Glossary 2 Flashcards
Dyslexia
A pronounced difficulty with read¬ing despite normal intelligence, education, and motivation.
Endorphins
Neurotransmitters produced in the brain that generate cellular and behavioral effects like those of morphine.
Epilepsy
A disorder characterized by repeated seizures, which are caused by abnormal exci¬tation of large groups of neurons in various brain regions. Epilepsy can be treated with many types of anticonvulsant medications.
Epinephrine
A hormone released by the adrenal medulla and specialized sites in the brain. During times of stress, epinephrine, also known as adrenaline, is quickly released into the bloodstream. It then serves to put the body into a general state of arousal, which enables it to cope with the challenge.
Episodic Memory
A type of declarative memory consisting primarily of memory of personal experiences.
Estrogen
A female sex hormone produced primarily in the ovaries.
Excitation
A change in the electrical state of a neuron that is associated with an enhanced probability of action potentials.
Excitatory
A type of neuron (or neurotrans¬mitter) that excites target neurons and increases the likelihood of their firing an action potential.
Executive Function
Higher-level processing that takes place in the brain’s prefrontal cortex. Executive function comprises impulse control, working memory, and mental flexibility.
Forebrain
A region of the developing brain that goes on to become the cerebral hemi¬spheres and major parts of the limbic system.
Fovea
A small, pitted area in the center of the retina where visual acuity is highest, due to a high density of cones.
Fragile X Syndrome
A genetic condition resulting from a mutation in the FMR1 gene that causes intellectual disability.
Frontal Lobe
One of the four subdivisions of the cerebral cortex. The frontal lobe has a role in controlling movement and in the planning and coordinating of behavior.
Functional Magnetic Resonance Imaging (fMRI)
A technology that uses magnetic fields to detect activity in the brain by monitoring blood flow.
Gamma-Aminobutyric Acid (GABA)
An amino acid neurotransmitter in the brain whose primary function is to inhibit the firing of nerve cells.
Glia
Specialized cells that nourish and support neurons.
Glucocorticoid Hormones
Hormones that produce an array of effects in response to stress. Some of the actions of glucocorti¬coids help to mediate the stress response, while other, slower actions counteract the primary response to stress and help to re-establish homeostasis.
Glutamate
An amino acid neurotransmit¬ter that acts to excite neurons. Glutamate stimulates N-methyl-d-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methylisox¬azole-4-propionic acid (AMPA). AMPA receptors have been implicated in activities ranging from learning and memory to devel¬opment and specification of nerve contacts in developing animals. Stimulation of NMDA receptors may promote beneficial changes, whereas overstimulation may be a cause of nerve cell damage or death in neurological trauma and stroke.
Gray Matter
Portions of the brain that are gray in color because they are composed mainly of neural cell bodies, rather than myelinated nerve fibers, which are white. It includes the cerebral cortex as well as s ubcortical structures.
Growth Cone
A distinctive structure at the growing end of most axons. It is the site where new material is added to the axon.
Hair Cells
Sensory receptors in the cochlea that convert mechanical vibrations to elec¬trical signals; they in turn excite the 30,000 fibers of the auditory nerve that carry the signals to the brainstem.
Hindbrain
The most posterior part of the brain, comprising the pons, medulla, and cerebellum.
Hippocampus
A seahorse-shaped structure located within the brain and considered an important part of the limbic system. One of the most studied areas of the brain, it is involved in learning, memory, and emotion.
Histamine
A compound with multiple func¬tions in the body. In the brain, histamine acts as a neurotransmitter to stimulate arousal. Lo¬cal inflammatory responses in the body trigger the release of histamines from immune cells.
Homeostasis
The normal equilibrium of body function.
Hormones
Chemical messengers secreted by endocrine glands to regulate the activity of target cells. They play a role in sexual develop¬ment, calcium and bone metabolism, growth, and many other activities.
Huntington’s Disease
A genetic disorder characterized by involuntary jerking move¬ments of the limbs, torso, and facial mus¬cles, often accompanied by mood swings, depression, irritability, slurred speech, and clumsiness.
Hyperpolarization
A change in a neuron’s membrane potential in which the cytoplasm becomes more negatively charged and there¬fore less likely to fire an action potential.
Inhibition
A change in the electrical state of a neuron that is associated with a decreased probability of firing an action potential.
Inhibitory
A type of neuron (or neurotrans¬mitter) that prevents a target neuron from firing.
Insomnia
A sleep disorder in which people have trouble falling and/or staying asleep.
Interneuron
A neuron that exclusively signals another neuron.
Involuntary Movement
A movement that occurs without conscious control, such as a reflex.
Ion Channel
Proteins embedded in the cell membrane that allow ions or other small molecules to enter or leave the cell.
Limbic System
A group of structures deep within the brain involved in motivation and emotion. The hippocampus, amygdala, thal¬amus, and hypothalamus are all a part of the limbic system.
Long-Term Memory
The final phase of memory, in which information storage may last from hours to a lifetime.
Long-Term Potentiation (LTP)
A long-lasting increase in synaptic strength resulting from an increased number of neurotransmitter recep¬tors on the post-synaptic neuron.
Magnetic Resonance Imaging (MRI)
A technique that uses magnetic fields to create a high-quality, three-dimensional image of organs and structures inside the body. This technology is noninvasive and does not expose the body to X-rays or other radiation.
Magnetoencephalography (MEG)
A technique that can quantitatively measure the strength of activity in various regions of the brain at millisecond resolution.
Medulla
Also called the medulla oblongata, a structure of the brainstem that controls basic functions like swallowing, breathing, and heart rate.
Melatonin
A hormone produced in the pine¬al gland that regulates responses to light-dark cycles and induces sleep at night.
Membrane Potential
The voltage difference between the inside and outside of a neuron. The typical membrane potential of a neuron at rest is -70mV.
Mentalization
The ability to understand the mental states and thoughts of others and oneself.
Microglia
Glial cells in the central nervous system that function as resident immune cells.
Midbrain
The most anterior segment of the brainstem. With the pons and medulla, the midbrain is involved in many functions, including regulation of heart rate, respiration, pain perception, and movement.
Migration
The process whereby new neurons find their proper position in the brain.
Mitochondria
Small cylindrical organelles inside cells that provide energy for the cell by converting sugar and oxygen into special energy molecules, called adenosine triphosphate (ATP).
Mood
A general state of mind and emotional disposition.
Motor Cortex
A specialized region in the cortex involved in the planning and execution of movement.
Motor Neuron
A neuron that carries information from the central nervous system to muscles.
