MCAT Psychology, MCAT Psych/Sociology from 132 Scorer

Stretch Reflex

One muscle contracts while being stretched while the antagonist muscle relaxes. Regulates muscle length

Signs of lower motor neuron disease

decrease in muscle tome and decreased reflexes

Signs of upper motor neuron disease

Increased muscle tone and increased reflexes

Clonus

Muscle spasms involving repeated contractions. Example: the ankle contracts and flexes quickly back and forth.

Hypertonia

A state of increased muscle tension or tonicity

Babinski Reflex (Extensor Plantar Response)

A reflex characterized by upward movement of the great toe and an outward movement of the rest of the toes when the sole of the foot is stroked. Normal in infants.

Lateral Hypothalamus

Involved in regulation of eating. Lesions result in fasting and weight loss whereas stimulation increases food intake.

Ventromedial Hypothalamus

Involved in feelings of satiety. Lesions result in overeating.

Leptin

Regulates body fat and food intake. Maintains normal body weight by providing sensation of satiety. Found in hypothalamus. Secreted by fat cells.

Sexual Response Cycle (durations)

Arousal: Several minutes to hours

Plateau: A few minutes

Orgasmic: A few seconds

Resolution: A few hours

Prolactin

A hormone which modulates sexual arousal and refractory phase

Endorphins

Hormones having an analgesic effect. Released after having sex

Oxytocin

Promotes bonding between partners during/after sex

Theories on Motivation and Cognition (description and example)

Extrinsic Motivation

An external incentive i.e getting paid to do something

Intrinsic Motivation

The pleasure of participating in an activity i.e studying a subject that is interesting

Drive Theory

A disruption in homeostasis leads to a feeling of tension which in turn creates a drive. Drive serves as a motivation to reduce the tension

Amotivation

lack of motivation

Manslow's Hierarchy of Needs (list from lowest priority to highest)

Incentive Theory

Emphasizes interaction between environmental incentives and an organism's drive state

Positive Reinforcement

Desirable event or stimulus that increases the probability of an organism emitting a particular behavior

Negative Reinforcement

Undesirable event or stimulus that decreases the probability of an organism emitting a particular behavior

Stressor

Anything that results in physical or emotional stress

Appraisal Theory

The proposal that people's evaluations of a situation determine the emotions they feel in response.

Primary Appraisal

The initial evaluation of a situation's relevance to one's personal preferences and the likelihood of reaching one's goals. Three categories: irrelevant, benign/positive, or stressful/negative

Secondary Appraisal

One's evaluation of his or her ability to cope with the consequences of an interaction with the environment. If primary appraisal is negative: appraisal of harm (how much damage has been done), threat (how much damage could be caused), and challenge (how the problem could be solved)

Stress effects on the heart

increase in blood pressure -----> plaque and vascular disease ----> coronary artery disease

Stress effects on metabolism

increase cortisol and glucagon-----> increased levels of blood glucose ----> metabolic syndrome, heart disease

Stress effects on reproduction

Impotence, impaired sexual function

Stress effects on immune system

Decrease in immune response

Stress effects on cognition

Atrophy of hippocampus changes emotional responses: anger, anxiety, poor coping skills

Learned helplessness

a psychological phenomenon in which a subject endures repeated aversive stimuli that are beyond its control and subsequently does nothing to escape the aversive stimuli when enabled to do so; linked to depression

Emotional responses to stress

depression and anhedonia (inability to feel pleasure); also anger, anxiety, and addiction

4 categories of stressors (description, example)

quotidian means everyday, unusual

Autonomic nervous

The division of the peripheral nervous that regulates internal bodily functions and is the mechanism in homeostatic control. Comprises sympathetic and parasympathetic nervous systems.

How does the sympathetic nervous system respond to stress?

The sympathetic nervous system responds to stress by triggering the "fight-or-flight" response, increasing heart rate, dilating bronchi, and redirecting blood flow to muscles.

How does the parasympathetic nervous system respond to stress?

The parasympathetic nervous system counteracts the stress response by promoting "rest-and-digest" functions, slowing heart rate, constricting bronchi, and stimulating digestion.

Endocrine response to stress

adrenal medulla releases catecholamines (epinephrine, norepinephrine)

adrenal cortex releases glucocorticoids (cortisol)

Endocrine response to stress

adrenal medulla releases catecholamines, adrenal cortex releases glucocortids (cortisol)

Tend and befriend response

Humans, especially females, often manage stress by tending to children and seeking social connection

General Adaptation Syndrome (3 stages)

The physiological consequences of severe stress in three stages:

1.Alarm stage: mobilize resources

2.Resistance Phase: cope with stressor

3.Exhuastion Phase: reserves depleted

Coping

Actions taken in dealing with stressful situations

What are most effective coping techniques?

Perceived control: The belief that you are in control of the situation

Optimism: Expecting good things to happen

Social Support: Encouragement from friends and family

Adaptive Coping Techniques

Anticipation: Anticipating the effects of the stressor

Social Coping: Seeking out social support

Meaning focused coping: Understanding the role played in your life by the stressful situation

Maladaptive Coping Mechanisms

Unsucessful attempts to decrease the anxiety without attempting to solve the problem.

The anxiety remains. Ie. Escape, murder, avoidance

What are characteristics of learned behavior?

Non-inherited: learned through observation and experience Extrinsic: will not develop if organism is isolated

Permutable: Can be altered through learning and experience

Progressive: Can change over time

Low effort Syndrome

A sociological phenomenon whereby members of a minority group put forth minimal effort in the belief that their efforts will be for naught due to discrimination

Game Theory

The study of mathematical models of strategic interactions.

Evolutionary Game Theory

Applies to evolutionary biology to predict altruism, mating behavior, availability of resources.

Hypothalamus

Responsible for the regulation of many metabolic processes such as body temperature and hunger, along with other activities of the autonomic nervous system. Keeps the body in a state of homeostasis

Pituitary Gland

The anterior lobe secretes certain hormones such as growth hormone and prolactin, while the posterior lobe secretes vasopressin and oxytocin

Thyroid Gland

Regulates metabolic rate and and growth in children. Secretes the hormones T3 and T4.

Parathyroid Gland

Controls calcium and phosphate metabolism

Adrenal Glands

Cortex: produces cortisol and androgens

Medulla: produces epinephrine and norepinephrine

Gonads

Ovaries an Testes: Releases progesterone and estrogen in females and testosterone in males

Pancreas

Gland which secretes insulin and glucagon

Primary and Secondary Visual Cortex

Primary (Striate) Cortex: Receives visual input from the lateral geniculate nucleus

Secondary: Further processing of visual input in terms of motion, shape, and position

Lateral Geniculate Nucleus (LGN)

Located in the thalamus, acts as a relay station for visual information on its way from retina to the primary visual cortex

Prefrontal Cortex

Functions in executive functions such as attention, planning, working memory, and expression of emotions

Cerebellum

Part of the hindbrain which produces smooth muscular movements and maintains equilibrium

Brainstem

Connects the cerebrum with spinal cord. Includes midbrain, pons, and medulla oblongata. Controls salivation, respiration, heartbeat, and digestion

Brain Anatomy (Cerebrum)

What is hemispheric lateralization?

Certain functions are controlled more by one cerebral hemisphere than the other

What is the left hemisphere responsible for?

language and analysis

What is the right hemisphere responsible for?

music, emotions, spatial orientation

Frontal Lobe

Motor Cortex: body movement

Prefrontal Cortex: executive functions (panning, decision making, problem solving)

Broca's area: speech production

Parietal Lobe

Somatosensory Cortex: Perception of touch, temp, body potion, and pain. Spatial sense and navigation

Occipital Lobe

Processes visual input

Temporal Lobe

Wernicke's Area: responsible for language comprehension. Also functions in sound perception and memory formation

Brain Anatomy (Brainstem)

Reticular Formation: Involved in arousal, alertness, sleep-wake cycles

Cranial Nerves: 12 extending out of the brainstem

Pons: Functions in sleep and relaxing

Medulla Oblongata: breathing, heartbeat, blood pressure

CT Scan (Computerized tomography)

X-ray of brain structure, shot from many angles and images with horizontal slices of the brain are generated. Inexpensive scan of brain structure. Larger findings such as tumors and blood clots.

MRI (Magnetic Resonance Imaging)

uses magnetic fields, radio waves, computerized enhancement to map out brain structure with higher soft tissue resolution than CT. Used for the anatomy and physiological processes of the body.

EEG

electroencephalogram. Used to record the electrical activity of the brain

MEG

Magnetoencephalogram. Maps brain electrical activity using magnetic fields. Higher res than EEG

fMRI

Functional MRI, allows visualization of any active brain area. new variation of MRI that monitors blood flow and o2 consumption in the brain to identify areas of high activity. Can map activity over time with great precision.

PET (positron emission tomography) scanning

can also examine brain function, mapping activity over time. Uses radioactively tagged chemicals introduced in brain as markers of blood flow/metabolic activity. This can be monitored with X-rays. Provides color-coded map indicating which areas are active during certain stimulus.

Central Nervous System

Brain and Spinal Cord

Peripheral Nervous System

The nervous system outside of the brain and spinal cord

Somatosensation

The perception of touch, temp, body position (proprioception), and pain. Subset of the sensory nervous system

Afferent Neurons

sensory neurons, carry signals to the central nervous system

Efferent Neurons

motor sensory, carry signals from central nervous system to the muscles

Contralateral Control

Left brain controls right side of body; right brain controls left side of body. Exception: Smell

Dominant Hemisphere

In most people the left. The left produces language and math. Right produces music and emotion

Gray vs White Matter

Gray: Neuronal cell bodies, dendrites, synapses

White Matter: mylinated axons of neurons

Neuromuscular Junction

Synapse between motor neuron and a muscle fiber

Upper vs Lower Motor Neurons

Upper motor neurons are located in the central nervous system. Lower motor neurons are located in the synapses between the peripheral nervous system and the skeletal muscle, forming the neuromuscular junction

Receptor

A specialized cell in the sensory system that responds to particular stimuli in the environment. Responsible for stimulus in transduction (sensation turning into electrical signals). Examples: rods and cones in the eyes and hair cells in the cochlea

Mechanoreceptors

Receptors in the ear that translate sound waves into nerve impulses; touch receptors in the skin; and proprioceptors in the joints and muscles

Glutamate

Excitatory neurotransmitter responsible for increased cortical arousal

GABA and Glycine

Inhibitory. GABA: Brain, Glycine:spinal cord

Acetylcholine

Plays a role in memory, learning, attention, arousal and involuntary muscle movement. Lack of acetylcholine is associated with Alzheimer's disease

Histamine

Nuerotransmitter for the brain, spinal cord, and uterus. Also acts to promote a innate immune response (unlike cytokines which are merely for cell to cell communication during immune response)

Norepinephrine (Adreniline)

Functions both as a neurotransmitter and hormone. Mobilizes the brain and body for action

Serotonin

Found in the raphe nucleus and other parts of the central nervous system. Plays a role in emotional processing, mood, appetite, sleep, and pain processing

Dopamine

Plays a role in motor behavior and is implicated in numerous emotional states, drug addiction, and reward motivated behavior. Low-levels lead to Parkinson's disease

Amino Acid Neurotransmitters

Glutamte is excitatory; GABA and glycine are inhibitory

Peptide Neurotransmitters (neuropeptides)

Opioids (e.g. endorphins); involved in pain perception

Monoamine Transmitters

catecholamines (dopamine, norepinephrine, epinephrine)

indolamine (serotonin)

Mating

Activities involved in reproduction: courtship, mate selection, copulation

Conspecific

A member of the same species