Ch.1 An Invitation to Neurobiology Flashcards
Nature
The contribution of genetic inheritance to brain function and behavior
Nurture
The contribution of environmental factors to brain function and behavior
Monozygotic (identical) twins
Twins produced from the same fertilized egg or zygote, they share 100% of their genomes
Dizygotic twins
Non-identical (fraternal) twins who share only 50% of their genes, because they originated from two independent eggs fertilized by two independent sperm
Heritability
A measure of the contribution of genetic differences to to trait differences within a population
Epigenetic modifications
Molecular modifications to DNA and chromatin, such as DNA methylation and various forms of post-translational modifications of histones. They do not modify the DNA sequence but can alter gene expression
Innate
A trait or behavior that is genetically programmed and that is thus with an organism from birth rather than acquired by experience
Stereotypy
A trait or behavior that is largely invariant in different individual organisms
Neuroethology
A branch of science that emphasizes the study of animal behavior in the natural environment
Fixed action pattern
An instinctive sequence of behaviors, it is largely invariant and runs to completion once triggered
Releasers
The essential features of a stimulus that activate a fixed action pattern
Neural plasticity
Changes of the nervous system in response to experience and learning
Central Nervous System (CNS)
The brain and spinal cord in vertebrates; the brain and nerve cord in some invertebrates
Brain
The rostral part of the CNS located in the head. It is the command center for nervous system functions
Spinal Cord
The caudal part of the vertebrate CNS enclosed by the vertebral column
Hemispheres
The two sides of the brain
Cerebral Cortex
The outer layer of the neural tissue in the rostral part of the mammalian brain. It is associated with higher functions including sensory perception, cognition, and control of voluntary movement
Basal Ganglia
A collection of nuclei underneath the cerebral cortex, it includes the straitum, globus pallidus, subthalmic nucleus, and substantia nigra and is essential for motor initiation and control, habit formation, and reward-based learning
Hippocampus
A structure underneath the cortical surface of the temporal lobe. It has been most studied for its role in the acquisition of explicit memory and representation of space
Amygdala
An almond-shaped structure underneath the temporal lobe best known for its role in processing emotion-related information
Thalamus
A structure situated between the cerebral cortex and the midbrain, it relays sensory and motor signals to the cerebral cortex through its extensive bidirectional connections with cortex
Hypothalamus
A collection of nuclei ventral to the thalamus, it controls many bodily functions including eating, digesting, metabolic rate, drinking, salt intake, reproduction, body temperature, emergency response, and circadian rhythms. It executes many of these functions by regulating the autonomic nervous system and neuroendocrine system
Cerebellum
A structure located dorsal to the pons and medulla, it plays an important role in motor coordination, motor learning, and cognitive functions
Midbrain
The rostral-most part of the brainstem, it includes the tectum (superior and inferior colliculus in mammals) dorsally and the tegmentum ventrally. Ot is also the middle part of the three divisions of the embryonic brain caudal to the forebrain and rostral to the hindbrain. It is also called the mesencephalon
Pons
The middle part of the brainstem caudal to the midbrain and rostral to the medulla
Medulla
The caudal-most part of the brainstem between the pons and the spinal cord
Forebrain
The rostral-most division of the three divisions of the embryonic brain. It gives rise to the cerebral cortex, basal ganglia, hippocampus, amygdala, thalamus, and hypothalamus
Hindbrain
The caudal-most division of the three divisions of the embryonic brain. It gives rise to the pons, medulla, and cerebellum
Nerve
A discrete bundle of axons in the peripheral nervous system
Ganglia
A cluster of neurons located in the peripheral nervous system
Coronal section
A section plane that is perpendicular to the rostral-caudal axis; also called frontal or transverse sections
Sagittal section
A section plane that is perpendicular to the medial-lateral axis
Medial-lateral
Of a body axis, from midline to side
Horizontal sections
A section plane that is perpendicular to the dorsal-ventral axis
Dorsal-ventral
Of a body axis, from back to belly
Neuraxis
Axis of the CNS. The rostral-caudal neuraxis follows the curvature of the embryonic neural tube; the dorsal-ventral neuraxis is perpendicular to the rostral-caudal neuraxis
Neural tube
A hollow tube surrounded by layers of neuroectodermal cells, it is the embryonic precursor to the vertabrate CNS
Glia
Nonneuronal cells of the nervous system, they play essential roles for the development and function of neurons
Neuronal process
Cytoplasmic extension of a neuron
Axon
A long, thin process of a neuron, it often extends far beyond the soma and propagates and transmits signals to other neurons or muscle at its presynaptic terminals
Soma
Cell body of a neuron or any cell
Dendrites
Thick, bushy processes of a neuron that receive and integrate synaptic inputs from other neurons
Presynaptic terminal
A structure at the end (or along the trunk) of an axon that is specialized for releasing neurotransmitters onto target cells
Dendritic spine
A small protrusion on a dendrite of certain neurons that receives synaptic input from a partner neuron. The thin spine neck creates chemical and electrical compartments for each spine such that it can be modulated independently from neighboring spines
Oligodendrocyte
A glial cell in the CNS that wraps axons with its cytoplasmic extension to form myelin sheath
Schwann cell
A glial cell in the PNS that wraps axons with its cytoplasmic extension to form myelin sheath
Astrocyte
A glial cell present in the gray matter. It plays many roles including synaptic development and function
Microglia
A glial cell that functions as the resident immune cell of the nervous system. It engulfs damaged cells and debris
Myelin sheath
Cytoplasmic extensions of oligodendrocytes and Schwann cells, they wrap around axons with multi-layered glial plasma membrane to increase resistance and decrease capacitance for action potential propagation
White matter
The parts of the CNS that are enriched with oligodendrocytes and myelinated axons and that appear white because of the high lipid content of the myelin
Gray matter
The parts of the CNS that are enriched with neuronal cell bodies, dendrites, axon terminals, and synapses and that appear gray
Cell theory
The idea that all living organisms are composed of cells as basic units
Reticular theory
The idea that the processes of nerve cells fuse and form a giant net that constitutes the working unit of the nervous system. It has been mostly disproven (with the exception of electrical synapses, that allow limited exchange of ions and small molecules between partner neurons)
Golgi staining
A histological staining method, it uses solutions of silver nitrate and potassium dichromate, which react to form a black precipitate (microcrystals of silver chromate). This precipitate accumulates stochastically in a small fraction of the nerve cells so that these cells, and most or all of their elaborate extensions, can be visualized against unstained tissue
