unit 4 biological basis: brain and nervous system

vocab

Heredity

The process through which genetic information is transmitted from parents to offspring, influencing various traits and characteristics.

Environmental Factors

External conditions and influences, such as family, culture, and climate, that can affect an individual's development and traits.

Nature vs. Nurture

A debate concerning the relative influence of genetics and environment on psychological traits and behaviors.

Eugenics

The study of or belief in improving the genetic quality of the human population through selective breeding and other interventions.

Evolutionary Perspective

Examines how evolutionary theory explains the development of behaviors and traits that enhance survival and reproduction.

Twin Studies

Research designs that involve comparing the similarities of identical and fraternal twins to understand the influence of genetics and environment on traits.

Family Studies

Assess the prevalence of traits or disorders within families, highlighting hereditary patterns across generations.

Adoption Studies

Investigate the behavior and traits of adopted individuals compared to their biological and adoptive families to understand genetic versus environmental influences.

Central Nervous System (CNS)

Consists of the brain and spinal cord, serving as the main control center for processing and transmitting information throughout the body.

Peripheral Nervous System (PNS)

Includes all nerves outside the CNS, facilitating communication between the central nervous system and the rest of the body.

Autonomic Nervous System

Controls involuntary bodily functions, regulating heart rate, digestion, and respiratory rate.

Somatic Nervous System

Oversees voluntary movements and the transmission of sensory information to the CNS.

Parasympathetic Nervous System

A division of the autonomic nervous system that promotes relaxation and conserves energy by slowing heart rate and increasing digestive activity.

Sympathetic Nervous System

A division of the autonomic nervous system that prepares the body for 'fight or flight' responses during stressful situations.

Neurons

The fundamental units of the nervous system that transmit information through electrical and chemical signals.

Glial Cells

Provide support, nourishment, and protection for neurons, playing essential roles in maintaining homeostasis and facilitating communication.

Reflex Arc

The neural pathway that mediates a reflex action, allowing a rapid response to stimuli without involving conscious thought.

Sensory Neurons

Transmit sensory information from the body to the central nervous system for processing.

Motor Neurons

Convey signals from the central nervous system to muscles and glands, facilitating movement and responses.

Interneurons

Neurons that connect sensory and motor neurons within the central nervous system, processing information and coordinating responses.

All-or-Nothing Principle

States that a neuron either fires an action potential or does not, with no intermediate responses.

Depolarization

The process by which a neuron's membrane potential becomes less negative, ultimately leading to an action potential.

Refractory Period

The recovery phase post-action potential during which a neuron is less responsive to stimulation.

Resting Potential

The electrical charge difference across a neuron's membrane when it is not transmitting a signal.

Reuptake

The process by which neurotransmitters are reabsorbed by the presynaptic neuron after signaling, regulating neurotransmitter levels.

Norepinephrine

Involved in arousal, alertness, and the fight-or-flight response.

Glutamate

The main excitatory neurotransmitter in the brain, playing a key role in learning and memory.

GABA

Gamma-aminobutyric acid, the primary inhibitory neurotransmitter in the brain, helping to regulate neuronal excitability.

Endorphins

Neuropeptides that act as natural painkillers and mood enhancers, often released during exercise.

Substance P

A neuropeptide involved in the transmission of pain and the regulation of emotions.

Acetylcholine

A neurotransmitter that plays a key role in muscle contraction and cognitive functions.

Adrenaline

A hormone and neurotransmitter that increases heart rate and energy availability during stress.

Leptin

A hormone produced by adipose tissue that helps to regulate body weight by inhibiting hunger.

Ghrelin

A hormone that stimulates appetite and plays a role in energy balance.

Melatonin

A hormone that regulates sleep-wake cycles, produced in response to darkness.

Oxytocin

A hormone associated with bonding, social interactions, and reproductive behaviors.

Psychoactive Drugs

Substances that alter perception, mood, and cognitive functions.

Agonist

A substance that binds to a receptor and activates it, mimicking the action of a natural neurotransmitter.

Antagonist

A substance that binds to a receptor but does not activate it, blocking the action of agonists.

Reuptake Inhibitor

A drug that prevents the reabsorption of neurotransmitters, increasing their availability in the synaptic cleft.

Stimulant

Substances that increase activity in the central nervous system; examples include caffeine and cocaine.

Caffeine

A common stimulant found in coffee and tea, known to enhance alertness and reduce fatigue.

Cocaine

A powerful stimulant drug that increases dopamine levels in the brain, leading to heightened energy and euphoria.

Depressant

Substances that decrease activity in the central nervous system; alcohol is a well-known example.

Alcohol

A depressant that affects mood, cognition, and motor skills by slowing brain function.

Hallucinogen

Substances that alter perception, mood, and thought; marijuana is a common example.

Marijuana

A hallucinogenic drug derived from the cannabis plant, known for its psychoactive effects.

Opioid

A class of drugs that include both legal and illegal substances, known for their pain-relieving properties.

Heroin

An illegal opioid drug that produces intense euphoria and is highly addictive.

Tolerance

A state where increased doses of a drug are needed to achieve the same effect due to repeated use.

Addiction

A chronic condition characterized by compulsive drug seeking and use, despite harmful consequences.

Withdrawal

Refers to the symptoms that occur when a dependent individual reduces or stops drug use.

Brainstem

The part of the brain responsible for regulating vital functions, such as breathing and heart rate.

Medulla

A part of the brainstem that controls autonomic functions like heart rate and breathing.

Reticular Activating System

A network of neurons in the brain stem that regulates wakefulness and sleep-wake transitions.

Cerebellum

A region of the brain that coordinates voluntary movements and maintains posture and balance.

Cerebral Cortex

The outer layer of the brain, involved in high-level functions such as thought, perception, and decision-making.

Left and Right Hemisphere

The brain is divided into two hemispheres, each responsible for different functions; one hemisphere is associated with language and analytical tasks, while the other is linked to creativity and spatial abilities.

Thalamus

Acts as the brain's relay station, transmitting sensory information to the appropriate areas of the cerebral cortex.

Hypothalamus

A small brain region that regulates key functions such as temperature, hunger, thirst, and the sleep-wake cycle.

Pituitary Gland

The 'master gland,' which controls various hormonal functions and regulates other endocrine glands.

Hippocampus

A critical region for memory formation and spatial navigation.

Amygdala

Involved in emotions and memory processing, particularly fear and pleasure.

Corpus Callosum

A band of nerve fibers that connects the left and right hemispheres, facilitating communication between them.

Occipital Lobe

The rearmost part of the brain and is primarily responsible for processing visual information.

Parietal Lobe

Processes sensory information related to touch, temperature, and pain while integrating visual information.

Temporal Lobe

Involved in processing auditory information and is also important for memory and language.

Frontal Lobe

Responsible for higher cognitive functions such as thinking, planning, and impulse control.

Somatosensory Cortex

Processes sensory input from the body, including touch, pain, and temperature signals.

Prefrontal Cortex

Involved in complex behaviors such as decision-making, social interactions, and personality.

Motor Cortex

Responsible for planning and executing voluntary movements.

Split-Brain Research

Studies individuals who have undergone corpus callosum severance, helping understand the specialization of each hemisphere.

Broca's Area

Located in the frontal lobe and is crucial for language production and speech.

Wernicke's Area

Located in the temporal lobe and is essential for language comprehension.

Contralateral Organization

Refers to the brain's principle that the left hemisphere controls the right side of the body and vice versa.

Aphasia

A language disorder resulting from brain damage, affecting the ability to communicate verbally or understand language.

Brain Plasticity

Or neuroplasticity, is the brain's ability to adapt and change in response to experience, learning, and injury.

EEG (Electroencephalography)

A technique that records electrical activity of the brain using sensors placed on the scalp.

fMRI (Functional Magnetic Resonance Imaging)

A brain imaging technique that measures and maps brain activity by detecting changes in blood flow.

Lesioning

Involves deliberately damaging specific brain areas to study their functions and effects on behavior.

Mirror Neuron

Specialized cells that activate when an individual performs an action and when they observe the same action performed by others.

Pons

Part of the brainstem that connects the upper and lower parts of the brain and plays a role in regulating sleep and arousal.

Synapse

The junction between two neurons, allowing for the transmission of information via neurotransmitters.

Dendrites

Tree-like structures on neurons that receive signals from other neurons.

Axon

The long, slender projection of a neuron that transmits electrical impulses away from the cell body.

Axon Terminal

The endpoints of an axon that release neurotransmitters to communicate with other neurons.

Terminal Buttons

Small knobs at the end of axon terminals that contain neurotransmitter vesicles.

Myelin Sheath

A fatty layer that surrounds axons, facilitating faster nerve impulse transmission.