Chapter 5 Flashcards
Endocrine System
Collection of glands which produce and releases hormone
Hormones
-Chemicals secreted into the bloodstream that travel through the body
-Less effective than neurotransmitters
-Contribute to homeostasis
Hypothalamus
Brain structure regulating biological needs and motivational systems
Pituitary Gland
-Receives input from hypothalamus
-Master gland that produces hormone and commands hormone production from other glands in endocrine system
-Ex adrenal gland (stress), pineal gland(sleep/wake cycle)
-Produces endorphins (pain reduction /pleasure) and testosterone
Consciousness
A person’s subjective awareness
-thoughts
-perceptions
-experiences
-self awareness
Circadian rhythms
-Internally driven daily cycles
-Affect physiological and behavioural processes
•sleep/wake
•hunger
•concentration
Circadian Rhythm (How it works)
Retina stimulated by light
Sends environmental info to SCN
Pineal Gland
Releases Melatonin
Hypothalamus (Control Center)
Entrainment
Biological rhythms synchronizing to external cues
Ex Light, temperature, clocks
Endogenous Rhythms
Biological rhythms generated by body
Independent of external cues
Polysomnography
Set of objective measurements used to examine physiological variables during sleep
-respiration, body temp, muscle activity
Electroencephalogram
-Measures excitatory and inhibitory activity in groups of neurons in brain
-Produces a waveform
•frequency and amplitude
Stages of Sleep (Awake)
Beta Waves:
high frequency 15-30 Hz
low amplitude
wakefulness
Alpha Waves:
lower frequency 8-14 Hz
daydreaming, meditating, falling asleep
Stages of Sleep (1-2)
Theta Waves (1-2):
Lower frequency 4-8 Hz
Higher amplitude
Breathing, blood pressure, heart rate decrease
Still sensitive to external stimuli
Sleep spindles (2)
Clusters of high fre low amp waves
K complexes (2)
Small groups of large amp waves
2 important for memory formation? Theory
Stages of Sleep (3-4)
Delta Waves
-low frequency <3 Hz
-high amplitude
-deep sleep
REM(Rapid Eye Movement)
Quickening brain waves
Inhibited body movement
Rapid eye movements
Approx 20-25% of total sleep
Restore and Repair Hypothesis
Our bodies need to restore energy levels and repair any wear and tear from day
Lack of sleep associated with cognitive decline,emotional disturbances, impaired immune system
Sleeping helps clear waste products and excess proteins in the brain
Preserve and Protect Hypothesis
Sleep is important to preserve energy and protect organism from harm
Prey sleep in safe locations when predators awake and hunting
Higher food chain animals sleep more
Sleep Deprivation
Occurs when individual cannot or does not sleep
Related to internal and external factors
Impaired coordination (0.07 blood alcohol level-1 night)
Sleep Displacement
When individual does not sleep at normal time
Can be related to external and internal factors
The Psychoanalytical Approach (Sigmund Freud)
Dreams unconscious expression of wishes
Manifest Content (literal content)
Latent Content (meaning)
The Activation-Synthesis Hypothesis
Dreams arise from brain activity
Specifically excitatory message bursts in Pons
Pons> explains REM
> stimulation of occipital+temporal lobes can produce sights and sounds
Different regions of cortex attempt to make sense of this info: Synthesis
(Frontal lobe key role in story bridging)
Insomnia Disorder
Extreme lack of sleep (17% Canadians)
Onset, maintenance, terminal
Often related to other conditions
Nightmares
Vivid and disturbing dreams occurring during REM sleep (85-95% of adults)
Night Terrors
Intense panic and arousal inducing heightened emotional state (1% of adults, 1-6% of children)
Occurs during non-REM sleep
REM behaviour disorder
No restricted movement during REM
Acting out content of dreams
Somnambulism
Wandering/ Other activities while asleep
During non-REM sleep
Prevalent in childhood
Sexomania
Sexual activity while asleep
Sleep Apnea
Obstruction of air flow causing temporary inability to breathe
Treatments include:
Dental devices holding head in pos
Weight loss
CPAP devices
Can be caused by brain’s failure to regulate breathing
-Medulla> Responsible for controlling chest muscles while breathing
Narcolepsy
Extreme daytime sleepiness and sleep attacks
Few seconds to few mins
Immediate transition to REM
Can be triggered by intense emotion
Medication can treat
Associated with lower levels of orexin
-hormone from hypothalamus to maintain wakefulness
Hypnosis
Induces heightened state of suggestibility
-ideomotor suggestions
-challenge suggestions
-cognitive-perceptual suggestions
Dissociation Theory
Conscious divided into 2 parts
Low level system with perception and movement
Executive system to evaluate and monitor behaviours
Hypnotic suggestions bypass executive system
-reduced activity in frontal lobe
Social Cognitive Theory
Emphasizes degree beliefs and expectations contribute to suggestibility
People conform to what they expect
Hypnosis (More)
Sometimes pairs with other psychotherapies
CBT + hypnosis = cognitive hypnotherapy
Potential for pain treatment (60-75% report reduced pain)
Connections involving anterior Cingulate gyrus differ between hypnotizable and non hypnotizable
Mind Wandering
Unintentional redirection of attention
Default Mode Network
-Network of brain regions most active when awake but no external stimuli
Frontoparietal Network
-goal directed thinking and attention control
Mind wanderers think about future more
Pons
Relay of neural impulses
Control of voluntary movement
Transfer of info between the medulla and Cortex
Locked In Syndrome
Patient is aware and awake but unable to move
Damage to pons?
MCS (minimally conscious state)
Able to show some behaviours, even on inconsistent basis
Some activity in higher order sensory and cognitive regions
Vegetative state
Minimal to not consciousness
Eyes may be open
Developed sleep wake cycles
Caused by extensive brain damage?
Coma
Complete loss of consciousness
Damages to brainstem?
-suppressed reflexes (pupil dilation/constriction)
-widespread damage to both hemispheres
-2-4 weeks to recover
Brain Death
Brain and brain stem no longer function
Brainstem regions for basic life functions don’t work
Case Study 1
Vegetative state
Imagine Tennis- Activity in movement brain areas
Imagine House- Spacial network (para hippocampal gyrus and parietal lobe)
Case Study 2
Used tennis house technique for yes no communication
Agonists
Enhance or mimic neurotransmitter actions
Antagonists
Inhibit neurotransmitter activity by blocking receptors or preventing transmitter synthesis
Dopamine
Reward, pleasurable feelings
When released in nucleus accumbens and ventral tegmental area, gives high
Pleasure reinforces drug taking behaviour
Anticipation can release dopamine
Short Term
More powerful in novel settings
Subsequent uses can make more potent
Expectations influence effects
Long term
Tolerance
-caused by brain attempting to maintain stable levels of neurotransmitters
Down regulation> decrease in receptor sensitivity in synapse
Dependence
Physical dependence
-need to take drug to ward off withdrawal
Psychological dependence
-emotional need for drug
Biopsychosocial model
Psychoactive drugs
Affect thinking, perception and emotion
Stimulants
Speed up activity of nervous system, enhance wakefulness and alertness
Caffeine
Adenosine antagonist binds to adenosine receptors, blocking them
Temporarily increases energy levels and alertness by stimulating adrenal glands
Cocaine
Blocks dopamine reuptake (dopamine agonist)
Can influence seratonin (mood appetite sleep) and norepinephrine(memory, attention, sleep, mood) levels
Amphetamines
Prescription drugs (Ritalin, Provigil)
-Methamphetamine
> stimulates dopamine release from presynaptic cells (dopamine agonist)
Can cause structural abnormalities in frontal lobe
Ecstasy/MDMA
Stimulant with hallucinogenic effects
Blocks seratonin reuptake (seratonin agonist)
Can help with ptsd
Hallucinogens (Psychedelics)
Produce perceptual distortions
Low likelihood for dependence
Distortions May be visual, auditory, tactile
Can occur in nature (psilocybin, mescaline)
Powerful emotional experiences
LSD
Lab made synthetic drug that triggers unusual sensory experiences
Increase activity in visual brain areas, but visual stimuli also activate non visual areas
Reduced connection between temporal and parietal lobes
-losing oneself
Can treat anxiety with terminal illnesses
Ketamine
Developed as short term surgical anesthetic
Induces dream like states, memory loss, dizziness, confusion, distorted sense of body ownership
Blocks glutamate receptors(direct glutamate antagonist)
Glutamate
-primary excitatory neurotransmitter, memory, ANS system reactions
1 hour
DMT
In certain tree barks, toad skin surface, human nervous system
Intense spiritual experiences and connectiveness
Can reduce addiction to tobacco and alcohol
1 hour
Salvia Divinorum
Herb in central and South America
Intense short lived hallucinations when smoked or chewed
Dissociative experiences
1 hour
Opiates (Narcotics)
Reduce pain and induce immediate euphoria, high dependence
Eg. heroin, fentanyl, oxycodone
Bond to endogenous endorphin receptors
Endorphins
-neurotransmitters that reduce pain and produce pleasurable feeling
Sedatives
Depress activity of central nervous system, high dependence
Eg. Barbituates> early medicine to treat anxiety and promote sleep
-can shut down brainstem functions
Benzodiazepines (Xanax, Ativan, Valium)
-increase GABA activity(GABA agonist)
-impair attention, reaction time, coordination
GABA
-primary inhibitory neurotransmitter, lower arousal/anxiety, facilitates sleep
Alcohol
Moderate to high dependence
Stimulates GABA receptors, then opiate and dopamine receptors
Increased consumption leads to increased GABA
Marijuana
Combined hallucinogenic, stimulant and relaxing effects, low dependence
Anandamide agonist
THC compound in marijuana mimics anandamide and binds to cannabinoid receptors to induce euphoria, relaxing, pain reduction, sensory experience, appetite
Good for cancer
Marijuana effects
Impares short and long term memory and executive functions
Decreased frontal lobe activity (memory retrieval)
Cannabinoid receptors found throughout hippocampus and medial frontal lobes
Long term use associated with reduced grey and white matter in memory regions of temporal lobe
Marijuana and teenage brain
Impares frontal lobe development and disrupts white matter pathways in brain
Impaired cognitive abilities such as memory and executive functioning
