Biological Bases of Behavior Part 1 (Modules 9-18)

AP Psychology Unit 1 part 1

What do biological psychologists do?

use advanced technologies to study the links between biological (genetic, neural, hormonal) processes and psychological processes; They work from a biological perspective; are announcing discoveries about the interplay of biology, behavior, and mind

What are four things that researchers are seeking to understand the biology of the mind have discovered?

1. our adaptive brain is wired by our experiences

2. among the body's cells are nerve cells that conduct electricity and "talk" to one another by sending chemical messages across a tiny gap that separates them

3. specific brain systems serve specific functions

4. we integrate information processed in these different brain systems to construct our experience of sights and sounds, meaning and memories, pain and passion

What is meant that humans are considered biopsychosocial systems?

we are each a system composed of subsystems that are in turn composed of even smaller subsystems

Why is it a benefit that there is not much difference between the brains of humans and animals?

similarities allow researchers to study simple animals to understand the neural systems we explore; studying other mammals' brains helps understand the organization of our own

What are neurons?

nerve cells that are the basic building block of the nervous system

What is the function of the cell body in a neuron?

contains nucleus; the cell's life support center

What is the function of the dendrite in a neuron?

neuron's bushy, branching extensions that receive and integrate messages, conducting impulses toward the cell body

What is the function of the axon in a neuron?

the neuron extension that passes messages through its branches to other neurons or to muscles or glands

What is the function of the myelin sheath in a neuron?

fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next

How is the myelin sheath related to multiple sclerosis?

if the myelin sheath degenerates, the communication to muscles slows, with eventual loss of muscle control

What are glial cells?

cells in the nervous system that support, nourish, and protect neurons; they also play a role in learning, thinking, and memory

What is a neuron's action potential?

a neural impulse; a brief electrical charge that travels down an axon

Describe the chemical events that allow neurons to fire.

Neurons fire when ions flow through their selectively permeable membrane, disrupting the resting potential. This change in electrical charge generates an action potential, allowing the neuron to transmit a signal.

How do the security parameters change when a neuron fires? How often can this process repeat?

axon opens its gates, sodium ion flood in, the loss of inside/ outside difference (depolarization) causes the next axon channels to open, like falling dominos; temporary inflow of positive ions is the neural impulse (action potential); 100-1000x/sec

What is depolarization?

the loss of the inside/outside charge difference causes the next section of axons to open like falling dominos

What is action potential?

the change in electrical potential associated of an impulse in a nerve cell; temporary inflow of positive ions

What are excitatory signals?

increase likelihood that neuron will fire (like pushing a gas pedal); if these signals > inhibitory signals, combined signals trigger action potential

What are inhibitory signals?

decrease likelihood that neuron will fire (like pushing breaks)

What is the threshold?

the level of stimulation required to trigger a neural impulse

What is the refractory period?

a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state

What is the all-or-none response?

a neuron's reaction of either firing (with a full-strength response) or not firing.

Where is the synapse?

junction between the axon tip of the sending neuron and dendrite or cell boy of the receiving neuron

Relating to the synapse, what is the tiny gap at the junction called?

synaptic cleft/gap

What are neurotransmitters?

chemical messengers that cross the synaptic gaps between neurons

What happens after a neurotransmitter is released?

neurotransmitters travel across the synapse and bind to the receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse

What occurs during reuptake?

neurotransmitter unlocks tiny channels at the receiving site and electronically charged atoms flow in, exciting or inhibiting the receiving neuron's readiness to fire; excess neurotransmitters drift away, are broken down by enzymes, or are reabsorbed by the sending neuron

Particular neurotransmitter affect specific: ____ & ____

behaviors and emotions

What is the function of Acetylcholine (ACh)?

enables muscle action, learning, memory

What is an example of malfunctions of the neurotransmitter Acetylcholine (ACh)?

with alzheimer's disease, ACh-producing neurons deteriorate (all movement)

How to remember the neurotransmitter Acetylcholine?

ACh: Alzheimer's, muscle Action; ACE EXAM

What is the function of dopamine?

influences movement, learning, attention, and emotion, PLEASURE/REWARD

What is an example of malfunctions of the neurotransmitter dopamine?

oversupply linked to schizophrenia; undersupply linked to tremors and decreased mobility in Parkinson's disease

What is a way to remember the neurotransmitter dopamine?

dopaMINE: MINE MINE MINE; pursuit of pleasure

What is the function of the neurotransmitter serotonin?

affects mood, hunger, sleep, and arousal

What is an example of malfunctions of the neurotransmitter serotonin?

undersupply linked to depression; some antidepressant drugs raise these levels; dreams

What is a way to remember the neurotransmitter serotonin?

seROTONin: avoid rotten FOOD, MOOD, SLEEP

What is the function of the neurotransmitter norepinephrine?

helps control alertness and arousal; heightened sensitivity

What is an example of malfunctions of the neurotransmitter norepinephrine?

undersupply can depress mood; involved in sleep cycle

What is the function of the neurotransmitter GABA (gamma-aminobutyric acid)?

a major inhibitory neurotransmitter

What is an example of malfunctions of the neurotransmitter GABA?

undersupply linked to seizures, tremors, and insomni; anxiety-related distress

What is a way to remember the neurotransmitter GABA?

G et

A

Break

Adjustment

What is the function of the neurotransmitter glutamate?

a major excitatory neurotransmitter; involved in memory; enhances learning by strengthening synaptic connections

What is an example of malfunctions of the neurotransmitter glutamate?

oversupply can overstimulate the brain, producing migraines or seizures

What is a way to remember the neurotransmitter glutamate?

EXCITED to be GLUed to your MATE

What is the function of the neurotransmitter epinephrine (adrenaline)?

neurotransmitter and hormone that boosts energy in chemicals in "fight or flight"

What is the function of the neurotransmitter substance p?

similar to endorphin; body's PAIN neurotransmitter; works with endorphins to regulate pain; signals body IN pain

[endorphins triggered to inhibit pain signal]

What are endorphins and give an example of what they can do?

natural painkiller; "morphine within" natural, opiate-like neurotransmitters linked to pain control and pleasure

• runner' high, prolonged exercise, acupuncture, indifference to pain in severe injuries; triggered to inhibit pain signal

What is a way to remember endorphins?

ENDorphins END pain

What happens when the brain is flooded with opiate drugs such as heroin and morphine?

brain maintains its chemical balance by suppressing its own natural opiates; when the drug is withdrawn, the brain may be deprived of any form of opiate, causing intense discomfort

What is an agonist?

a molecule that increases a neurotransmitter's action

What is an antagonist?

a molecule the decreases or blocks a neurotransmitter's action/ production/ release

What is the nervous system?

the body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems

What is the central nervous system?

brain and spinal cord

What is the peripheral nervous system?

the sensory and motor neurons that connect the central nervous system to the rest of the body

What makes up nerves?

bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sense organs

What are the four parts of the peripheral nervous system?

somatic nervous system

autonomic nervous system

sympathetic nervous system

parasympathetic nervous system

What makes up the somatic nervous system?

the division of peripheral nervous system that controls the body's skeletal muscles (skeletal nervous system)

What makes up the autonomic nervous system?

the part of the peripheral nervous system that controls the glands and muscles of the internal organs

Where is the sympathetic and parasympathetic nervous system located?

autonomic nervous system

What is the sympathetic nervous system?

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations; "fight or flight"

What is the parasympathetic nervous system?

the division of the autonomic nervous system that calms the body, conserving its energy; "rest and digest"

What does it mean "the brain enables our humanity"?

thinking, feeling, and acting; tens of billions of neurons, each communicating with thousands of other neurons, yield and ever-changing wiring diagram

Approximately how many neurons in the central nervous system?

86 billion

What are neural networks?

the brain's neurons cluster into work groups

Neurons that ___ together ___ together, helping learning occur

FIRE, WIRE

What is the spinal cord, and how does it work?

two-way information highway connecting the peripheral nervous system and the brain

What are reflexes?

a simple, automatic response to a sensory stimulus, such as the knee-jerk response

What happens if the spinal cord is severed?

You would be out of touch with your body. You would lose all sensation and voluntary movement in body regions with sensory and motor connections to the spinal cord below its point of injury.

What is the endocrine system?

the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream

What are hormones?

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues

What happens when hormones act on the brain?

they influence our interest in sex, food, and aggression

How is the endocrine system similar to the nervous system?

both produce molecules that act on receptors elsewhere

How are the endocrine and nervous systems different?

nervous system: zips messages from the eye to the brain in fraction of a second

endocrine system: messages trudge along in the bloodstream; taking several seconds to travel; gland to the target issue

What is the pituitary gland? Why is it the most influential endocrine gland?

under the influence of the hypothalamus, it regulates growth (physical development) and controls other endocrine glands

What is a lesion?

tissue destruction; a brain lesion is a naturally or experimentally caused destruction of brain tissue

how else can scientists observe brain functions?

electrically, chemically, or magnetically stimulate various parts of the brains and note the effects

What is an EEG; electroencephalogram, and for what purpose is it used?

an amplified recording of the waves of electrical activity sweeping across the brain's surface; these waves are measured by electrodes placed on the scalp

What is magnetoecenphatography?

MEG; brain imaging technique that measures magnetic fields from the brain's natural electricity activity

What is the purpose of this neuroimaging technique: CT computed tomography scan?

a series of x-ray photos taken from different angles and combined by computer into a composite representation of a slice of the brain's structure

What is the purpose of this neuroimaging technique: PET positron emission tomography?

a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given tasks

What is the purpose of this neuroimaging technique: MRI magnetic resonance imaging?

a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue; show brain ANATOMY

What is the purpose of this neuroimaging technique: fMRI functional magnetic resonance imaging?

a technique for revealing blood flow, and therefore, brain ACTIVITY by comparing successive MRI scans; show brain FUNCTION and STRUCTURE

List a couple examples of how animals' capacities come from brain structures.

• primitive animals (sharks): a not so complex brain; mostly regulates basic survival functions (breathing, resting, feeding)

• lower mammals (rodents): a more complex brain; enables emotion and greater memory

What is the hindbrain?

medulla, pons, cerebellum; directs essential survival functions (breathing, sleeping, wakefulness, coordination, and balance)

What is the midbrain?

found atop the brainstem; connects the hindbrain with the forebrain, controls some motor movement, and transmits auditory and visual information

What makes the brain of advanced mammals more complex?

(humans) a brain that processes more information enables increased foresight as well

What is the brainstem?

the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; responsible for automatic survival functions

What is the medulla?

the base of the brainstem; controls heartbeat and breathing

What is the reticular formation/ reticular activated system?

a nerve network through the brainstem to the thalamus and plays an important role in controlling arousal; filters incoming sensory stimuli

What is the thalamus?

sensory control center; atop the brainstem;

-directs messages to the sensory receiving areas in the cortex and

-transmits replies to the cerebellum and medulla;

-SENSORY SWITCHBOARD; except smell

What is the cerebellum?

the "little brain" at the rear of the brainstem; functions include

-processing sensory input,

-coordinating movement output and balance, and

-enabling nonverbal learning and

-memory (procedural memories): tying a shoe or riding a bicycle

These older brain functions all occur without ___

any conscious effort

What is the limbic system?

emotional headquarters

amygdala, hypothalamus, hippocampus

located below the cerebral hemispheres, associated with emotions and drives

What is the amydala?

lima-bean-sized neural clusters in the limbic system; linked to emotion

Is the amygdala the only area that controls rage and fear? Explain.

the brain is not organized into neat structures that correspond to our behavior categories; when we feel afraid, there is neural activities in many areas of our brain

What is the hypothalamus?

A neural structure lying below the thalamus; it

-directs several maintenance activities (eating, drinking, body temperature),

-helps govern the endocrine system via the pituitary gland, and is

-linked to emotion and reward.

Why is it referred to as the reward center?

rather than attribute human feelings to rats, today's scientists refer to reward centers, not "pleasure centers"

What is the hippocampus?

a neural center located in the limbic system; helps process explicit conscious memories of names, images, facts and events

What is the cerebrum?

newer neural networks within the cerebellum form specialized work teams that enable our perceiving, thinking, and speaking

What is the cerebral cortex?

The intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information-processing center