Aggression and Stress
Effects of androgens on the aggressive behavior of mize
- Dosage of testosterone matters to a certain degree (appears to have a threshold around 30 ug/day but more testosterone dose doesn't show that great of a difference - no hormone generally leads to less aggression
Hormones that affect women's aggression
- High testosterone - low estradiol - low progesterone - high oxytocin
Effects on female rate aggression after postovarietomy (removal of ovaries)
- No distinct difference - Aggression in female mice is NOT influenced by steroid hormones from the ovaries
Adrenal medulla
- Release of epinephrine and NE - Fast but short-term response in stress - Activates sympathetic nervous system
Health psychology
- aka behavioral medicine - a field of study that focuses on psychological influences on health-related processes
Long-term stress response
- kidneys retain sodium and water - blood volume and blood pressure rise - proteins and fats converted to glucose or broken down for energy - blood glucose increases - immune system suppressed
HPA axis (hypothalamic-pituitary-adrenal axis)
- known for our response in stress - Regulate stress response - CRH ---> ACTH ---> Cortisol - Negative feedback system
Genetic risks for psychopaths
- one gene missing for those who are aggressive/psychopath as seen in one family's case study - gene isn't the only factor for psychopathy, environment is also important
Effects of anabolic steroid
- possible decrease sperm count (affect production of sperm and testosterone) - Can lead to breast development and hair loss among men - Could masculinize the body in women (facial hair growth, menstrual problems, and a deepened voice)
MBSR (mindfulness-based stress reduction) has been showed to _____ activity in the amygdala and ______ relapses of anxiety disorders or depression
- reduce - prevent
Ways to reduce stress
- relaxation training - meditation - MBSR (mindfulness0based stress reduction) therapy
Adrenal cortex
- release of glucocorticoids (cortisol) and mineralocorticoids (aldosterone) - more prolonged and slower response
The genetic components from being born from a high-licking mother can protect you from postnatal development with a mother of low-licking behavior
- shows that prenatal, postnatal, and genetic components affect experience of stress related anxiety
______ in epinephrine and NE during exam
- spike (great increase
Young people with asthma who experience stress due to peer rejection or a negative emotional climate at home have a _____ responsive adrenal system, _______ asthma symptoms, and ______ expression of anti-inflammatory genes
1. more 2. more severe 3. impaired
_____ correlation between salivary concentration of testosterone and number of fouls per game
Positive
Aggression is inhibited by
Serotonin
psychosomatic medicine
a field of study that emphasizes the role of psychological factors in disease
Ventromedial hypothalamus (VMH)
a hypothalamic region involved in sexual behaviors, eating, and aggression
Medial amygdala
a portion of the amygdala that receives olfactory and pheromonal information - important for male rats and mice to distinguish between male rivals and female mates
Aggression
behaviors that are intended to cause pain (emotional or physical)
Epigenetic regulation
changes in gene expression that are due to environmental effects rather than to changes in the nucleotide sequence of the gene - ex. maternal deprivation exerts the negative effect on adult stress responses by causing long-lasting changes in the expression of adrenal steroid receptors in the brain
Amygdala responsible for
emotion and aggression
Perception of threat (i.e. few days before an exam) shows a _______ of NE and epinephrine hormone secretion
gradual increase
Picture frustration test became more aggressive with _____ levels of salivary concentration of testosterone
higher
_____ of epinephrine when riding a train (especially when crowded)
increase
Testosterone _____ with experience and exposure
increases
Bullying as a child (occasionally and frequently) _____ risk for psychological distress, depression, anxiety disorder and suicidaliity during adulthood
increases - depression, suicide, and psychological distress greatly increase with both occasionally and frequently) - anxiety disorder risk greatly increases with frequent bullying while only increases a little with occasional bullying - Shows that small stressor overtime can leave an impact decades later
Psychopaths have _____ cortical thinning relative to non psychopaths in what areas
less left frontal cortex, bilateral temporal lobes, and cingulate cortex
DTI imaging is useful for
looking at structural differences and myelination
The _____ the serotonin levels the ____ the aggression
lower higher
Is there a cause in psychopaths
no simple causes
Damage or reduced activity in _____ can result in altered emotionality (as well as a loss of control and immaturity)
prefrontal cortex
Prefrontal cortex linked with the
regulation of correct social behavior - may control the amygdala
Biting attacks of males after castration
severely decreased (testosterone isn't produced)
Adrenal steroids ____ the immune system
suppress (why stress decreases immune response)
Castration
surgical excision of testicles or ovaries
Aggression is increased by
testosterone
Stress immunization
the concept that mild stress early in life makes an individual better able to handle stress later in life - benefits seem to be due to effective comforting after stressful events, NOT the stressful events themselves
Electrodes in the hypothalamus of a cat turned on and off activation of hypothalamus. This experiment showed that
the hypothalamus controls certain activation of aggression
Optogenetics
the use of light to excite or inhibit neurons expressing light-sensitive membrane channels, typically in transgenic mice
For ____ crimes we see an increase percentage of those who used AAS (anabolic steroid) vs those who never used AAS
violent
Hans Selye
work launched the modern field of stress research
Types of aggressive behaviors in women
1. Common - indirect (facial expression), verbal, less injurious interpersonal violence (shoving or slapping) 2. Somewhat common - alcohol related aggression 3. Less common - physical aggression - serious/injurious IPV 4. Rare - sexual aggression
Neural characteristics of aggressive women
1. EEG - greater relative left frontal asymmetry - abnormalities in the P300, N200, OR N400 components of the ERP 2. fMRI - prefrontal cortex - amygdal
Primary brain regions affected by aggression
1. Hypothalamus - specifically ventromedial hypothalamus - triggering of attacks of aggressive behavior 2. Amygdala - important for processing and detecting threats 3. Prefrontal cortex -impulse control and decision making 4. Reward - mesolimbic pathway
short term stress response
1. Increased heart rate 2. Increased blood pressure 3. Liver converts glycogen to glucose and releases glucose to blood 4. Dilation of bronchioles 5. Changes in blood flow patterns leading to decreased digestive system activity and reduced urine output 6. Increased metabolic rate
The stress response is modulated by
adrenal cortex and medulla
Intermale aggression
aggression between males of the same species - adaptive for gaining access to food and mates
Maternal aggression
aggression of a mother defending her nest or offspring - controlled by VMH and POA (preoptic area) and premammillary nucleus
Selye called the initial response to stress the
alarm reaction
Research in hamsters found that the stimulation of the corticomedial _____ increases aggression. Lesioning of this area reduced aggression
amygdala
Reduced functioning of the prefrontal cortex may lead to
an increased likelihood in aggression
Psychopath
an individual incapable of experiencing remorse
Overtime (and with experience) cortisol, epinephrine and NE ____ after/during tasks (i.e. jumping out of a plain)
decrease
First day/time jumping out of a plane, testosterone levels _____
decrease (greatly)
Amygdala location
deep within the temporal lobes
