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Amygdala – an area of the brain beneath the cerebral cortex near the underside of the brain. It is involved in mood and emotions. A dysfunctional amygdala results in anxiety and moodiness.

Apoptosis – a genetically-programmed form of cell death — ‘cell death by suicide;’ during development those neurons that don’t grow properly self- destruct.

Attention Deficit Disorder (ADD) – a neurologically-based condition in which the individual has significant impairment in academic, social, or occupational functioning due to symptoms of inattention and impulsivity. If hyperactivity is present, the disorder is called ADHD.

Axon – a long appendage leaving the neuron cell body that ends in a terminal. Electrical impulses flow from the cell body down the axon to the terminal where neurotransmitters are released.

Basal Ganglia – a set of structures beneath the cerebral cortex, in the middle of the brain, that includes the caudate nucleus. These structures govern movement, cognition, executive functioning, and mood.

Caudate Nucleus – a structure beneath the cerebral cortex that controls movement, cognition, and executive function.

Corpus Callosum – a set of nerve bundles that connect the right and left hemispheres of the brain. These myelinated nerve fibers help govern cognition, motor function, verbal learning, and executive function. Prenatal alcohol exposure can prevent the corpus callosum from developing.

Cerebellum – a structure that lies above the brainstem; it governs balance and coordination, and it plays a role in cognition, language fluency, and perception of time.

Cerebral Cortex – the largest part of the brain; it is highly developed, consisting of 4 lobes that govern thinking, reasoning, movement, touch, vision, hearing, and smell. Specific areas within the cerebral cortex are responsible for speech and language, attention, judgment, impulsivity, abstract thought, and working memory.

Cognition – the psychological result of perception, learning, and reasoning.

Dendrites – a branching-like part of the neuron that contains numerous synapses for receiving information from other neurons. Information flows from the dendrite toward the cell body.

Dendritic Spines – small protrusions on dendrites; these contain the synapses for receiving information from a neighboring neuron. Prenatal alcohol exposure decreases the density of spines on dendrites.

Dopamine – a neurotransmitter that is important in motor function, mood, judgment, executive functioning, and attention.

Executive Function – a cluster of processes involved in the ability to plan and guide behavior to achieve a goal in an efficient manner.

γ-Aminobutyric acid (GABA) – a neurotransmitter that is important in learning and memory, anxiety, and sleep.

Glial Cells – a major cell-type in the brain that provides support and clears away debris; during development, it provides a scaffold to help neurons migrate to the places they need to be.

Glutamate – a neurotransmitter that is important in learning and memory.

Habituation – the ability of an organism to “tune out” the many stimuli confronting it that are not relevant to its well-being.

Hippocampus – a curved structure that lies deep in the heart of the brain; it is very important in learning and memory.

Individual Education Plan (IEP) – the specific educational plan and strategies designed for a student who qualifies for special education services under PL 94-142 (IDEA).

Least Restrictive Environment – from PL 94-142 (IDEA) requiring that, to the greatest extent possible, students with disabilities must be educated with their non-disabled peers.

Magnetic Resonance Imaging (MRI) – an imaging technique that uses electromagnetic forces to detect the structures deep inside the body. It has excellent resolution, providing detailed 3D information about brain structures.

Mainstreaming – placing students with special needs in regular education classes with accommodations and modification support services.

Metapragmatics – that part of language that is a tool for social interaction and negotiation.

Microcephaly – a small head circumference. Although many FASD children have microcephaly, some may have a normal head circumference.

Myelin – a fatty sheath that surrounds long axons. This sheath helps the nerve conduct electrical impulses down the axon to the terminal.

Neurons – a major cell-type in the brain that provides intracellular communication using electrical and chemical signals.

Neurotransmitters – a chemical that is stored in axon terminals and released upon an electrical stimulus. The neurotransmitter binds to specific receptors on neighboring neurons to produce a change in neuron firing rates or in enzyme function. Before birth, neurotransmitters function as neuronal growth factors.

Norepinephrine – a neurotransmitter involved in mood, anxiety, control of respiratory, and cardiovascular function.

Orbitofrontal Cortex – an area of the cerebral cortex at the base of the frontal lobe. It is important in judgment and impulsiveness.

Organogenesis – the formation of organs. This takes place early during the 1st trimester.

Palpebral Fissure – the space between the upper and lower eyelid; the width is shortened in children with FAS.

Parietal Cortex – an area of the cerebral cortex that governs attention, working memory, abstract thought, and sensations.

Philtrum – the groove between the bottom of the nose and the top of the upper lip; it is flattened in children with FAS.

Positron Emission Tomography – an imaging technique that uses radioactive molecules to indicate how specific brain structures are functioning (for example, utilization of glucose).

Prefrontal Cortex – an area of the cerebral cortex in the frontal lobe that helps to regulate executive functioning and judgment.

Receptors– specialized proteins that bind to neurotransmitters and hormones; the binding initiates some form of cellular work.

Serotonin – a neurotransmitter involved in regulating mood, anxiety, and visual perception.

Spines – see ‘dendritic spines.’

Synapse – the connection between two neurons; it includes the terminal of one axon, the membrane of a neighboring neuron (usually a dendrite), and the space between. It is where the neurotransmitter is released and most of the receptors are found. The synapse is where neurotransmission takes place.

Synaptogenesis – the formation of synapses. This takes place in the 2nd and 3rd trimesters once neurons have migrated to the place where they need to be. It also continues through adolescence!