Unit 1: biological bases of behavior

twin studies

Examines similarities and differences between identical (monozygotic) and fraternal (dizygotic) twins to assess the relative influence of genetics and environment on traits and behaviors.

adoption studies

Investigates similarities between adopted children and their biological and adoptive families to assess the impact of genetics versus environment on various traits and behaviors.

family studies

Analyzes similarities and differences among family members, including parents and siblings, to understand the interplay of genetics and environment in shaping traits and behaviors within a family unit.

heredity

the transmission of genetic information from biological parents to offspring.

genetic predisposition

the inherited likelihood of developing specific traits or conditions due to genetic factors from biological parents.

eugenics

the belief in improving the genetic quality of a human population by controlling reproduction to increase desirable traits and decrease undesirable ones.

Cerebral Cortex

the outer layer of the brain, responsible for higher-level cognitive functions, including thinking, perceiving, and decision-making.

Corpus Callosum

bundle of nerve fibers that connects the two hemispheres, messages move from one side of the brain to the other 

Lobes of the Brain

The lobes of the brain refer to the four main regions or sections into which the cerebral cortex, the outer layer of the brain, is divided.

Association Areas

They're parts of the brain that take information from all over the place—like what we see, hear, smell, and touch—and put it together to help us understand the world around us.

frontal lobes

located at the front of the brain and are involved in higher-level cognitive functions, including decision-making, problem-solving, planning, and personality expression.

Prefrontal Cortex

a region of the brain located in the frontal lobe, responsible for higher-level cognitive functions and executive functioning.

Executive Functioning

a set of cognitive processes that enable individuals to plan, organize, strategize, focus attention, regulate emotions, and manage time effectively.

damage/dmg to prefrontal cortex

Damage can lead to a loss of moral compass and display violent or offensive behavior

Motor Cortex

region of the brain located in the frontal lobe, responsible for planning, executing, and controlling voluntary movements of the body.

damage/dmg to motor cortex

Damage leads to loss of movement on opposite side of the body

Broca’s Area

located in the left hemisphere of the brain, specifically in the frontal lobe, that is responsible for speech production and language processing.

Broca’s Aphasia

language disorder caused by damage to Broca's area in the left hemisphere of the brain, often resulting from stroke or brain injury.

parietal lobes

located at the top of the brain and are primarily responsible for processing sensory information from the body, such as touch, temperature, and spatial awareness.

damage to parietal lobes

Damage leads to loss of touch and feeling

Somatosensory Cortex

region of the brain located in the parietal lobe, responsible for processing sensations from the skin, muscles, and joints.

damage/dmg to Somatosensory Cortex

Damage leads to loss of feeling in legs without damage to nerves or spinal cord

occipital lobes

located at the back of the brain and is primarily responsible for processing visual information received from the eyes.

damage/dmg to occipital lobes

Damage to the eyes can cause vision/issues/ blindness

temporal lobes

located on the sides of the brain and are involved in processing auditory information, language comprehension, and memory formation.

damage/dmg to temporal lobes

Damage can lead to difficulties hearing and recognizing faces and hearing ringing noises

Wernicke’s Area

region located in the left hemisphere of the brain, specifically in the temporal lobe, that is involved in language comprehension and understanding spoken and written language.

• It helps to interpret the meaning of words and sentences, allowing individuals to comprehend and process language.

wernickes aphasia

if the area is damaged people cannot create sentences that make sense, and they cannot understand what people say to them.

Exhibit fluent speech but have difficulty understanding spoken and written language, as well as producing meaningful and coherent speech.

limbic system

The limbic system, located beneath the cerebral cortex, is a set of brain structures involved in emotions, memory, and motivation.

Reward Center

network of brain structures, primarily located in the limbic system, that processes pleasurable experiences and reinforces behaviors associated with them.

Reticular Activating System (RAS)

 a network of neurons located in the brainstem that plays a critical role in regulating arousal, attention, and consciousness.

hypothalamus

a small but powerful structure located below the thalamus, responsible for regulating various essential bodily functions, including hunger, thirst, body temperature, and the sleep-wake cycle

• helps maintain homeostasis

• controls the pituitary gland (stress, growth and reproduction) by secreting/producing hormones

lateral hypothalamus (LH)

 regulates feelings of hunger.

dmg/damage to lateral hypothalamus (LH)

can cause you to never feel hungry

Ventromedial hypothalamus (VH)

regulates feelings of satiety (fullness).

damage/dmg to Ventromedial hypothalamus (VH)

can cause you to never feel full

pituitary gland

small pea-sized gland located at the base of the brain

• Plays a critical role in coordinating hormonal activity and maintaining homeostasis in the body.

• Regulates stress, growth and reproduction, including some parts of pregnancy and childbirth

amygdala

small, almond-shaped structure located deep within the brain's temporal lobes

• A structure in the limbic system involved in emotion, particularly fear and aggression. (fight or flight)

damage/dmg to amygdala

damage can make you lose your sense of fear or become paszive

hippocampus

curved structure located within the brain's temporal lobes involved in learning and memory

damage/dmg to hippocampus

memory problems/Alzheimer's

brainstem

the oldest and most primitive part of the brain, responsible for basic life-sustaining functions such as breathing, heart rate, and sleep-wake cycles.

• automatic survival functions such as breathing, swallowing, heart rate, blood pressure, consciousness

• includes: pons, medulla, and midbrain

thalamus

a relay station in the brain that processes and relays sensory information, such as sight, sound, touch, and taste, to the cerebral cortex.

midbrain

Just below the Thalamus and helps with visual and auditory

pineal gland

Right of the Thalamus and uses the light/dark to increase melatonin

pons

The larger swelling above the medulla, the bridge between cerebral hemispheres and both medulla & cerebellum

• Role in several autonomic functions such as stimulating breathing and controlling sleep cycles

medulla

The base of the brainstem that controls vital life-sustaining functions like heartbeat and breathing. Triggers vomiting and sneezing

forebrain

consists of the thalamus, hypothalamus, amygdala, and the hippocampus. The hypothalamus,

cerebellum

A part of the brain at the back of the skull that coordinates and regulates muscular activity

damage/dmg to medulla

problems controlling heart rate and breathing, as well as swallowing and sneezing

damage/dmg to cerebellum

problems such as motor skills (handwriting), balance, coordination, posture and judging distances

nervous system

body's communication network, consisting of a complex system of nerves, neurons, and specialized cells.

Central Nervous System (CNS)

consists of the brain and spinal cord. It serves as the command center of the body, responsible for processing information, coordinating responses, and regulating bodily functions.

Peripheral Nervous System (PNS)

consists of all the nerves and ganglia outside the brain and spinal cord.

Autonomic Nervous System

division of the peripheral nervous system that regulates involuntary bodily functions, and consists of the sympathetic nervous system and the parasympathetic nervous system.

sympathetic nervous system (SNS)

responsible for activating the body's "fight or flight" response in times of stress or danger.

• Increases heart rate, dilates airways, and redirects blood flow to essential organs, preparing the body to respond to perceived threats.

Parasympathetic Nervous System

responsible for promoting relaxation and restoring the body to a calm state after experiencing stress or danger.

somatic nervous system

division of the peripheral nervous system responsible for controlling voluntary movements and relaying sensory information from the body to the central nervous system.

neurons

specialized cell that serves as the building block of the nervous system, transmitting electrical and chemical signals throughout the body.

• It consists of three main parts: the cell body (soma), dendrites, and axon.

motor neurons

nerve cells that transmit signals from the central nervous system (brain and spinal cord) to muscles, glands, and organs, initiating and controlling voluntary and involuntary movements.

• They receive commands from the brain or spinal cord and convey these signals to muscles, causing them to contract or relax.

sensory neurons

specialized nerve cells that transmit sensory information from sensory receptors, such as those in the skin, muscles, and organs, to the central nervous system (brain and spinal cord).

• They detect various stimuli, including touch, temperature, and environmental changes, and convert these stimuli into electrical signals that can be processed by the brain.

interneurons

nerve cells that serve as connectors within the central nervous system, relaying signals between sensory neurons and motor neurons.

reflex arc

neural pathway that controls reflex actions, allowing for rapid, automatic responses to sensory stimuli without conscious thought (primitive reflexes).

• Sensory neurons detect stimuli and send signals to the spinal cord. Interneurons relay this information to motor neurons, which trigger reflexive muscle or gland responses

dendrites

withdrawing a hand from a hot surface.

Receive signals, receptor sites are the lock where the neurotransmitter molecule fits into

Receive signals, receptor sites are the lock where the neurotransmitter molecule fits into

soma

The cell body of the neuron responsible to maintain the cell and keep the neuron functional (nucleus included)

axon

Fiber that extends from the cell body to the terminal endings of neurons, its job is to carry messages out to other cells

myelin sheath

Layer of fatty substance produced by certain glial cells, wraps around the axon to protect the nerve fiber from damage, insulating sheath, speeds up the neural message

axon terminals

Tips at the end of the axon, send signal to other neurons

Neural Transmission

the process by which neurons communicate with each other through electrical and chemical signals. (the graph chart thing)

threshold

 the level of stimulation required to trigger an action potential in a neuron. It is the minimum amount of stimulation necessary to produce a response.

action potenial

brief electrical impulse that travels along the axon of a neuron. The rapid movement of ions during an action potential disrupts the ion balance across the cell membrane and _____ occurs

• It occurs when the neuron receives a stimulus that causes the inside of the cell to become more positively charged than the outside.

All-or-Nothing Principle

states that once a neuron reaches its threshold of excitation, it will fire an action potential at full strength.

Depolarization

phase of action potential where the inside of the neuron becomes less negative compared to the outside due to the influx of positively charged ions, such as sodium ions, through ion channels in the cell membrane.

refractory period

brief period following an action potential during which a neuron is unable to generate another action potential.

• This period occurs because the neuron's sodium channels are temporarily inactivated and the cell membrane returns to its resting state.

• when the Na/K-ATPase pump uses ATP to move sodium ions out of the cell and potassium ions into the cell, restoring the resting ion gradients necessary for future action potential

Resting Potential

the stable, negative electrical charge that exists across the cell membrane of a neuron when it is not actively transmitting signals.

• It is maintained by the unequal distribution of ions, with more sodium ions outside the cell and more potassium ions inside.

reuptake

process in which neurotransmitters that have been released into the synapse are reabsorbed by the presynaptic neuron from which they were originally released.

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