Physiological Psychology Lecture #5 Flashcards
Adenosine
Inhibitory.
1. Astrocytes store glycogen for “emergency energy”.
- Adenosine is by-product (ATP –> Adenosine)
- Accumulation of adenosine produces increase delta sleep.
- Adenosine increases steadily during day producing sleep feelings at night.
- Caffeine blocks adenosine receptors
What does sleep deprivation lead to?
Decrease in glycogen stores and increase in adenosine which leads to sleepiness.
Histamines
Drugs that prevent synthesis of histamine cause decreased wakeful sensation and increase sleepiness.
- Histamines activate the release of acetylcholine.
Acetylcholine
3 Groups of Ach Neurons:
- 1 in Hippocampus
- 2 located in the pons and forebrain
Cortical Desynchrony
- Low voltage mixed frequencies.
- Hallmark of REM sleep
- Contributes to belief that REM sleep may play an important role in facilitating synaptic plasticity of recently acquiring memory traces.
Serotonin
- Play a role in activation behavior.
- Low during REM sleep = limited movement.
Norepinephrine
Produces arousal and sleeplessness.
- Mediated by the locus coeruleus in the pons.
- Increase locus coeruleus firing = increase vigilance/focus
Orexin
- Secreted by hypothalamus
- Stimulates other neurons to promote alertness and energy metabolism in response to stress in the environment.
- High during alert or active waking, especially exploratory activity.
Melatonin
- Produced by the pineal gland in response to evening/darkness about 2 hours before normal sleep time.
- Serotonin is converted into melatonin.
Insomnia
- Effects 30% of adults.
- 40% of women, 30% of men
- High comorbidity rate with chronic medical conditions.
- Chronic use of sleep-promoting drugs can cause rebound insomnia.
Primary Insomnia
Difficulty falling asleep after going to bed or after awakening during the night.
Secondary Insomnia
Inability to sleep due to another mental or physical condition.
Narcolepsy
- Orexin-Related Neurological d/o
- REM related symptoms occur inappropriately.
- > 85% orexin producing neurons.
- Hereditary component.
Sleep Attacks
Overwhelming urge to sleep.
- Triggered under boring and monotonous conditions.
- Lasts 2-5 minutes
- Wake up refreshed
Cataplexy
Sudden muscle weakness/paralysis.
- Triggered by strong emotional reaction to physical exertion.
- Remain fully conscious.
- Loss of muscle control due to massive inhibition of motor neurons in spinal cord.
Sleep Paralysis
Inability to move before onset of sleep or waking.
Narcolepsy Treatment
Modafinil, methylphenidate, SSRIs
REM Sleep Behavior Disorder
Lack of muscle paralysis during REM can lead to acting out dreams.
- Can be comorbid with narcolepsy.
- Typical onset 60+ years
- Believed to be neurodegenerative.
Treatment: Clonazepam.
Sleep Apnea
Difficulties sleeping and breathing at the same time.
- Wake up gasping for air and decrease slow wave activity.
Obstructive Sleep Apnea
Due to narrowing of airway (obesity, enlarged tonsils, hormonal changes)
Central Sleep Apnea
Brain does not signal need to breath.
Untreated Sleep Apnea
- Significant deficits in attention, memory, and executive functions.
- In kids, 2.5x risk of behavioral problems.
How is sleep apnea treated?
Treated vis CPAP, BiPAP
Alzheimer’s Disease
Disordered Cardiac Rhythm
- Body temperature lowers between 9-noon (rather than 4-5am)
Schizophrenia
Disordered Cardiac Rhythm
- Melatonin production lages (2-3am)
- Rhythms collapse in some patients.
- Pattern can persist despite improvement of sleep quality and quality with antipsychotic agents.
- Treatment with Ramelteon improved sleep w/o negative benzo side effects.
Depression
40-60% report sleep problems.
Suicide
Sleep deprivation independent risk factor.
Sleep D/O Post-TBI
- Up to 80% report sleep problems after injury.
- Female sex, Black race, history of TBI, and psychiatric history were all associated with severe persistent insomnia.
- Poor sleep = poorer recovery trajectory due to increased risk for mood d/os, ongoing cognitive deficits, and neurodegeneration.
Sleep and Learning
- All-nighter can cause up to 40% decrease in brain activity.
- Taking a nap following studying and class–consolidation of learning.
Jame’s Lange Theory of Emotion
Stimulis –> Physiological Arousal –> Emotional Response
Cannon-Bard Theory of Emotion
Stimulus –> emotional response/physiological arousal
Scachter-Singer Theory
Stimulus –> Phsyiological Arousal –> Cognitive Appraisal –> Emotional Response
Fear
Amygdala–core processor of conscious and unconscious fear and value.
- Plays a key role in learning conditioned responses towards aversive stimuli.
Episodic Memory
Long term memory that involves conscious recollection of previous experiences.
Long Term Potentiation
Process involving persistent strengthening synapses that leads to a long-last increase in signal transmission between neurons.
W/ Hippocampus –>
Long-term memories
W/ Hypothalamus –>
Sympathetic Nervous Response (fight or flight)
W/ Thalamus –>
Unconscious Fear Processing
Lateral Nucleus
Inside Amygdala
- Regarded as sensory input gateway.
- Located in dorso-lateral part of the Amygdala.
Central Nucleus
Key role in emotional response to aversive stimuli –> Stress
- Damage = decrease in stress hormones, ulcers, and stress-induced illnesses.
- Stimulation = increased fear, agitation, gastric ulcers.
Basal Nucleus
Major output pathways to cerebral cortex.
- Projects to the VMPFC which leads to extinction of the conditioned fear.
- In PTSD, increased amygdala and decrease VMPFC activation.
Kluver-Bucy Syndrome
Can be cause by stroke, encephalitis, tumors, TBI and even a lobotomy.
- Damage to the bilateral amygdaloid nuclei and hippocampus.
- Results in:
Absence of fear and anger response
Psychic blindness/visual agnosia
Hyper-orality
Hyper-Sexuality w/o sexual desire
Binge eating disorder
Memory disorders
Ubach-Weithe Disease
Rare genetic disorder.
- Progressive damaging to neural tissue.
- First symptoms: weak cry/hoarse voice.
- Absence of startle or fear response.
Aggression
50-65% heritability.
- Serotonins inhibit aggressions and risky behaviors.
Testosterone’s impact on aggression
Increase in testosterone = increase in prosociability.
- Increase amygdala, hypothalamus, and PAG activation only if shown angry faces or given an unfair deal.
- Testosterone only increased aggression in those with high dominance traits.
VMPFC
The VMPFC plays a role in Impulse Control, Courage, Moral-Decision Making.
Reduced activation/volume of the VMPFC is seen in in individuals with antisocial personality disorder and impulsive/emotional murderers.
Love and the Brain
- Photos of romantic partner increase caudate nucleus (processes visual information) and increase ventral tegmental area (mediates reward system).
- Increase cortisol and adrenalin.
Post Orgasm
Women: increase oxytocin
Men: increase vasopressin
Orbitofrontal Cortex
- Involved in emotional expression.
- Gets information from frontal lobe, sensory system, and amygdala.
Affective Blindness
Those with damage to the visual cortex, can recognize facial expressions of emotions w/o conscious awareness of looking at a person’s face.
