Download Emotional Behaviors

Chapter Twelve
Emotional Behaviors
Usefulness of Emotions
Assist in decision making
Prefrontal cortex damage lose their emotions and their decision
making suffers
Emotions and readiness
Emotions start the fight-or-flight response
Figure 12.1 The limbic system
The limbic system is a group of structures in the interior of the brain. Here you see
them as if you could look through a transparent exterior of the brain.
Theories of Emotions
Theories of emotional arousal
James-Lange theory-autonomic arousal and skeletal actions
occur; what we label that arousal is the emotion
Cannon-Bard theory-a stimulus evokes the emotional
experience and the physical arousal simultaneously but
independently
Schacter-Singer theory-the physiological changes would tell
you how strong your emotion is, but you would need some
contextual or cognitive cue to identify which emotion you are
feeling
Video
Stress and Health
Stress-the nonspecific response of the body to any demand made upon it
Stress Activates the Autonomic Nervous system
Figure 12.4 The sympathetic and parasympathetic nervous systems
Review pages 91–93 for more information.
Evidence of Mind-Body Interactions
Psychosomatic Illness
Onset of illness due to someone’s personality, emotions, or
experiences
Ulcers
Ulcers are formed when an individual experiences a great deal
of stress
Control of the stress can alter ulcer formation
Ulcers are formed when the parasympathetic nervous system
rebounds after the stress
Evidence of Mind-Body Interactions
Heart Disease
Data may indicate that people who experience frequent hostility
are more prone to heart disease
Voodoo Death
Richter found that voodoo death may be due to
parasympathetic rebound
Stress Activation in the Body
HPA Axis (hypothalamic-pituitary-adrenal) Autonomic Nervous System
Rapid Response System
Slower to respond
Important in more Acute
Important in chronic stress
Stressors
Activation of hypothalamus causes
Results in activation of
release of ACTH from pituitary and
Sympathetic Nervous
release of cortisol from adrenal
System
Cortisol mobilizes resources but can be
harmful if prolonged exposure
Figure 12.5 The hypothalamus-anterior pituitary-adrenal cortex axis
Prolonged stress leads to the secretion of the adrenal hormone cortisol, which
elevates blood sugar and increases metabolism. These changes help the body
sustain prolonged activity but at the expense of decreased immune system activity.
Immune System Cells
Consists of cells that protect the body against invaders like bacteria and
viruses
Leukocytes
White Blood Cells
Patrol blood and other body fluids for invaders
Identifies antigens on intruders and signal attack from immune
system
Macrophage
Surrounds intruder, digests it, and exposes its antigens on its
own surface
More Immune System Cells
B Cell
attaches to an intruder and produces specific antibodies
to attack the intruder’s antigen
antibodies are Y-shaped proteins that circulate in the
blood, specifically attaching to one kind of antigen
T Cell
Cytotoxic-directly attack intruder cells
Helper-stimulate other T cells or B cells to multiply more
rapidly
Natural Killer Cells
blood cells that attach to certain kinds of tumor cells and
cells infected with viruses
More Immune System Cells/Products
Cytokines
Chemicals released by the immune system that attack
infections and also communicate with the brain to elicit antiillness behaviors
Fevers make the body a lest hospitable host
sleepiness, decreased muscle activity, decreased sex drive
conserve energy
decreased appetite may deprive body of iron needed by
viruses
Figure 12.6 Immune system responses to a bacterial infection
A macrophage cell engulfs a bacterial cell and displays one of the bacteria’s
antigens on its surface. Meanwhile a B cell also binds to the bacteria and
produces antibodies against the bacteria. A helper T cell attaches to both the
macrophage and the B cell; it stimulates the B cell to generate copies of itself,
called B memory cells, which immunize the body against future invasions by
the same kind of bacteria.
Stress Effects on the Immune System
Short-term stress acts to increase immune system function
Long-term stress decreases immune system function
Reduced levels of natural killer cells, B cells, and T cells
Reduced T cell function
Reduced NK cell function
Reduced resistance to infection
Stress Effects on the Brain
Selective cell death to hippocampal cells
Due to high cortisol levels
damage to hippocampus can lead to an increase in cortisol
levels; creating a vicious cycle of cell death and high cortisol
levels
Aged people with high cortisol levels show the greatest
deterioration of the hippocampus and resulting memory
impairment
Post-Traumatic Stress Disorder
Who is Affected?
People who have had a traumatic experience of being severely
injured or threatened
people who have seen other people harmed or killed
What are the Symptoms?
Frequent flashbacks and nightmares about the event
avoidance of reminders of the event
exaggerated arousal in response to noises and other stimuli
Attack Behaviors
Affective Attack
highly emotional attack behavior
triggered by pain or threat or when primed
Heredity and Environment in Human Violence
Evidence for a genetic or prenatal environment component
Children exposed to families experiencing discord, depression,
substance abuse or legal problems are more likely to demonstrate
aggressive behaviors
Physiology of Aggression
Hormones
High levels of testosterone are associated with aggression
Serotonin
low serotonin turnover is associated with increased aggression
Temporal Lobe
Stimulation of ventromedial hypothalamus or amygdala can
result in aggression
Figure 12.7 Location of amygdala in the human brain
The amygdala, located in the interior of the temporal lobe, receives input
from many cortical and subcortical areas. Part (a) shows a blow-up of
separate nuclei of the amygdala.
Escape Behaviors
Two Types
Fear-transient
Anxiety-can be long lasting
Brain Mechanisms
Associated with excitation of amygdala
Most likely associated with GABA pathways
Anti-anxiety drugs decrease fear and anxiety by facilitating
inhibition at GABA synapses
Figure 12.14 The GABAA receptor complex
Of its four receptor sites sensitive to GABA, the three a sites are also
sensitive to benzodiazepines.