Chapters 4- Flashcards
Consciousness
Awareness of internal and external stimuli such as feelings of
hunger and pain or detection of light.
Wakefulness
High levels of sensory awareness, thought, and behavior
Circadian rhythm
Biological rhythm that occurs over approximately 24 hours.
Suprachiasmatic nucleus (SCN).
Influences Hypothalamus and petuitary system to control the biological clock. Light sensitive.
What part of the brain releases Melatonin
Melatonin is released by the pineal gland
Jet lag
Symptoms resulting from the mismatch
between our internal circadian cycles and our
environment.
Sleep Dept
Result of insufficiant sleep on a chronic basis
Sleep Rebound
A sleep-deprived individual will tend to take a shorter time to fall
asleep during subsequent opportunities for sleep.
Symptoms of Sleep Deprivation
Irritablility, cognitive impairment,
Sleep needs by age
Children need more sleep then adults
What is sleep?
Sleep is a state marked by relatively low physical activity and a reduced sense of awareness.
Why do we sleep - Adaptive Function (Evolutionary Hypotheses) Theory
Sleep is essential to restore resources that are expended during the day.
- Sleep is an adaptive response to predatory risks, which increase in darkness.
There is little evidence to support these explanations.
Why do we sleep - Cognitive Function theory
Focuses on sleeps importance for cognitive function and memory formation.
- Research shows that sleep deprivation results in disruptions in cognition and
memory deficits.
- These impairments become more severe as the amount of sleep deprivation
increases.
- Slow-wave sleep appears to be essential for effective memory formation.
Benifits of sleep
Maintaining a healthy weight, lowering stress levels, improving mood, increased
motor coordination as well as many benefits related to cognition and memory
formation.
What are Alpha waves?
relatively low
frequency, relatively high
amplitude, synchronized.
What are Theta waves?
low frequency,
low amplitude.
What are delta waves
low frequency,
high amplitude,
desynchronized.
What are beta waves
the waves when you are awake
Stage 1 of sleep
Transitional waves (alpha waves) about 5 minutes
Stage 2
10-15 minutes Theta waves
- Characterized by the appearance of
both sleep spindles and K-
complexes.
Sleep spindles – rapid burst of high
frequency brainwaves.
K-complexes – very high amplitude
pattern of brain activity.
STAGES 3 AND 4 of sleep
Known as slow-wave sleep.
- less then 50% Delta waves.
- Respiration and heart rate slow down further.
How long is a sleep cycle?
Roughly 90 minutes
RAPID EYE MOVEMENT (REM) Stage 5
Rapid eye movements.
- Paralysis of voluntary muscles.
- Dreams.
- Brain waves are similar to those seen during wakefulness.
What is a hypnogram?
A hypnogram is a diagram of the stages of sleep as they occur during a period of
sleep.
Sycodynamic theory
Saw dreams as a way to gain access to the unconscious.
• Manifest content – the actual content of the dream.
• Latent content – the hidden meaning of the dream
Carl Jung: (neofruidian)
Collective unconscious – theoretical repository of information shared by all
people across cultures.
Lucid dreams
Certain aspects of wakefulness are maintained during a
dreaming state. A person becomes aware that they are dreaming.
Basal forebrain
can induce sleep when stimulated
Insomnia
Defined by difficulty falling or staying asleep - for at least 3 nights a week for at least one month’s time.
The most common sleep disorder.
Man be associated with symptoms of depression.
Treatment for Insomnia
- Stress management techniques.
- Changes in problematic behaviors that could contribute to insomnia.
- Cognitive-behavioral therapy which focuses on cognitive processes and problem behaviors.
PARASOMNIA
involve unwanted motor behavior/experiences throughout the sleep cycle.
Sleep Walking
- Occurs when the muscle paralysis associated with REM sleep does not occur.
- Includes high levels of physical activity during REM sleep.
- Often treated with Clonazepam (an anti-anxiety medication).
Restless leg syndrome:
- Involves uncomfortable sensations in the legs when trying to fall asleep that are
relieved by moving the legs. - Can be treated with a variety of medications.
- Usually occurs during slow-wave sleep.
REM sleep behavior disorder:
- Sleeper experiences a sense of panic and may scream or attempt to escape.
- Occur during NREM sleep.
SLEEP APNEA
Occurs when individuals stop breathing during their sleep, usually for 10-20 seconds
or longer.
Repeated disruptions in sleep lead to increased levels of fatigue.
Common in people that are overweight.
Obstructive Sleep Apnea
airway becomes blocked and air is prevented from entering the lungs.
Centeral Sleep Apnea
CNS fails to initiate breaths.
NARCOLEPSY
Involves an irresistible urge to fall asleep during waking hours.
Often triggered by states of heightened arousal or stress.
Shares many features of REM sleep including:
Cataplexy – loss of muscle tone while awake or in some cases complete paralysis
of the voluntary muscles.
Hypnagogic hallucinations - vivid, dream-like hallucinations.
Treatment – psychomotor stimulant drugs.
Physiological dependence
involves changes in normal bodily functions and
withdrawal upon cessation of use.
Psychological dependence
emotional need for the drug.
Tolerance
occurs when a person
requires more and more of a drug to
achieve effects previously experienced at
lower doses; linked to physiological
dependence.
Withdrawal
negative symptoms
experienced when drug use is
discontinued.
Depressants
drugs that suppress the central nervous system activity.
- Alcohol
- Barbiturates (anticonvulsant medication)
- Benzodiazepines (anti-anxiety medication)
Stimulants
Increase overall levels of neural activity. Increases dopamine
- Cocaine
- Amphetamine
- Cathinones (i.e., bath salts)
- MDMA
-Nicotine
Opioids
Derived from opium
- Heroine
- Morphine
- Methadone
- Codeine
Hallucinogens
Distorts reality
LSD, PCP
Sensory Receptors
Specialized neurons that respond to specific types of stimuli
Sensation
occurs when sensory receptors detect sensory stimuli.
Sensory Systems
Vision
- Hearing (audition)
- Smell (olfaction)
- Taste (gustation)
- Touch (somatosensation)
- Balance (vestibular sense)
- Body position (proprioception)
- Movement (kinesthesia)
- Pain (nociception)
- Temperature (thermoception)
Absolute threshold
minimum amount of stimulus energy that must be present for the stimulus to be detected 50% of the time.
Subliminal messages.
messages presented below the threshold of conscious
awareness
Just noticeable difference
the minimum difference in stimuli required to
detect a change or a difference between stimuli.
Perception
way that sensory information is interpreted, organized, and consciously experienced.
Bottom-up processing
system in which perceptions are built from
sensory input.
Top-down processing
interpretation of sensations is influenced by
available knowledge, experiences, and thoughts.
Sensory adaption
not perceiving stimuli that remain relatively constant over
prolonged periods of time.
- For example, when you first enter a quiet room you may hear the clock ticking.
Over time you become unaware of the ticking. The ticking is still affecting sensory
receptors but you are no longer perceiving the sound.
Inattentional blindness
Failure to notice something
that is completely visible
because of a lack of attention.
Factors affecting perception
Motivation
Signal detection theory – change in stimulus detection as a function of current mental state.
Beliefs, values, prejudices and expectations
- People who hold positive attitudes towards low-fat foods are more likely to rate foods with low-fat labels as tasting better than people with less positive attitudes about low-fat products.
Life/Cultural experiences
- One study found that people from Western cultures (where there is a perceptual
context of buildings with straight lines) were more likely to experience certain types of visual illusions, like the Muller-Lyer illusion, than individuals from non-western
cultures (where they are more likely to live in round huts).
Amplitude and wave length
center to crest, crest to crest
Frequency
Number of waves