomfortable sensations like itching,
tingling, or aching
- Very common
- Associated with various medical diagnoses, like chronic kidney disease and
diabetes
Treatments for Restless leg syndrome
Anxiety meds, anticonvulsants, opiates
Night terrors
Episodes of intense fear, screaming and flailing
during NREM (usually in Stage 3)
- Unlike nightmares, the person does not usually remember details of the event
- Person is disoriented and hard to wake up fully
- Common in children, lessen with age
Treatment for night terrors
Unnecessary unless underlying medical/psychological condition
Sleep Apnea
Episodes during which a sleeper’s breathing stops
- Person may not be aware of repeated disruptions, but will experience
increased levels of fatigue - More common in overweight people and associated with loud snoring
- May exacerbate cardiovascular disease
Types of Sleep Apnea
Obstructive sleep apnea (OSA) & Central sleep apnea (CSA)
Obstructive sleep apnea (OSA)
Individual’s airway becomes blocked
- Relaxed throat muscles and tissues cause obstruction
Central sleep apnea (CSA)
Disruptions in signals sent from the brain cause periods of
interrupted breathing
- No obstruction, brain fails to send signals to the muscles that control breathing
Treatments for sleep apnea. What do they do?
Continuous positive airway pressure (CPAP): A device that includes a mask that fits over the sleeper’s nose
and mouth, which is connected to a pump that pumps air into the person’s airway, forcing them to remain
open
Expiratory positive airway pressure (EPAP): A device that includes a small, valve-like mask worn over the nose
which provides pressure during exhalation
Sudden infant death syndrome (SIDS)
A sudden and
unexplained death of an otherwise healthy infant, usually during
sleep
- Infants younger than 12 months at highest risk
- Boys have a higher risk than girls
Risk factors of SIDS
premature birth, smoking within the home,
hyperthermia (abnormally high body temperature)
Narcolepsy
Excessive daytime sleepiness and sudden,
uncontrollable episodes or sleep
- Associated with cataplexy: A sudden and brief loss of muscle tone
- May include vivid, dream-like hallucinations
- Often triggered by stets of heightened arousal or stress
- Episodes typically last between 1 minute – 30 minutes
Treatment for Narcolepsy
Psychomotor stimulant drugs (drugs that promote
increased levels of neural activity)
Altering States of Consciousness
- Substance use and abuse
- Hypnosis
- Meditation
Stage 1 sleep
a transitional phase between wakefulness and sleep (drifting off to sleep).
Alpha and Theta Waves
Stage 2 sleep
the body goes into a state of deep relaxation.
Theta waves & Sleep spindles & K complexes
Stage 3 sleep
deep sleep or slow-wave sleep. Delta waves
