Module 12 What Causes Emotional and Motivated Behavior? Flashcards

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1
Q

Emotion

A

-Cognitive interpretation of subjective experience that can influence thought and behavior

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2
Q

Androgen

A

-hormones related to masculine characteristics and that play a role in levels of sexual interest

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3
Q

Innate releasing Mechanism (IRM)

A

-Hypothetical mechanism that detects specific sensory stimuli and directs an organism to take a particular action

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4
Q

Evolution Psychology

A

-Discipline that seek to apply principles of natural selection to understand the causes of human behavior

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5
Q

Reinforcer

A

-In operant conditioning, any event that strengthens that behavior it follows

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6
Q

Learned Taste aversion

A

-Acquired association between a specific taste or odor and illness; leads to an aversion to food that have the taste or odor

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7
Q

Preparedness

A

-Predisposition to respond to certain stimuli differently from other stimuli

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8
Q

Orbitofrontal Cortex (OFC (Orbital frontal cortex))

A

-Prefrontal cortex behind the eye socket (the orbits); receives projections from the dorsomedial nucleus of the thalamus; central to a variety of emotional and social behaviors, including eating

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9
Q

Pheromone

A

-Odorant biochemical released by one animal that acts as a chemosignal and can affect the physiology or behavior of another animal

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10
Q

Regulatory Behavior

A

-Behavior motivated to meet an animal’s sutvival needs

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11
Q

Homeostatic Machanism

A

-Process that maintains critical body functions within a narrow, fixed range

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12
Q

Nonregulatory Behavior

A

-Behavior unnecessary to animal’s basic survival needs

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13
Q

Pitutary Glands

A

-Endocrine gland attached to the bottom of the hypothalamus; its secretions control that activities of many other endocrine glands; associated with biological rhythms

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14
Q

Medial Forebrain Bundle (MFB)

A

-Tract that connects brainstem structures with various parts of the limbic system forms the activating projections that run from the brainstem to the basal ganglia and frontal cortex

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15
Q

Releasing Hormone

A

-Peptide released by the hypothalamus that increases or decreases hormone release from the anterior pituitary

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16
Q

Anorexia Nervosa

A

-Exaggerated concern with being over weight that leads to inadequate food intake and often exercising; can lead to severe weight loss and even starvation

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17
Q

Aphagia

A

-Failure to eat; may be due to an unwillingness to eat of to motor difficulties, especially with swallowing

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18
Q

Hyperphagia

A

-Overeating that leads to significant weight gain

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19
Q

Osmotic Thirst

A

-Thirst that results from a high concentration of dissolved chemicals, or solutes in body fluids

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20
Q

Hypovolemic Thirst

A

-Thirst produced by a loss overall fluid volume from the body

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21
Q

Activating Effects

A

-Hormonal actions that influence in the adult brain

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22
Q

Organizing Effects

A

-Hormonal actions that influence the organizational development of the fetal brain

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23
Q

Sexual Dimorphism

A

-Differential development of brain areas in the two sexes

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24
Q

Sexual Orientation

A

-A person’s pattern of sexual attraction-to the opposite sex or to the same sex or to both sexes

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25
Q

Gender Identity

A

-The degree to which a person feels male or female

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26
Q

Transgender

A

-Possessing personal characteristics that transcend traditional gender boundaries and corresponding sexual norms; a person’s belief that he or she was born the worng sex

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27
Q

Hippocampus

A

-Distinctive allocortices structure lying in the medial temporal lobe; participates in species-typical behaviors, memory, and spatial navigation and is vulnerable to the effects of stress

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28
Q

Amygdala (Greek word for Almond)

A

-The part of the brain that participates in species-typical behaviors, emotion, and emotional memory, reflecting the general shape in the medical temporal lobe

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29
Q

Kluver-Bucy Syndrome

A

-Behavioral syndrome, characterized especially by hypersexuality, that result from bilateral injury to the temporal lobe

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30
Q

Psychosurgery

A

-Any neurosurgical technique intended to alter behavior

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31
Q

Generalized Anxiety Disorder

A

-Persistently high levels of anxiety often accompanied by maladaptive behavior to reduce anxiety; thought to be caused by chronic stress

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32
Q

Phobia

A

-Fear of a clearly defined object or situation

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33
Q

Panic Disorder

A

-Recurrent attacks of intense terror that come on without warning and without any apparent relationship to external circumstances

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34
Q

What Causes Emotional and Motivated Behavior?

A
  • Identifying the Causes of Behavior
  • Chemical Senses
  • Evolution, Environment and Behavior
  • Neuroanatomy of Motivated and Emotional Behavior
  • Control of Regulatory and Nonregulatory Behavior
  • Reward
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35
Q

Identifying the Causes of Behavior

A
-Emotion
~Cognitive interpretation of subjective feelings
-Motivation
~Behavior that seems purposeful and goal- directed
-Neuroanatomy of Emotion and Motivation
~Hypothalamus
~Limbic System
~Frontal Lobe
36
Q

Behavior for Brain Maintenance

A

-Sensory Deprivation
~Experimental setup in which a subject is allowed only restricted sensory input; subjects generally have a low tolerance for deprivation and may even display hallucinations
~Hebb and Heron (1950s)
*After about 4 to 8 hours, subjects became quite distressed; few subjects lasted more than 24 hours
*Brain has an inherent need for stimulation; one reason that we engage in behavior is to stimulate the brain

37
Q

Neural Circuits and Behavior

A

-Researchers have identified brain circuits for reward and discovered that these circuits can be modulated to increase or decrease activity
~Hormones
~Chemical senses (smell and taste)
-The main reason why a particular thought, feeling, or action occurs lies in what is going on in brain circuits
-Researchers have not been able to link drives and brain activity
-What researchers have found, however, is that behavioral change correlates with changes in hormones and cellular activity
~Example: A man’s frequency of copulation is correlated with his levels of male hormones, called androgens (male hormones related to level of sexual interest)

38
Q

Chemical Senses

A

-Chemosignals (chemical signals) play a central role in motivated and emotional behavior
~Identify group members
~Mark territories
~Identify favorite and forbidden foods
~Form associations among odors, tastes, and emotional events
-Odor and taste play a fundamental role in the biology of emotional and motivated behavior

39
Q

Olfaction

A

-We can discriminate thousands of odors, yet we have great difficulty finding words to describe what we smell
-Designed to discriminate whether information is safe or familiar
~Is the smell from an edible food?
~From a friend or from a stranger?

40
Q

Receptors for Smell

A
  • Chemicals in the air we breathe dissolve in mucosa to interact with cilia
  • Metabotropic activation of a specific G protein leads to an opening of sodium channels and a change in membrane potential
41
Q

Olfactory Pathways

A

-Olfactory receptor cells project to the olfactory bulb
-Many olfactory targets (amygdala and pyriform cortex) have no connection through the thalamus
-Thalamic connection does project to the orbitofrontal cortex (OFC)
~Emotional, social, and eating behaviors

42
Q

Accessory Olfactory System

A
  • Pheromones: biochemicals released by one animal that act as chemosignals and can affect the physiology or behavior of another animal
  • Detected by a special olfactory receptor system known as the vomeronasal organ (connected to the amygdala and hypothalamus)
43
Q

Human Olfactory Processing

A

-Humans have a surprisingly acute sensitivity to smells that are behaviorally relevant
~Can identify their own odor, the odor of kin versus non-kin, and the odor of friends versus strangers with accuracy well above chance
*Body odors activate brain regions involved in emotional processing
-Processing body odors is mostly unconscious and represents an automatic process

44
Q

Gustation

A

-Within the human species, clear differences in taste thresholds and preferences are obvious
~Supertasters versus nontasters
-Children are much more responsive than adults to taste
~By age 20, humans have lost at least an estimated 50 percent of their taste receptors

45
Q

Receptors for Taste

A

-Each of the five different taste-receptor types responds to a different chemical component of food
~Sweet, sour, salty, and bitter.
-Fifth is called the umami receptor
~Especially sensitive to glutamate

46
Q

Gustatory Pathways

A

-Cranial nerves 7, 9, and 10 form the main gustatory nerve, the solitary tract.
~Gustatory region in the insula is dedicated to taste
~Primary somatosensory region is responsive to tactile information (localizing tastes and textures on tongue)
-Gustatory to orbital cortex: mixture of olfactory and gustatory input gives rise to our perception of flavor
-Areas in the right orbital cortex mediate the pleasantness of tastes, whereas the same region in the left hemisphere mediates the unpleasantness of tastes
-Gustatory projections to amygdala play a role in pleasantness and salience of food

47
Q

Evolution, Environment, and Behavior

A

-Investigating the evolutionary and environmental influences on brain-circuit activity that contribute to behavior.
~Why does the sight or smell of a bird or a mouse trigger stalking and killing in a cat?
~Why does the human body stimulate sexual interest?

48
Q

Evolutionary Influences on Behavior

-Innate Releasing Mechanism (IRM)

A
  • Hypothetical mechanism that detects specific sensory stimuli and directs an organism to take a particular action
  • The brain must have a set of norms against which it can match stimuli so as to trigger an appropriate response
  • Although IRMs are prewired into the brain, they can be modified with experience
49
Q

Innate Releasing Mechanisms

A
  • “Halloween” cat innately stimulates cats to respond defensively –raised fur, arched backs, and bared teeth
  • The “Picasso” cat evokes no response at all
50
Q

Innate Releasing Mechanisms in Humans

A
  • Adult displays various exaggerated facial expressions
  • Babies responded with very much the same expressions
  • Newborns were too young to be imitating the adult faces intentionally
  • Babies innately match these facial expressions to internal templates
51
Q

Evolutionary Influences on Behavior

A

-Evolutionary Psychology
~Discipline that seeks to apply principles of natural selection to understand the causes of human behavior
~Behaviors exist because the neural circuits producing them have been favored through natural selection
-B. F. Skinner (1904–1990)
~Suggested a strong role of learning in behavior
~Reinforcer
*In operant conditioning, any event that strengthens the behavior that it follows
~Experience shapes behavior by pairing stimuli and reinforcers
-Many complex behaviors are learned, and learning takes place in a brain that has been selected for evolutionary adaptations
-Learned Taste Aversion
~Acquired association between a specific taste or odor and illness
~Leads to an aversion to foods having that taste or odor
*Example: Garcia (1966)
**Coyotes were killing sheep
**Poisoned a sheep carcass, made coyotes ill
**Most coyotes learned never to eat sheep again
-Preparedness
~Predisposition to respond to certain stimuli differently than to other stimuli
~Brain is prewired to make certain types of associations but not others

52
Q

Inferring Purpose in Behavior: To Know a Fly

A

-When studying the causes of behavior, one must be careful not to infer purpose from an organism’s actions
~Do not assume that behavior is intentional
~Example
*Although a fly may look as if it is behaving with “purpose in mind,” its behaviors are controlled by a series of very simple mechanisms that are not even remotely related to our concept of thought

53
Q

Neuroanatomy of Motivated Behavior

A

-Critical Structures
~Hypothalamus and associated pituitary gland
*Sends information to other brainstem circuits to produce behavior
~Limbic system
~Frontal lobes
-Homeostatic Mechanism
~Process that maintains critical body functions within a narrow, fixed range

54
Q

Regulatory and Nonregulatory Behavior

A
-Regulatory Behavior
~Behavior motivated to meet the survival needs of the animal
~Controlled by homeostatic mechanisms, which involve the hypothalamus
~Examples: 
*Internal body temperature
*Eating and drinking
*Salt consumption
*Waste elimination
55
Q

Regulatory and Nonregulatory Behavior

-Nonregulatory Behavior

A

-Behavior unnecessary to meet the basic survival needs of the animal
-Not controlled by homeostatic mechanisms
-Most involve the frontal lobes more than the hypothalamus
-Strongly influenced by external stimuli
~Examples:
*Sexual behavior, parental behavior, aggression, food preference, curiosity, and reading

56
Q

Regulatory Function of the Hypothalamic Circuit

A

-Involvement in Hormone Secretions
~A principal function is to control the pituitary gland
-Pituitary Gland
~Endocrine gland attached to the bottom of the hypothalamus
~Its secretions control the activities of many other endocrine glands
~Known to be associated with biological rhythms

57
Q

Anatomy of the Hypothalamus

A

-Acts on both the endocrine system and the autonomic nervous system
-Controls variety of motivated behaviors (e.g., heart rate, feeding, sexual activity)
-Three regions of the hypothalamus
~Lateral Region
~Medial Region
~Paraventricular Region

58
Q

Hypothalamic Involvement in Hormone Secretions

A

-Lateral Region
~Contains nuclei and nerve tracts that connect the lower brainstem to the forebrain
~Medial Forebrain Bundle (MFB)
*Tract that connects structures in the brainstem with various parts of the limbic system
*Forms the activating projections from the brainstem to the basal ganglia and frontal cortex
*Dopamine-containing fibers are involved in reward and therefore contribute to many motivated behaviors
-Posterior Pituitary
~Neural tissue; continuation of the hypothalamus
-Anterior Pituitary
~Glandular tissue; synthesizes various hormones
-Releasing Hormones
~Peptides that are released by the hypothalamus and act to increase or decrease the release of hormones from the anterior pituitary
-Factors involved in controlling hypothalamic hormone-related activity
~Feedback Loops
*Control the amount of hormone that is released
~Neural Regulation
*Other brain regions (e.g., limbic system and frontal lobes) influence hormone release
~Experiential Responses
*Experience can alter the structure and function of hypothalamic neurons

59
Q

Hypothalamic Involvement in Generating Behavior

A

-Electrical stimulation of different nuclei in the hypothalamus will produce goal-directed behaviors, such as:
~Eating and drinking
~Digging
~Displaying fear
~Predatory or attack behavior
~Reproductive behavior
*Indistinguishable from normally occurring behaviors

60
Q

The Organizing Function of the Limbic Circuit

A
-The primitive limbic cortex comprises: 
~Cingulate gyrus
~Hippocampal formation
*Hippocampus
**Distinctive three-layered subcortical structure of the limbic system lying in the medial temporal region of the temporal lobe
**Plays a role in species-specific behaviors, memory, and spatial navigation
**Vulnerable to the effects of stress 
*Parahippocampal cortex
61
Q

Amygdala

A
  • Almond-shaped collection of nuclei located within the limbic system
  • Plays a role in emotional and species-specific behaviors
  • Receives input from all sensory systems
  • Many neurons respond to more than one sensory modality (multimodal)
  • Sends projections primarily to the hypothalamus and brainstem
62
Q

Prefrontal Anatomy and Connections

A

-Plays a key role in controlling executive functions such as planning movements
-Plays a role in specifying the goals toward which movement should be directed
-Controls the processes by which we select movements that are appropriate for the particular time and context
~May be cued by internal information (such as memory and emotion) or it may be made in response to context (environmental information)

63
Q

Prefrontal Cortex

A

-Receives connections from the amygdala, the dorsomedial thalamus, the posterior parietal (sensory association) cortex, and the dopaminergic cells of the ventral tegmental area
~Dopaminergic input influences how prefrontal neurons react to stimuli, especially emotionally arousing stimuli
-Inferior region projects to the amygdala and the hypothalamus: Influences autonomic nervous system
-Dorsolateral region projects to the posterior parietal cortex, the cingulate cortex, the basal ganglia, and the premotor cortex: Influences movement and memory

64
Q

Prefrontal Functions

A
  • Selecting behaviors appropriate to the particular time and place
  • Adapting behavior appropriately to the environmental context
  • Act much like a composer, selecting our actions
  • Frontal lobes are sometimes described as housing the brain’s executive functions
65
Q

Stimulating and Expressing Emotion

A

-Three Components of Emotion
~Autonomic Response (e.g., increased heart rate)
*Hypothalamus and associated structures
~Subjective Feelings (e.g., fear)
*Amygdala and parts of frontal lobes
~Cognitions (e.g., thoughts about the experience)
*Cerebral cortex

66
Q

Stimulating Emotion

-Explanations for Emotion

A

-James-Lange View of Emotion
~Physiological changes produced by the autonomic nervous system come first, and the brain interprets these changes as an emotion
~Evidence: Intensity of emotions in individuals with spinal cord damage depends upon the level at which the spinal cord is severed
-Somatic Marker Hypothesis (Damasio, 1999)
~Posits that “marker” signals arising from emotions and feelings act to guide behavior and decision making, usually an unconscious process

67
Q

Amygdala and Emotional Behavior

A
  • Involved in species-specific behaviors and emotion
  • Influences autonomic and hormonal responses via connections with the hypothalamus
  • Influences conscious awareness of the consequences of events and objects via connections with the prefrontal cortex
68
Q

Amygdala and Emotional Behavior

-Klüver-Bucy Syndrome

A

-Symptoms in monkeys
~Tameness and loss of fear
~Indiscriminate dietary behavior
~Greatly increased autoerotic, homosexual, and heterosexual activity with inappropriate object choice
~Tendency to attend to and react to every visual stimulus
~Tendency to examine all objects by mouth
~Visual agnosia (inability to recognize objects)

69
Q

Prefrontal Cortex and Emotional Behavior

A

-Damage to the prefrontal cortex has severe effects on social and emotional behavior
~Inability to experience and express their own emotions and to recognize the emotional expression of others
~Apathy and loss of initiative or drive
~Inability to plan and organize, leading to poor decision-making

70
Q

Emotional Disorders

A

-Major Depression
~Characterized by prolonged feelings of worthlessness and guilt, the disruption of normal eating habits, sleep disturbances, a general slowing of behavior, and frequent thoughts of suicide
~There is a genetic component
~Biological abnormality
*Early life stress may produce epigenetic changes in the prefrontal cortex
-Generalized Anxiety Disorder
~Persistently high levels of anxiety often accompanied by maladaptive behaviors to reduce anxiety; thought to be caused by chronic stress
-Phobia
~Clearly defined dreaded object or greatly feared situation
-Panic Disorder
~Recurrent attacks of intense terror that come on without warning and without apparent relation to external circumstances
-Most common treatment are the benzodiazepines, which augment GABA’s inhibitory effect

71
Q

Control of Regulatory and Nonregulatory Behavior

A
  • Regulatory behaviors maintain vital body-system balance, or homeostasis,
  • Nonregulatory behaviors are not controlled by a homeostatic mechanism
72
Q

Controlling Feeding

A

-Eating disorders entail being either overweight or underweight
-Obesity
~Excessive accumulation of body fat
-Anorexia Nervosa
~Exaggerated concern with being overweight that leads to inadequate food intake and often excessive exercising; can lead to severe weight loss and even starvation

73
Q

Digestive System and Control of Eating

A

-Mouth, stomach, intestine, gall bladder, pancreas, and anus
-Three types of nutrients are extracted, each of which is a specialized form of energy reserve:
~Lipids (fats)
~Amino acids (building blocks of proteins)
~Glucose (sugar)

74
Q

Digestive System and Control of Eating

A

-Body needs to be apprised of how well breakdown of food is proceeding
-Feedback mechanisms provide such information.
-When food reaches the intestines, it interacts with receptors there to trigger the release of at least 10 different peptide hormones
~Cholecystokinin (CCK)

75
Q

Hypothalamus and Control of Eating

A

-Aphagia
~Failure to eat; may be due to an unwillingness to eat or to motor difficulties, especially with swallowing; observed following lesions to the lateral hypothalamus
-Hyperphagia
~Disorder in which an animal overeats, leading to significant weight gain; observed following lesions to the ventromedial hypothalamus or the paraventricular nucleus of the hypothalamus
-Damage to the lateral and ventromedial hypothalamus and to the paraventricular nucleus has multiple effects
~Changes in hormone levels (especially insulin)
~Sensory reactivity (the taste and attractiveness of food is altered)
~Glucose and lipid levels in the blood
~Metabolic rate

76
Q

Cognitive Factors and Control of Eating

A

-Amygdala
~Projects to the hypothalamus; damage alters food preferences and abolishes taste-aversion learning
-Orbital prefrontal cortex
~Receives input from the olfactory bulb; damage may result in decreased eating because of diminished sensory responses to food odor and perhaps taste

77
Q

Controlling Drinking

A

-Two Kinds of Thirst
~Osmotic Thirst
*Results from an increased concentration of chemicals, known as solutes, in body fluids
*Drink water to restore ideal solute concentrations
~Hypovolumic Thirst
*Produced by a loss of overall fluid volume from the body
*Drink fluids, other than water, to restore nutrient

78
Q

Controlling Sexual Behavior

A

-Notwithstanding procreation, which is essential to the survival of the species, sexual behavior is nonregulatory
-Effects of Sex Hormones on the Brain
~A major organizing effect that gonadal hormones have on the brain is in the hypothalamus, especially the preoptic area of the medial hypothalamus
~Also operate in other nervous system regions
*Amygdala, the prefrontal cortex, and the spinal cord

79
Q

Organizing Effects of Sex Hormones

A

-Sexual Dimorphism
~Differential development of brain areas in the two sexes influenced by gonadal hormones (testosterone, estradiol)
~Estradiol masculinizes the male brain
*Aromatase converts testosterone to estradiol
*Alpha fetoprotein prevents estrogen from entering neurons
~Preoptic area of the hypothalamus is 5x as large in males as in females

80
Q

Activating Effects of Sex Hormones

A

-Adult female sexual behavior varies across the estrous cycle
~High estrogen levels are associated with sexual receptivity
~Rats: high estrogen is also associated with more dendritic spines on neurons in the hippocampus
-In adult males, testosterone levels influence the motivation to seek sexual behavior and the production of copulatory behavior

81
Q

Hypothalamus, Amygdala, and Sexual Behavior

A

-Ventromedial Hypothalamus
~Controls female mating posture (lordosis)
-Preoptic Area of the Medial Hypothalamus
~Controls copulatory behavior in males, but not sexual motivation
-Amygdala:
~Controls sexual motivation in males and possibly in females, as well (outside of their estrous cycle)

82
Q

Sexual Orientation, Sexual Identity, and Brain Organization

A

-Sexual Orientation
~A person’s sexual attraction either to the opposite sex or to the same sex or to both sexes
-Sexual Identity
~A person’s feeling either male or female

83
Q

Sex-Related Differences in Hypothalamus

A
  • Emerging evidence suggests that sex differences in the hypothalamus result from differences in gene methylation (epigenetics)
  • The hypothalamus of homosexual males differs from those in both males and females, suggesting a “third sex” with respect to hypothalamic structure
  • Differences in sexual orientation and gender identity appear to result from prenatal events that influence the organization and function of the brain, not from postnatal social or environmental experiences
84
Q

Cognitive Influences on Sexual Behavior

A
  • In addition to the amygdala and hypothalamus, the cortex must also have a role in controlling sexual behavior
  • However, the role of the cortex in sexual behavior is poorly understood
  • Damage to the frontal lobes can result in a loss of inhibition about sexual behavior or a loss of libido (sexual interest)
85
Q

Reward

A

-Reward may be a mechanism that evolved to help increase the adaptive fitness both of the entire species and of individual members of a species
~Maintain contact with some stimuli but not others
-Olds and Milner (1954)
~Rats will press a bar to self-administer electrical stimulation to specific sites in the brain (intracranial self-stimulation)
*Lateral hypothalamus and medial forebrain bundle are especially effective (part of mesolimbic dopamine system)

86
Q

Reward and Dopamine

A
  • Dopamine release shows a marked increase when animals are engaged in intracranial self-stimulation.
  • Drugs that enhance dopamine release increase self-stimulation; drugs that decrease dopamine release decrease self-stimulation; amount of dopamine released somehow determines how rewarding an event is
  • When animals engage in behaviors such as feeding or sexual activity, dopamine release rapidly increases in locations such as the nucleus accumbens
  • Highly addictive drugs such as nicotine and cocaine increase the level of dopamine in the nucleus accumbens.
87
Q

Reward

A

-Reward has two independent processes: wanting (incentive) and liking (evaluation of pleasure)
-Usually, wanting and liking occur together but this is not always the case
-Robinson and Berridge (2008)
~Wanting and liking have separable neural systems
*Wanting: Involves dopamine
*Liking: Involves opioid and benzodiazepine-GABA systems
-Reward pathways are diffuse and the size and activity of these pathways are related to the intensity of reward (noted in both smokers and gamblers)