PSY290 - Emotion and Psychiatric Disorders

emotion

a brief conscious experience associated with intense mental activity and a high degree of pleasure/displeasure

how do physiological states associated with emotion occur?

with activation of the autonomic nervous system

what is the benefit of having emotions?

they are adaptive, facilitate decision making in cases where time is short and information is lacking/limited options available

emotional regulation

the ability to control emotions

• related to mental health and job performance

physiology of emotions

the autonomic nervous system causes responses like changes in organ function and these effects are rapid and involuntary

what are the 6 core emotions?

angry, afraid, surprised, happy, sad and disgusted

what system is associated with facial expressions?

the basal ganglia

how is the basal ganglia impaired?

by parkinson’s disease

how are emotions innate?

• the facial and physical expressions accompanying them are consistent across all cultures and don’t require experience

what muscles are involved in the real smile

the orbicularis oculi for the eyes and zygomaticus major for the moth

which muscle is very difficult to contract voluntarily?

orbicularis oculi

what physiological responses are related to lying?

inappropriate smiling, nervous laughter, stiff upper body, verbal stumbling, lack of details so cant tell story backward in time and physiological changes

why is the polygraph not viewed fondly by the legal community?

many people show physiological changes just cause they are aroused due to nervousness not necessarily cause they’re lying

James Lange Theory

there is a sequence of events that leads to emotions first starting with perception of the stimulus triggering the physiological reactions that leads to the emotional manifestations interpreting the physiological reactions

what are the issues associated with the James-Lange Theory?

emotional states are not easily separable from physiological characteristics so we can’t use them alone to explain emotional states

Cannon-Bard Theory

separate pathways where we get emotional states so we can get one without the other

• the physiology of most emotions is similar

what are the issues associated with the Cannon-Bard theory?

disruption of one affects the other

• emotion will be affected if the ability to create physiological states is lost (usually positive ones are reduced)

modern view of emotion

product of a complex, reciprocal influences of the brain, nervous system and perception on each other

what parts are the brain are vital in emotion

the limbic system, hippocampus, cingulate cortex

what parts of the limbic system are emotion generators?

the hypothalamus and the amygdala

what part of the brain regulates/inhibits emotion?

the frontal lobe

Phineas Gage

found that injury to the frontal cortex is associated with pronounced changes in behavior like impulsivity, inappropriate social behavior and irritability suggesting that the frontal cortex plays a role in inhibiting emotion

Sham rage

cats where the cortex was hostile to all stimuli and found to be absent in animals with hypothalamic damage suggesting its role in creating emotion

Kluver-Bucy Syndrome

hyperorality, hypersexuality, repeated investigation of familiar object and no fear

what causes Kluver-Bucy Syndrome

damage to the anterior temporal lobe and removal of the amygdala

Patient SM

amygdala was damages causing difficulty expressing fear and recognizing fear in other, leading to the processing of facial expressions in others to be different and inappropriate social distancing

what contributes to fear?

the amygdala, hippocampus and prefrontal cortex

unlearned fear in humans

argument that these fear include heights, loud noises, approaching objects, snakes and spiders

• very few

what is the hippocampus necessary for?

contextual fear conditioning

what is the role of the prefrontal cortex in emotion?

it is connected the amygdala and can inhibit it

• vital for regulation of emotions

• connectivity modified by experience

what causes emotional dysregulation?

the loss of the prefrontal cortex

extinction

gradual reduction in a conditioned response to a conditioned stimulus following repeated presentations of the conditioned stimulus alone

what is critical for establishing extinction in humans?

the ventromedial prefrontal cortex

reinstatement

one conditioned stimulus-unconditioned stimulus repairing brings back the full conditioned response

spontaneous recovery

time dependent recovery of conditioned response to conditioned stimulus

renewal

extinguish conditioned response to conditioned stimulus in one context still have conditioner response to conditioned stimulus in other contexts

stress

feeling of tension resulting from the perception of demanding circumstances

what makes a stressor

Novelty

Unpredictability

Threat to the ego

Sense of control

novelty

something new you have not experienced before

unpredictability

something you had no way of predicting

threat to the ego

your competence as a person is called into question

sense of control

you feel you have little or no control over a situation

major stressors

work, money and the economy

stress scales

• social readjustment rating scale

• daily hassle scale

• perceived stress scale

what psychological disorder is strongly related to frequency of stressors?

depression

chronic stress

associated with changes in emotion and risk for mental disordered and part of the negative effects are due to changes in the brain

how does chronic stress affect neurons?

neurons show less branching (animals)

glucocorticoid receptors

cortisol binds to it and GR cells prevent further cortisol release terminating the stress response

• less GR expression = more anxiety

PTSD symptoms of stress

cortical thinning occurs depending on the severity of stress and has the greatest effect on the frontal cortex and temporal lobe

how is the hippocampus affected under stress?

smaller in size

Stress models

• social defeat

• chronic intermittent stress model

social defeat model

analogous to bullying and there’s asssociation with cortisol, lower testosterone, smaller testes and shorter lifespans

depression

• anhedonia

• fatigue

• low self worth/guilt

• disturbed sleep, appetite and activity

• inability to concentrate

• suicidal thoughts

Types of depression

• unipolar depressive disorder

• bipolar disorder

• post-partum depression

• dysthymia

• seasonal affective disorder

what is lower in volume in depression?

hippocampus, OFC and anterior cingulate cortex

what is higher in activity in depression?

the OFC and amygdala

what compounds are lower in concentration for depression?

5HT/serotonin, noradrenaline and GABA

what compounds are higher in concentration for depression?

cytokines and cortisol

Depression theories

• monoamine hypothesis

• neurogenesis hypothesis

• neuroendocrine hypothesis

• neuroinflammation hypothesis

• GABA/Glutamate hypothesis

monoamine hypothesis

there are lower levels of monoamine metabolites in depression, depletion of 5HT and tryptophan produces depressive like behavior

drugs for depression

they work by modifying monoamine transmission

• SSRIs

• MAOis

• TCAs

jitteriness syndrome

antidepressants can sometimes increase anxiety

alternative SSRIs mechanisms

depression is not related to monoamine levels but a secondary process triggered by monoamines

• SSRIs might facilitate adult neurogenesis and improve mood by inducing monoamine-dependent remodeling of the brain

depression treatment

psychotherapy, cognitive behavioral therapy and drugs

• Transcranial magnetic stimulation

• ketamine

• meditation

• electroconvulsive therapy

• cingulotomy

anxiety

related to activity in the amygdala and damage to it heavily affects anxiety

• inhibition of it reduces anxiety

bipolar disorder

episodes of depression and elevated mood where the individual feels extremely energetic, happy, and irritable having no need for sleep and making poor decisions regardless of the consequences

creativity

people with bipolar are more likely to be in creative professions and the genes involved in creativity may be linked to mental health regulating genes

BPD treatments

lithium, valproate, anticonvulsants and antipsychotics

schizophrenia

• positive, negative and cognitive symptoms

• prefrontal cortex and hippocampus affected

• abnormal dopamine signaling (high mesolimbic and low mesocortical)

• treatment with DH2 receptor antagonists (conventional) or 5HT2 receptors (atypical

personality disorders

inflexible patterns of behavior that lead to distress in most cases emerging in adolescence and difficult to diagnose

types of personality disorders

borderline personality disorder, narcissistic personality disorder, antisocial personality disorder

psychopathic personality

guiltless, manipulative, charming, callous and self-centered with awareness of problematic behavior and lack of empathy and self control

psychopathic personality risk factors

form of NDD where early trauma, exposure to violence and brain damage in the OFC as well as poor parental relationship

brain changes in ASPD

reduced function , volume and connectivity in the frontal cortex and amygdala

low arousal theory in ASPD

inappropriate autonomic nervous system reactivity, chronic state of stimulus hunger, lower resting heart rate, and electrodermal activity, abnormal response to threatening stimuli affecting ability to learn from punishment