Emotions, Stress and Aggression Flashcards
Emotion
an increase or decrease in physiological activity accompanied by feelings characteristic of the emotion
Bell’s palsy
paralysis of the facial nerve, causing muscular weakness in one side of the face.
Moebius syndrome
facial paralysis, inability to move eyes side to side
Posed expressions
can produce the intended emotion, and the associated physiological arousal
reaction when making a sad face presented with stimulus
A stimulus is more painful
When do children show most emotions?
by two years
REM sleep and newborns
During REM sleep, newborn infants who are too young even to smile at their mothers make facial expressions that correspond to happiness, fear, disgust, and surprise
Brain areas involved in emotion
Orbitofrontal cortex
Limbic system
Brainstem
Brainstem
(maybe the power) locus coeruleus • norepinephrine – emotional arousal – depression/pleasure – stress VTA, substantia nigra • dopamine • pleasure, exhilaration
Orbitofrontal cortex
(maybe the controller)
Inhibits raw emotion from amygdala
Limbic system
(the integrator) hypothalamus • ANS reactions amygdala • aggression & fear • emotional memory hippocampus • memory cingulate gyrus • pain processing • empathy
Medial forebrain bundle
tract rises from the midbrain through the hypothalamus – contains many sites for self-stimulation
Amygdala
Participates in memory formation, especially emotional ones
People with amygdala damage are unusually trusting
Anxiety-reducing drugs act on receptors in the amygdala
(in the temporal lobe, is a key structure in fear)
Klüver–Bucy syndrome
removal of temporal lobes in monkeys has a taming effect; they are socially clueless
A syndrome resulting from bilateral lesions of the amygdala
Laughter (area of activation)
activates the orbitofrontal cortex
Disgust and Guilt (area of activation)
activates the insula
Anterior cingulate cortex
combines emotional, attentional, and body information in a conscious emotional experience
Panic disorder
Temporal lobe abnormalities
Small lesions in white matter and dilation of the lateral ventricles - in 40% of patients with panic disorder
Temporal lobes are smaller in these patients
show…
increased activity of the parahippocampal gyrus
decreased activity of the anterior temporal cortex and amygdala, especially on right
Septal stimulation
produces pleasure, accompanied by sexual fantasies and arousal
Left side of the face
controlled by right hemisphere, is more expressive than the right face
Right hemisphere
identifies emotional tone
Patients with right-hemisphere damage from stroke are more likely to be unbothered or euphoric, even if their arm or leg is paralyzed
Left hemisphere
interprets meaning of the message
People with damage to the left hemisphere express more anxiety and sadness
Prefrontal (orbitofrontal) Cortex
the final destination for much of the brain’s information about emotion before action is taken
Judges behavior and its consequences
People with damage here understand moral and social rules but can’t apply the rules in their own lives
People who sustain damage early in life never learn these rules and are motivated only to avoid punishment
Abnormalities in PFC
associated with aggression, depression, and schizophrenia
Left frontal activation
emotion
Behavioral approach. Emotions regulated by this area are anger, joy
Right frontal activation
Behavioral withdrawal. Emotions regulated are fear, sadness
Right frontal lobe is more active during
negative emotion
Left frontal lobe is more active during
positive emotion
In aggressive teens, areas of brain linked with feeling reward
amygdala and striatum
become active when they observe pain inflicted on others
Stress
a demanding condition in the environment and it is the individuals’ internal response to that situation
Stress response activates…
the sympathetic nervous system, largely under hypothalamic control
Stress results in…
increases in heart rate, blood flow, and respiration rate help the person deal with the situation
Adrenal cortex secretes…
steroid hormones
Adrenal medulla releases…
epinephrine
norepinephrine
Cortisol
a stress hormone that increases blood glucose and breaks down protein
can damage areas of the brain (extreme cases)
Autonomic Activation during a Stress Situation
Strength, courage, confidence are gained each time a fear is faced (skydiving)
Hormonal Changes in Response to Social Stress
Norepinephrine
epinephrine
Acute Stress
Hypothalamus activates the pituitary
Immune system is boosted
Stress hormones stimulate astrocytes to release fibroblast growth factor 2, which in turn leads to new neurons
Acute stress causes hypothalamus to activate the pituitary, which stimulates adrenals to release…
epinephrine and norepinephrine, which increase output from the heart and liberate glucose
cortisol, which provides sustained release of energy to cope
Chronic stress
interferes with memory, appetite, sexual desire and performance;
depletes energy and disrupts mood;
compromises the immune system
Six years after Three Mile Island nuclear accident, residents showed impaired concentration and immune response
Hormones released during chronic stress do what to the immune system?
Suppress the immune system
Post-traumatic Stress Disorder
PTSD develops in response to a stressful event of exceptionally threatening or catastrophic nature: assault, car wrecks, rape
Symptoms of PTSD
re-experiencing (e.g., flashbacks, nightmares) avoiding people or situations associated with event hyperarousal symptoms (panic)
Treatment of PTSD
behavioral desensitization
propranolol
natural course of PTSD
Usual onset of symptoms a few days after the event
Many recover without treatment within months/years of event
Treatment means that about 20% more people with PTSD recover
Generally 33% remain symptomatic for 3 years or longer with greater risk of secondary problems
Frontal cortex and hippocampal volume associated with PTSD
reduced in combat veterans with PTSD and in victims of childhood abuse
NE levels are _____ in introverts
higher
NE blocks immune system
Aggression
behavior that is intended to harm
Reactive aggression
is impulsive, provoked, and emotional
Proactive aggression
is premeditated, unprovoked, emotionless
Tumors in _____, _____, or _____ can cause aggression
amygdala, hypothalamus or septal area
Seizure activity in the _____ increases aggression
amygdala
Murderers have higher activity of the _____ and _____
amygdala and hypothalamus
Removing the amygdala reduced aggression in __-__% of patients
33-100%
Murderers (reactive aggressors) have lower activity in the ____
prefrontal cortex
Less gray matter in the prefrontal cortex is associated with _____
antisocial personality disorder
Proactive aggression is associated with _____
psychopathy
Proactive agressors have
less autonomic response to stress
impaired amygdala function
50% of aggression is attributed to _____
genetics
_____ during childhood increases risk of adult aggression
Neglect/deprivation
Dyscontrol syndrome
caused by temporal lobe disorders, underlie some violence (road rage)
Sociopaths are incapable of _____
remorse
charles manson, ted bundy
Long term stress may damage the _____.
hippocampus
