Neuroscience: The Biological Perspective — Vocabulary Flashcards
LO 2.1 Parts of nervous system
Nervous system: an extensive network of specialized cells that carry information to and from all parts of the body.
Neuroscience: studies the structure and function of neurons, nerves, and nervous tissue; relates directly to behavior and learning.
Central nervous system (CNS): brain and spinal cord.
Peripheral nervous system (PNS): all nerves and neurons outside the CNS; transmits information to and from the CNS.
Autonomic nervous system (ANS): automatically regulates glands, internal organs, blood vessels, pupil dilation, digestion, and blood pressure.
Somatic nervous system: carries sensory information to the CNS and controls the movement of skeletal muscles.
Functional divisions within ANS:
Parasympathetic division: maintains body functions under ordinary conditions; saves energy.
Sympathetic division: prepares the body to react and expend energy in times of stress.
Practical implications: these divisions coordinate to balance energy use, reflexes, and responses to the environment.
LO 2.2 Neurons and nerves
Neurons: the basic cells of the nervous system; receive and send messages within the system.
Parts of a neuron:
Dendrites: branch-like structures that receive messages from other neurons.
Soma (cell body): maintains cell life.
Axon: long tube-like structure that carries neural messages to other cells.
Node (Nodes of Ranvier): gaps along the axon that facilitate rapid conduction.
Synaptic knobs (terminal buttons): endings of axons where neurotransmitters are released.
Synaptic vesicles: sacs inside synaptic knobs containing neurotransmitters.
Myelin: fatty insulation around many axons, produced by glial cells; speeds neural impulses.
Glial cells: support neurons, provide nutrients, produce myelin, clean up waste and dead neurons.
Neurons in the body: Nerves are bundles of axons traveling together through the body.
Neurilemma (Schwann’s membrane): membrane surrounding a nerve fiber in the PNS; provides a tunnel for repair after injury.
LO 2.3 Neuron communication
Neurons must be turned ON (fired) and OFF (not fired).
Action potential: the neural impulse; a rapid reversal of electrical charge across the axon membrane.
Resting potential: neuron is negatively charged inside, positively charged outside.
Triggered by the influx of positive ions (sodium, Na+) when threshold is reached.
All-or-none principle: a neuron fires completely or not at all.
Return to resting potential after firing via pumping of ions to restore original charge.
Excitatory vs inhibitory neurotransmission:
Excitatory neurotransmitter: causes the receiving cell to fire.
Inhibitory neurotransmitter: causes the receiving cell to stop firing.
Chemical signaling can be modulated by agonists (mimic/enhance transmitters) and antagonists (block/reduce transmitter effects).
LO 2.4 Neurotransmitters
Overview: chemical messengers found in synaptic vesicles that influence the next cell when released.
Major neurotransmitters and functions:
Acetylcholine: involved in memory and stimulates movement.
Serotonin: involved in mood, sleep, and appetite.
GABA (Gamma-aminobutyric acid): involved in sleep and inhibits movement.
Glutamate: involved in memory formation.
Norepinephrine: involved in arousal and mood.
Dopamine: involved in control of movement and sensations of pleasure.
Endorphins: involved in pain relief.
Note: receptor sites on the postsynaptic neuron are shaped to fit specific neurotransmitters.
LO 2.5 Brain and spinal cord
Central nervous system (CNS): brain and spinal cord.
Spinal cord: a long bundle of neurons that carries messages to and from the body to the brain and is responsible for very fast, lifesaving reflexes (reflex arcs).
The Reflex Arc: involves sensory (afferent) neurons, interneurons in the spinal cord, and motor (efferent) neurons; a quick, automatic response to a stimulus.
LO 2.6 Somatic nervous system
Somatic nervous system (SNS): division of the PNS consisting of nerves that carry information from senses to the CNS and from the CNS to the voluntary muscles.
Sensory pathway (afferent): nerves coming from sensory organs to the CNS, comprised of sensory neurons.
Motor pathway (efferent): nerves coming from the CNS to voluntary muscles, comprised of motor neurons.
LO 2.7 Autonomic nervous system
Autonomic nervous system (ANS): division of the PNS that controls involuntary muscles, organs, and glands.
Sympathetic division (fight-or-flight): prepares the body to react to stress and increases arousal.
Parasympathetic division: restores the body to normal functioning after arousal and supports day-to-day organ/gland functioning.
Practical implication: ANS coordinates physiological states (e.g., heart rate, digestion) in response to internal and external cues.
LO 2.8 Study of the brain
Clinical and research methods to study brain function:
Deep lesioning: insertion of a thin wire to destroy brain cells at the tip; used to study function by removing a brain area.
Electrical stimulation of the brain (ESB): milder current that causes neurons to react as if they had received a message.
Electroencephalograph (EEG): records brain wave patterns from the brain's surface.
Computed tomography (CT): X-ray brain imaging.
Positron emission tomography (PET): uses radioactive sugar to visualize brain activity.
Magnetic resonance imaging (MRI): uses magnetic fields and radio waves for detailed brain images.
Functional MRI (fMRI): creates a movie-like sequence showing brain activity over time.
LO 2.9 Structures of the bottom part of the brain (brainstem and cerebellum)
Medulla: the lower part of the brainstem; life-sustaining functions (breathing, swallowing, heart rate).
Pons: connects upper and lower brain areas; involved in sleep, dreaming, left-right coordination, and arousal.
Reticular formation (RF): neurons through the medulla and pons; regulates selective attention.
Cerebellum: coordinates involuntary, rapid, fine motor movements; balance and coordination.
LO 2.10 Structures controlling emotion, learning, memory, and motivation
Limbic system: a group of structures under the cortex involved in learning, emotion, memory, and motivation.
Thalamus: central relay station; relays sensory information to the cortex and processes some information before sending it.
Olfactory bulbs: process smell information.
Hypothalamus: below the thalamus; regulates motivated behaviors (sleep, hunger, thirst, sex); controls pituitary gland (master endocrine gland).
Pituitary gland: master endocrine gland; regulates other hormone-secreting glands.
Hippocampus: essential for forming long-term memories and memory for location of objects.
Amygdala: fear responses and memory of fear; involved in emotional processing.
LO 2.11 Parts of cortex controlling senses and movement
Cortex: outermost covering of the brain; responsible for higher thought processes and interpretation of sensory input.
Corticalization: wrinkling of the cortex; increases cortical surface area.
Cerebral hemispheres: left and right halves of the cortex; connected by the corpus callosum.
Corpus callosum: thick band of neurons connecting left and right hemispheres.
Four lobes and their primary roles:
Occipital lobe: visual centers; primary visual cortex processes visual input; visual association cortex interprets visual information.
Parietal lobes: touch, taste, temperature; somatosensory cortex runs down the front of the parietal lobes and processes touch, temperature, body position, and possibly taste.
Temporal lobes: hearing and meaningful speech; primary auditory cortex processes auditory input; auditory association cortex interprets sounds.
Frontal lobes: higher mental processes, decision making, production of fluent speech; motor cortex at the back of the frontal lobe sends motor commands to skeletal muscles.
LO 2.12 Parts of cortex responsible for higher thought
Association areas: coordinate and interpret information; enable higher mental processing.
Broca’s aphasia: damage to Broca’s area (usually left frontal lobe) causes non-fluent speech, halting, mispronounced words.
Wernicke’s aphasia: damage to Wernicke’s area (usually left temporal lobe) causes difficulty understanding or producing meaningful language.
Spatial neglect: damage to association areas of the right hemisphere leading to inattention to the left visual field.
Key anatomists/regions mentioned: Broca’s area, Wernicke’s area, angular gyrus, visual areas, and their contributions to language and perception.
LO 2.13 Left side and right side of the brain
Split-brain research isolates messages to one hemisphere to reveal specialization.
Visual pathways in split-brain: left visual field → right hemisphere; right visual field → left hemisphere via the optic chiasm and corpus callosum.
Classic Sperry experiment: participants viewed composite faces; language-dominant left hemisphere processed one aspect, while the right hemisphere processed another.
Language is primarily a left-hemisphere function for most individuals; right hemisphere handles nonverbal processing (emotion, spatial tasks, pattern recognition).
Output differences in split-brain: verbal responses typically from left hemisphere; some nonverbal responses (e.g., pointing with left hand) from right hemisphere.
LO 2.14 Hormones interact with nervous system and affect behavior
Endocrine glands: glands that secrete hormones directly into the bloodstream.
Hormones: chemicals released into the bloodstream by endocrine glands.
Pituitary gland: located in the brain; secretes human growth hormone and influences all other hormone-secreting glands; known as the master gland.
Pineal gland: secretes melatonin.
Thyroid gland: regulates metabolism.
Pancreas: regulates blood glucose levels.
Gonads: sex glands regulate sexual development, behavior, and reproduction; ovaries (female) and testes (male).
Adrenal glands: atop each kidney; secrete over 30 hormones to deal with stress, regulate salt intake, and provide secondary sex hormones affecting adolescence.
Connection to the nervous system: the endocrine system and the nervous system interact to regulate behavior through hormones and neural signaling.
Figures and Key Concepts (referenced in text)
Fig. 2.1: Overview of the nervous system showing CNS (brain, spinal cord) and PNS (nerves), plus subdivisions (parasympathetic, sympathetic).
Fig. 2.2: Structure of a neuron (dendrites, soma, axon, myelin, axon terminals, synapses).
Fig. 2.3: Neural impulse and action potential; resting potential (-70 mV), threshold (-50 mV), peak (+40 mV); movement of Na+ ions; all-or-none response; refractory period.
Fig. 2.4: The synapse and neurotransmitter communication across the synaptic gap to receptor sites.
Fig. 2.5: Spinal cord reflex diagram showing afferent, interneuron, and efferent pathways.
Fig. 2.7 & 2.8: Peripheral nervous system and parasympathetic vs sympathetic functions.
Fig. 2.10–2.11: Lobes, cortical areas (motor cortex, somatosensory cortex), and the somatotopic organization of the body in the cortex.
Fig. 2.11–2.12: Broca’s/Wernicke’s areas and association areas; Broca’s aphasia and Wernicke’s aphasia.
Fig. 2.14–2.15: Endocrine glands and their locations; pituitary as master gland and major hormones.
Quick reference: key numerical values and terms (LaTeX)
Resting potential: -70 ext{ mV}
Threshold: -50 ext{ mV}
Action potential peak: +40 ext{ mV}
Time window for measuring neural impulse in classic graphs: 20-30 ext{ ms}
Primary neurotransmitter categories: Acetylcholine, Serotonin, GABA, Glutamate, Norepinephrine, Dopamine, Endorphins
Key brain regions: Medulla, Pons, Reticular Formation (RF), Cerebellum, Thalamus, Hypothalamus, Hippocampus, Amygdala, Olfactory Bulbs, Pituitary, Pineal, Thalamus, Cerebral Cortex, Corpus Callosum
Primary lobes: Occipital, Parietal, Temporal, Frontal
Major sensory/motor areas: Primary Visual Cortex, Visual Association Cortex, Primary Auditory Cortex, Auditory Association Cortex, Somatosensory Cortex, Motor Cortex
Split-brain concept: separation of left/right hemispheric processing; language vs nonverbal processing differences
Endocrine glands listed: Pituitary, Pineal, Thyroid, Pancreas, Gonads (Ovaries, Testes), Adrenal Glands
This set of notes provides a comprehensive, organized overview of the material from Chapter 2: Neuroscience — The Biological Perspective, aligned with the LO 2.x objectives and including the major and minor points, processes, and implications discussed in the transcript.