Chapter 12Emotional Behaviors

Module 11.1:

What Is Emotion?

Module 11.3:

Module 11.2:

Attack and Escape Behaviors

Stress and Health

What is Emotion?• An emotional state

has three aspects:

1. Cognition (assessment of situation: “This is dangerous.”)

2. Feelings (“I feel scared”—requires labeling)

3. Action (involves physical response, such as running away)

Common Sense View

What is Emotion?• Action, or “readiness for action” is a product of the

autonomic nervous system (ANS).• James-Lange theory (1884): autonomic arousal and

skeletal action occur first, then come feelings/emotions.• The emotion that is felt is the label that we give the arousal

of the organs and muscles.

What is Emotion?

• According to the James-Lange theory:

1. People with a weak autonomic or skeletal response should feel less emotion.

2. Increasing one’s response should enhance an emotion.

What is Emotion?: Evidence Supporting the James-Lange Theory

• Botulinum toxin (BOTOX): blocks transmission at synapses and nerve-muscle junctions, resulting in temporary paralysis, resulting in weaker than usual emotional responses

• People with “pure autonomic failure” report feeling emotion less intensely.– Pure autonomic failure - output

from the autonomic nervous system almost entirely fails.

What is Emotion?: Evidence Supporting the James-Lange Theory

• Creating certain body actions may also slightly influence emotion.– smiling slightly increases

happiness.– Inducing a frown leads to the

rating of stimuli as slightly less pleasant.

• Indicates that perception of the body's actions do contribute to emotional feeling

What is Emotion?: Evidence Refuting the James-Lange Theory

Research indicates that paralyzed people report feeling emotion to the same degree as prior to their injury

• Contradictory research suggests other factors are involved in the perception of emotion.

What is Emotion?: Basic Emotions

• Facial expressions are just one source of information about emotion

• Research indicates that facial expressions, body posture, tone of voice all convey emotional meaning

What is Emotion?

• Emotional experiences arouse many areas of the brain.• The limbic system has traditionally been regarded as

critical for emotion.• PET and fMRI studies also suggest many other areas of

the cerebral cortex, especially the frontal and temporal lobes, are activated during an emotional experience.

What is Emotion?

• Emotions tend not to be localized in specific parts of the cortex.

• A single emotion increases activity in various parts of the brain.

What is Emotion?

• Inactivation of the medial frontal cortex appears to impair the ability to recognize angry expression.

What is Emotion?• Insular cortex

– strongly activated when experiencing disgust

– primary taste cortex– reacts to frightening

stimuli as well.

What is Emotion?

• Behavioral Inhibition System (BIS): associated with increased activity of the frontal and temporal lobes of the right hemisphere– Increases attention and

arousal– Inhibits action– Stimulates emotions

such as fear and disgust

• The two hemispheres of the brain play different roles in emotion.

What is Emotion?

• Behavioral Activation System: increased activity of left hemisphere frontal and temporal areas – associated with

“approach” – marked by low to

moderate arousal– registers happiness

or anger

What is Emotion?

• Differences in prefrontal cortex activity relates to personality.

• People with greater activity in the left hemisphere tend to be happier, more out-going and friendlier.

• People with greater right hemisphere activity tend to be socially withdrawn, less satisfied with life, and prone to unpleasant emotions.

What is Emotion?

• The right hemisphere seems to be more responsive to emotional stimuli than the left.

• Damage to the right temporal cortex causes problems in the ability to identify emotions of others.

What is Emotion?• One major function of emotion is to help us make decisions.• Failure to anticipate the unpleasantness of an event can

lead to bad decision making.• Low autonomic arousal is correlated with making logical

moral decisions

Attack and Escape Behaviors• Pain, threat or other

unpleasant stimuli usually trigger an attack behavior.

• Attack behaviors are associated with increased activity in the corticomedial area of the amygdala.

• After experiencing a provocation, people are more likely to attack for a period of time afterwards.

• An initial attack behavior increases the probability of a second attack behavior.

Attack and Escape Behaviors

• Twins studies suggest genetic contribution to the likelihood of violent behavior.

• Smoking cigarettes while pregnant is correlated with violent behavior in offspring.

• The effect is particularly strong if the mother smoked and also had complications during pregnancy.

Attack and Escape Behaviors• Environmental factors can

combine with genetic factors to influence behavior.

• Adopted children have the highest probability of violent behavior if the biological parent has a criminal record and there is discord in the adopted family household.

• A biological predisposition alone, or a troubled adoptive family by itself, produces only moderate effects.

Attack and Escape Behaviors• On average, males engage in more aggressive and violent

behaviors than do females.• Male aggressive behavior is influenced by the hormone

testosterone.• Research shows that men with the highest rates of violent

behavior also have slightly higher testosterone levels.

Attack and Escape Behaviors

• Studies suggest a connection between aggressive behavior and low serotonin release.

• Turnover is the amount of release and resynthesis of a neurotransmitter by presynaptic neurons.

• In human and animal studies, low serotonin turnover has been linked to: – violent behavior and violent

crime– suicide by violent means

Attack and Escape Behaviors

• “Fear” is associated with a strong tendency to escape from an immediate threat.

• “Anxiety” is a general sense that something dangerous might occur.– Not necessarily

associated with the desire to flee.

Attack and Escape Behaviors

• The startle reflex is the extremely fast response to unexpected loud noises.– found in young

infants and thus unlearned.

• Auditory information stimulates an area of the pons that commands the tensing of the neck and other muscles.

Attack and Escape Behaviors

• Stimuli previously associated with the startle response enhances the startle response.– Cells in the amygdala are

responsible.• Cells in the amygdala receive

information from pain, vision, and hearing circuits.

• Axons extend to areas in the midbrain that relay information to the nucleus in the pons.– The relay enhances the

startle reflex.

Attack and Escape Behaviors

• Output from the amygdala to the hypothalamus controls autonomic fear responses.

• Axons extending from the amygdala to the prefrontal cortex regulate approach and avoidance responses.

Attack and Escape Behaviors

• fMRI studies of humans suggest the amygdala responds strongly to emotional stimuli and facial expressions.– Activity is strongest when

the meaning is unclear and requires some processing.

– With some exceptions, looking at happy faces activates the amygdala only weakly.

• Amygdala also responds to stimuli not consciously perceived.

Attack and Escape Behaviors

Damage to the amygdala interferes with:•learning of fear responses•retention of fear responses previously learned•interpreting or understanding stimuli with emotional consequences

Attack and Escape Behaviors: Anxiety Disorders

• Damage to the amygdala impairs the processing of emotional information when the signals are subtle or complicated.

• Amygdala damage affects the ability to judge “trustworthiness” in people.

• People with amygdala damage focus on emotional stimuli the same as irrelevant stimuli or details.

Attack and Escape Behaviors• People with overactive amygdalae may experience anxiety:

– physical distress, including muscle tension, heart palpitations, sweating, rapid breathing

– emotional distress, including worry, etc.• Panic Disorder: episodes of extreme anxiety• Generalized Anxiety Disorder: recurrent/continuous anxiety

with no identifiable cause• Phobias: fear of a specific place, thing, or situation• Post-traumatic Stress Disorder (PTSD): anxiety that occurs

after experiencing a traumatic event

Attack and Escape Behaviors• Excessive fear and anxiety disorders

are associated with hyperactivity in the amygdala

• Drugs intended to control anxiety alter activity at amygdala synapses.

• The main excitatory neuromodulator in the amygdala is CCK, and the main inhibitory transmitter is GABA.– Injections of CCK-stimulating drugs

into the amygdala enhance the startle response.

– Drugs that increase GABA activity decrease panic.

GABA =STOP

CCK/Orexin=GO

Attack and Escape Behaviors

• Benzodiazepines are the most commonly used anti-anxiety drugs (anxiolytics or tranquilizers).

• Benzodiazepines bind to the GABAA receptor complex, and facilitate the effects of GABA.

• Benzodiazepines exert their effects in the amygdala, hypothalamus, midbrain, and other areas.

Attack and Escape Behaviors

• Ethyl alcohol has behavioral effects similar to benzodiazepines.

• Alcohol enhances GABA effects.

Stress and Health

• Behavioral medicine emphasizes the effects of diet, smoking, exercise, stressful experiences, and other behaviors on health.

• Emotions and other experiences influence illness and pattern of recovery.

Stress and Health

• Hans Selye (1979) defined stress as the non-specific response of the body to any demand made upon it.

• Threats on the body activate a general response to stress called the general adaptation syndrome.

Stress and Health

The General Adaptation Syndrome:• Alarm stage - characterized by

increased sympathetic nervous system activity.

• Resistance stage - sympathetic response declines, the adrenal cortex releases cortisol and other hormones that enable the body to maintain prolonged alertness.

• Exhaustion stage - occurs after prolonged stress and is characterized by inactivity and decreased immune system.

Stress and HealthStress activates two systems in the body:

1. The autonomic nervous system - “fight or flight” response that prepares the body for brief emergency responses

2. The HPA axis - the hypothalamus, pituitary gland, and adrenal cortex.

Stress and Health• The HPA axis becomes the

dominant response to prolonged stressors.

• Activation of the hypothalamus induces the pituitary gland to secrete adrenocorticotropic hormone (ACTH).

• ACTH stimulates the adrenal cortex to secrete cortisol.

• Cortisol enhances metabolic activity and elevates blood levels of sugars and other nutrients to mobilize energies.

Stress and Health

• Prolonged increased cortisol levels impair the immune system.

• The immune system consists of cells that protect the body against viruses and bacteria. – Leukocytes – white blood cells.

Stress and Health

• During an infection, leukocytes and other cells produce small proteins called cytokines.– Combat infection and

communicate with the brain to inform of illness.

• Cytokines in the brain produce symptoms of illness.– Fever, sleepiness, lack of

energy etc.– Sleep and inactivity are the

bodies way of conserving energy to fight illness.

Stress and Health

• Psychoneuroimmunology is the study of the relationship between the nervous system and the immune system.

• Deals with the way in which experiences, especially stressful ones, alter the immune system.

• Also deals with how the immune system influences the central nervous system.

Stress and HealthProlonged stress response is damaging to the body:•Increase of cortisol detracts from the synthesis of proteins of the immune system. •Cortisol enhances metabolic activity in the body.•Significantly increases the likelihood of illness, including autoimmune disease (immune system attacks normal cells)

Stress and Health• Prolonged stress response is

damaging to the body:– Can be harmful to

hippocampus and can affect memory.

– When metabolic activity is high in the hippocampus, the neurons are more sensitive to damage by toxins or over-stimulation.

– Stress also impairs the adaptability and the production of new hippocampal neurons.

Stress and Health• Posttraumatic stress disorder (PTSD) occurs in some people

after terrifying experiences and includes the following symptoms:– Frequent distressing recollections– Nightmares– Avoidance of reminders of the event– Exaggerated arousal in response to noises and other stimuli

Stress and Health• Studies have revealed

most PTSD victims have a smaller than average hippocampus.

• PTSD victims show lower than normal cortisol levels after the trauma.– People with low

cortisol levels may be ill-equipped to combat stress and more prone to the damaging effects of stress.

Stress and Health• There are many ways to combat and manage stress!