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- Macro Cisterna Magna
- a space in the posterior fossa that receives CSF from the foramen of Magendie and Luschka; a cerebellomedullary cistern that is a normal anatomical variant, but may be a marker for brain maldevelopment
- Macrocephaly
- "large head" - ventricles are slightly enlarged or normal
- What disorders are associated with macrocephaly?
- late stages of Tay-Sachs disease, Alexander disease, and spongy degeneration of infancy
- Macropsia
- a type of visual illusion in which objects appear to move closer or become larger
- Macropsia may be a symptom of what type of disorder?
- macropsia is cometimes a symptom of partial seizures
- Magnetic Resonance Angiography (MRA)
- noninvasive MR technique that allows one to visualize the cerebral vasculature; sensitive to stenosis/occlusion of carotid arteries
- Magnetic Resonance Imaging (MRI)
- imaging procedure that uses magnetic fields and radio frquency pulses to excite protons such that they emit electromagnetic signals
- What is the difference between T1 and T2 MRI images?
-
T1 - white matter is brighter than gray
T2 - CSF is brigther than gray matter - Magnetic Resonance Spectroscopy (MRS)
- noninvasive technique used to measure chemical makeup of tissue
- Magnetoencephalography (MEG)
- technique similar to EEG that allows one to examine dipole sources in 3-D
- Malignant
- progressive or fatal
- Malingering
- feigning or exaggeration of medical/psychological symptoms from illness or injury for secondary gain
- How does malingering differ from samatoform disorders?
- somatoform disorders result from an attempt to mannipulate others (gain attention) or from psychological factors (avoid emotional conflict)
- Mammillary bodies
- two oval shapped structures located on the basal surface of the posterior hypothalamus
- What disorder results from damage to the mammillary bodies?
- Korsakoff's syndrome - patients develop amnesia due to thiamine deficiency from prolonged alcohol use
- One of the major neocortical neural pathways goes through the mammillary bodies? Describe the trajectory of this pathway.
- hippocampus -- mammillary bodies (via postcommissural fibers of fornix) -- anterior nucleus of thalamus (via mammillothalamic tract) -- anterior cingulate gyrus
- Mania
- abnormally expansive mood -- may include irritability, increased motor movement, flight of ideas, elation, reduced sleep, and pressured speech
- March A Petis Pas
- festinating gait (as in Parkinson's disease)
- Marchiafava-Bignami Disease
- progressive degeneration of the corpus callosum often accompanied by emotional disturbance, hallucinations, confusion, seizures, tremor, rigidity, and cognitive decline; rapid progression of symptoms leads to dementia, coma, and then death (often in only a few months)
- What individuals are most likekly to develop Marchiafava-Bignami Disease?
- middle-age alcoholics (especially those who drink excessive amounts of red wine)
- Marching Test
- a subtest from the Halstead-Reitan Battery for children that assesses gross motor function; child must connect circles that are already connected by lines
- Marcus Gunn Pupil
- pupil dilates when subjected to light - result of damage to 2nd cranial nerve (optic); often seen in MS
- Masked Facies
- flat affect often observed in patients with Parkinson's disease (aka "reptilian stare")
- Masking
- perception of one stimulus is partially or completely suppressed due to presentation of a second stimulus; aka extinction - may be part of neglect syndrome
- What is the difference between forward and backward masking?
-
Forward masking - masking stimulus is presented before target stimulus
Backward masking - masking stimulus is presented after the target stimulus - Mass Action
- Lashley's theory that the entire cortex is involved in learning (related to equipotentiality)
- Mass Effect
- increased intracerebral volume results in increased intracranial volume causing impairment of brain function (often occurs with tumor, stroke, or other brain injury)
- Massa Intermedia
- an mass of gray matter fromed by interhalamic connections that crosse the third ventricle; not present in all human brains; appears functionless
- Material-Specific Learning
- left hemisphere specialization for verbal learning and right hemsiphere specialization for nonverbal learning
- Matrix Reasoning
- WAIS-III subtest that assesses pattern completion and reasoning
- Mattis Dementia Rating Scale (DRS)
- a dementia screening measure; assesses 5 cognitive domains -attention, construction, initiation/perseveration, coconceptualization, and memory
- Mayo Older Age Normative Study (MOANS)
- normative data for a number of neuropsychological measures for individuals aged 55-97
- Mazes
- visual planning measure that requires patient to trace maze route without running into dead ends (e.g. Porteus Mazes)
- McCarthy Scales of Children's Abilities
- measure of cognitive and motor functioning designed for children aged 2.5 to 8.5; 18 subtests yield 5 index scores: verbal, perceptual-perforamnce, quantitative, memory, and motor
- Mean
- average of multiple scores
- Medial Forebrain Bundle
- fiber system that runs longitudinally through the lateral hypothalamus, connecting it with the midbrain tegmentum and components of the limbic system
- What is the function of the medial forebrain bundle?
- it carries fibers from noradrengergic and serotoninergic cell groups in the brainstem to the hypothalamus and cortex; it also carries dopaminergic fibers from the substantia nigra to the caudate nucleus and putamen
- Median
- the middle score in series of scores - separates the distribution into two equal groups; preferred measure of central tendency in skewed distributions
- Medulla
- a portion of the brainstem that is located between the spinal cord and pons
- Megalocephaly
- abnormally large head, face, and neck (can also refer to progressive enlargement of the bones in these regions)
- Megaloencephaly
- abnormally large brain (distinct from skull)
- Melodic Intonation Therapy (MIT)
- therapeutic technique often used in speech therapy that pairs verbal uttterances with rhythm and singing; often used with aphasic patients to capitalize on musical capabilities of the nondominant hemisphere
- Melokinetic Apraxia
- hand clumbsiness greater than any weakness or tone impairment that is present(aka innervation apraxia or limb-kinetic apraxia)
- Memory - Anterograde Memory
- ability to learn and recall new information
- Memory - Autobiographical Memory
- Memory or recollection for personal events (one aspect of episodic or declarative memory)
- Memory - Declarative (Explicit Memory)
- Facts, events, or experiences that are consciously recalled (may be episodic or semantic)
- Memory - Echoic Memory
- sensory memory for auditory material (limited duration - 2-3 secs, but large capacity)
- Memory - Episodic Memory
- context specific memory that is often autobiographical; typically preserves temporal and spatial features of the event
- Memory - Explicit Memory (Declarative Memory)
- Facts, events, or experiences that are consciously recalled (may be episodic or semantic)
- Memory - Iconic Memory
- sensory memory for visual information (limited duration - 250-300 msecs, but large capacity); aka echoic storage
- Memory - Immediate Memory
- capacity to maintain information in conscious awareness
- Memory - Implicit Memory (Nondeclarative Memory)
- performance is altered without conscious recollection (e.g., procedural memory, priming, classical conditioning)
- Memory - Long Term Memory
- information retention over long intervals of time
- Memory - Nondeclarative Memory (Implicit Memory)
- performance is altered without conscious recollection (e.g., procedural memory, priming, classical conditioning)
- Memory - Primary Memory
- content of immediate consciousness
- Memory - Procedural Memory
- memory for skills that are not verbalized or consciously performed (e.g., motor learning) - this is a type of nondeclarative memory
- Memory - Prospective Memory
- memory for plans and events anticipated in the future (e.g., appointments)
- Memory - Recent Memory
- ability to form new memories -begins where immediate memory ends
- Memory - Remot Memory
- recollection of information from events of the distant past (e.g., childhood)
- Memory - Retrograde Memory
- ability to recall information that has previously been learned
- Memory - Secondary Memory
- recall of information that is no longer in consciousness
- Memory - Semantic Memory
- context-free memory - reflects general knowledge of symbols, concepts, and rules for manipulating them; rarely concerned with situation in which information was learned
- Memory - Sensory Memory
- first stage of memory processing - storage of a perceptual record
- What are the two types of sensory memory?
- echoic memory and iconic memory
- Memory - Short-Term Memory
- brief retention of information (second to minutes to hours)
- Memory - Source Memory
- memory for the circumstances in which an episodic memory was formed
- Memory - Topographical Memory
- memory for the spatial layot of things
- Memory - Working Memory
- memory system that provides temporary storage so information can be manipulated (limited capacity)
- According to Baddeley, what are the two components of working memory?
- the phonological loop stores acousic and speech-based information whereas the visuo-spatial sketchpad stores visual-spatial information; these are slave systems to the central executive
- Memory Assessment Scales
- 12-subtest battery of attention and memory tests
- Memory Decay
- loss of information recently learned as a function of time
- Memory Quotient
- summary score designed to reflect overall memory ability as assessed by the original WMS
- Memory Span
- amount of information that can be held and repeated back immediately (e.g. digit span)
- Meninges
- the membranes that enclose the brain and spinal cord and line the skull and vertebral canal
- Name the three meninges.
- dura, arachnoid, pia
- Meningioma
- benign tumor that arises from the arachnoid; benign and slow-growing; often successfully surgically resected
- Where are meningiomas typically found within the brain?
- superior sagittal sinus, sphenoid ridge, and close to optic chiasm
- Meningismus
- results from inflammation of the meninges causing regidity in the back and neck; aka nuchal rigidity
- What are the most common causes of meningismus?
- meningitis and subarachnoid hemorrhage
- Meningitis
- inflammation of brain and spinal cord meninges
- Meningitis - Aspetic Meningitis
- nonbacterial meningitis; can be inflammatory, idiopathic, or a viral infection
- Meningits - Bacterial Meningitis
- meningitis caused by bacteria; often accompanied by stiffness of the neck; diagnosis based on examination of CSF; often accompanied by somnolence and mild confusion
- Meningitis - Cryptococcal Meningitis
- meningitis caused by cryptococcus (yeast) infection; often result of opportunistic infection; often presents with headache, cranial nerve involvement, and CSF obstruction
- Meningitis - Mollaret Meningitis
- recurrent aseptic memingitis of unclear origin
- Meningitis - Viral Meningitis
- meningitis caused by a virus; often self-limited; not usually associated with mental status changes
- Meningocele
- a congenital defect in which the meninges protrude through a spinal column causing a bulge under the skin
- Meningocephalitis
- inflammation of meninges and brain - often viral
- Meningomyelocele
- congental defect in which the spinal membranes and spinal cord protrude through a defect in the vertebral column; results in external sac of CSF, incompletely formed meninges, and malformed spinal cord
- Mental Agraphia
- refers to the inability to translate thoughts into written phrases; however, there is no real impairment in linguistic ability
- Mental Retardation
- Intellectual functioning is 2 or more standard deviations below the mean (IQ < 70) and adaptive functioning is impaired
- Mental Status Examination
- Structured interview that typically examines multiple domains (e.g., orientation, attention, memory, language, visuospatial skills, neglect, insight abstraction, etc.) Also often include psychiatric interview.
- Mental Tracking
- Holding information in memory (working memory) while simultaneously manipulating the information (e.g., spell WORLD backwards, letter number sequencing)
- Mesencephalon
- aka midbrain (containes inferior and superior colliculi)
- Meta Analysis
- information from several independent studies is analyzed statistically. Enables one to integrate results from multiple studies to examine trends and calculate an effect size
- Metachromatic Leukodystrophy
- This is a type of metabolic disorder (autosomal recessive)that is accomapnied by loss of myelin and accumulation of metachromatic lipids in the white matter of the brain. Often presents with general cognitive impairments and psychotic features
- Metamemory
- A person's knowledge about his or her own memory system
- Metamorphopsia
- A disorder of the visual system in which shapes and sizes of objects are disorted (may also involve distortion of movement and color)
- Where would you expect the lesion to be in a person with metamorphopsia?
- occiptial or parietal-occipital lobes (usually in the right hemisphere)
- Metencephalon
- the anterior portion of the hindbrain that includes the pons and cerebellum
- Method of Loci
- a type of mneumonic technique in which items one is trying to remember are visualized in space
- Meyer's Loop
- this collection of fibers forms part of the optic radiation; it starts in the lateral geniculate nucleus, crosses over the temporal horn of the lateral ventrical and into the temporal lobe
- What symptoms often result from a lesion in Meyer's loop?
- superior homonymous quadrantanopsia (visual loss of upper quadrant contralateral to lesion location)
- Microcephaly
- "small head"; often associated with mental retardation
- MicroCog
- computerized cognitive screening instrument
- Micrographia
- very small hndwriting (often illegible); a form of hypometria
- What area of the brain is usually associated with micrographia?
- basal ganglia impairment (e.g., Parkinson's disease)
- Micropsia
- visual illusion in which objects appear to be moving away or getting smaller; sometimes a symptom of partial seizures
- Middle Fossa
- one of the three large depressions on the floor of the cranial cavity (aka middle, posterior and anterior fossi); the middle fossa lodges the temporal lobes laterally and the hypothalamus medially
- Mill Hill Vocabulary Scale
- a vocabulary test used to assess verbal intelligence
- Millon Clinical Multiaxial Inventory (MCMI)
- a personality instrument; scales correspond to DSM-IV diagnoses
- Mindblindness
- aka agnosia
- Minimal Brain Dysfunction
- this term is sometimes used to describe a learning disability when there is no clear evidence of a neurologic disorder
- Minnesota Multiphasic Personality Inventory
- a personality measure consisting of 10 empirically derived clinical scales; intended to detect psychopathology
- Mirror Reading
- task in which subject must read reflected images of words; implicit memory task
- Mirror Tracing / Mirror Drawing
- task in which subject must trace or copy a shape while viewing shape and hand in a mirror; implicit memory task
- Mnemonics
- methods or techniques for improving memory
- Mnestic
- relating to memory
- Mode
- score that occurs most frequently in a distribution (one type of measure of central tendency)
- Moderator Variables
- moderator variables systematically vary with a variable of interest and affect the accuracy of prediction
- Monoamine Oxidase (MAO)
- an enzyme that is distributed widely throughout the body; involved in oxidative breakdown of several neurotransmitters, including dopamine, serotonin, and norepinephrine
- Monoamine Oxidase Inhibitor (MAOI)
- a type of antidepressant medication that inhibits the action of MAO
- Mood
- a subjective emotional state (e.g., anger, depression) that is usually sustained
- Mood Disorders
- DSM-IV classified disorders in which mood disturbance is the primary feature
- Morbidity
- "any deviation from psychological or physiological well-being" (per Loring, 1999)
- Morpheme
- smallest unit of language that still has meaning
- Mortality
- death; fatal outcome
- Motor Impersistence
- patient can form a posture, but cannot maintain it; often considered a type of apraxia; many times accompanied by general cognitive impairment
- How does one test motor impersistence?
- ask patient to keep eyes closed, tongue protruded, or mouth open
- Motor Neglect
- patient is aware of a stimulus and the appropriate response to the stimulus, but is unable to respond
- Motor-Free Visual Perception Test (MVPT)
- a type of visuoperception test that does not require motor movement
- Movement Disorders
- disorders caused by damage to the extrapyramidal motor system; result in involuntary movements
- What are some common movement disorders?
- tremor, dystonia, dyskinesia, chorea, ballismus, motor tics
- MRTP
- a type of neurotoxin that mimics parkinsonism (often used in animals as a model of Parkinson's disease)
- MTD
- abbreviation standing for "maximum tolerated dosage"
- Multidimensional Scaling
- a multivariate method in which subjects are asked to identify similarities and differences among stimulus items in order to assess scaling of a stimulus
- Multilingual Aphasia Examination (MAE)
- a language battery often used to assess aphasic patients; assesses expressive, receptive, and repetition skills
- Multiple Correlation
- a correlation coefficient that reflects the relationships between criterion and predictor scores (denoted by a capital R)
- Multiple Sclerosis (MS)
- a type of autoimmune diesease in which demyelination occurs; many focal inflammatory lesions occur in the white matter (more common in females)
- Multiple Subpial Transection (MST)
- a surgical technique often used to treat epilepsy in which shallow cuts are made into the gray matter in an attempt to disconnect the horizontal white matter fibers; most often performed in eloquent brain regions
- Muti-system Atrophy (MSA)
- an atypical parkinsonian disorder in which thre is autonomic insufficiency with degeneration of multiple regions, including basal ganglia, cerebellum, spinal cord, and peripheral sympathetic ganglia (considered a "Parkinson's Plus" syndrome)
- Multivariate Analysis of Variance (MANOVA)
- an extension of ANOVA in which there are two or more dependent variables
- Munchausen's Syndrome
- a type of disorder in which patients continuously present to hospitals or doctors offices for treatment of acute illnesses that do not actual exist; incentive appears to be playing the "sick role."; this is a type of factitious disorder
- Munchausen's Syndrome by Proxy
- same as Munchausen's syndrome, only individual's symptoms are reported by his or her caregiver to receive attention
- Mutism
- inability to produce speech
- What types of lesions and/or medical conditions might result in mutism?
- lesions to Broca's area in dominant hemisphere; lesions in insula; conversion disorder; depression or other psychiatric disorder
- Myalgia
- pain of the muscles
- Myasthenia Gravis
- neuromuscular disorder characterized by impaired transmission of nerve impulses following an autoimmune attack on acetylcholine receptors; often involves drooping of eyelids, double vision, impairment of speech and swallowing; also progressive fatigue and generalized weakness of the skeletal muscles, especially those of the face, neck, arms, and legs
- Myelencephalon
- aka medulla
- Myelin
- white fatty material, composed chiefly of lipids and lipoproteins, that encloses certain axons and nerve fibers; acts as electrical insulator that speeds neural transmission
- Where is myelin produced?
- by oligodendroglia in the CNS and Schwann cells in the PNS
- Myelitis
- spinal cord inflammation
- Myoclonus
- involuntary muscle jerks that occur suddenly; associated with some nervous system disease
- Myopathy
- muscle disorder/disease
- Myotonia
- Tonic muscle spasm or temporary rigidity of one or more muscles
- Myotonic Dystrophy
- progressive autosomal dominant disease marked by atrophy and general weakness of muscle; also involves decreased vision, ptosis, and slurred speech
- N.A.
- Patient N.A. was injuried by a fencing foil that penetrated the dorsomedial thalamus; Clinically, he showed significant anterograde memory deficits
- Nanocephaly
- an abnormally small head or skull
- Narcolepsy
- disorder in which patient suffers from excessive sleepiness and has sudden and uncontrollable sleep attacks during wakeful hours; often accompanied by paralysis (i.e., cataplexy)
- What is the best way to test for narcolepsy?
- This disorder is often diagnosed using a multiple sleep latency test. Finding show that little or no-REM preceeds the sleep attacks
- Nasolabial Fold
- the crease that runs from the sides of nose to the corner of the mouth of the same side
- If a nasolabial fold is flattened in appearance, what does this indicate?
- facial weakness
- National Adult Reading Test (NART)
- this is a test of reading that consists of irregularly spelled words (versions include Noarth American Adult Reading Test and the American National Adult Reading Test)
- What is the NART typically used for?
- to exstimate premorbid cognitive functioning
- Neglect
- lack of attention or response to environmental stimuli (e.g., visual, auditory, tactile) contralateral to a lesion in the absence of senosry or motor deficits
- Name six possible compenents of a neglect syndrome.
-
1) hemi-inattention;
2) extinction to double simultaneous stimulation;
3) allesthesia & allokinesia;
4) hemi-akinesia;
5) asomatognosia
6) anosognosia or anosodiaphoria - What are some common tasks used to assess neglect?
- line bisection, clock drawing, simple line drawings (e.g., flower)
- Neologism
- a made up or "new" word that is nonsensical or unrecognizable; neologisms are often observed as a symptom of certain psychotic disorders, like schizophrenia
- NEPSY
- a neuropsycholog9ical battery of tests designed for children ages 3-12; measures all primary cognitive domains
- Neural Tube
- a dorsal tubular structure in the vertebrate embryo that eventually becomes the brain and spinal cord
- At what point in embryonic development is the neural tube formed?
- Week 3
- Neuralgia
- sharp, severe pain that travels along the course of one or more nerves
- Neuritic Plaques
- brain material that consists of amyloid and degenerated dendrites; this pathology is commonly found in the brains of AD patients (aka senile plaques)
- Neuritis
- inflammation of a nerve or nerves that is often characterized by pain, loss of reflexes, and muscle atrophy. May also see anesthesia, paresthesia, or paralysis
- Neurobehavioral Rating Scale
- brief behavioral description scale that makes use of interview and mental status information; this scale was modified from the Brief Psychiatric Rating Scale
- Neuroblastoma
- a type of malignant tumor that consists mainly of neuroblasts; most commonly seen in children 10 years and younger
- Where do neuroblastomas most commonly originate?
- in the autonomic nervous system or adrenal medulla
- Neurofibrillary Tangles
- a pathological accumulation of twisted neural elements composed of abnormally formed tau protein that is found chiefly in the cytoplasm of nerve cells of the brain, especially the cerebral cortex and hippocampus; this pathology is commonly found in the brains of patients with AD
- Neurofibromatosis
- autosomal dominant genetic disorder that is accompanied by developmental changes in the nervous system, muscles, bones, and skin; often with spots of increased skin pigmentation, peripheral nerve tumors, and other dysplastic abnormalities of the skin, nervous system, bones, endocrine organs and blood vessels (aka von Recklinghausen's disease
- Neuroglia
- supportive cells in the nervous system (aka glia)
- Neuroleptic Drugs
- Medications commonly used to treat psychotic symptoms (aka major tranquilizers or antipsychotics)
- Neuroleptic Malignant Syndrome
- sometimes occurs as a reaction to drugs (e.g., neuroleptics, tricyclics, lithium, cocaine, or amphetamines); symptoms include hyperthermia, muscle rigidity, and encephalopahty; mortality rate with this syndrome is high
- Neuroma
- a tumor composed mostly of nerve cells and fibers or growing from a nerve
- Neuromuscular Junction
- end of a motor neuron where skeletal muscle fibers are innervated
- Neuropahty
- general term used to refer to nonspecific lesions in the peripheral nervous system resulting in functional or pathological changes
- Neuropharmacology
- the study of medications (foreign and endogenous) that affect the nervous system
- Neuropsychiatric Inventory
- this care-giver report measure examines 10 behavioral domains often affected in neuropsychiatric disorders (e.g., hallucinations, delusions, anxiety, disinhibition, etc.); employs a screening strategy to save time
- Neuropsychological Deficit Score
- from the Halstead-Reitan Neuropsychological Battery; refers to the summary score obtained from the battery of 42 measures
- Neurosensory Center Comprehensive Examination for Aphasia
- this battery contains 20 language subtests (e.g., naming, sentence repetition, digit span, fluency, etc.)
- Neurosyphilis
- syphilis of the central nervous system; often marked by frontal lobe dysfunction beginning with apathy and changes in personality. Other symptoms include impaired judgment, mood swings, impariements in memory and attnetion; poor hygiene, and wandering
- Neurotoxin
- any substance that destroys or damages nerve tissue
- Neurotransmitter
- nervous system chemical that travels through nerve cells and alters postsynaptic cells; can be excitatory or inhibitory
- Neurotrophic Factors
- neuropeptides (naturally occuring) that regulate and enhance neuronal growth and function in peripheral and central nervous systems (e.g. nerve growth factor)
- Niacin Deficiency
- vitamin deficiency that results in confusion, memory difficuties, irritability, and apathy (may be seen in patients with history of alcoholism)
- Nidus
- a central point (e.g. point of abnormal development in AVM or focus of an infection)
- Nigrostriatal
- pathway that joins the corpus striatum and the substantia nigra
- What is the function of the nigrostriatal pathway?
- this pathway plays a large role in transmission of dopamine; if dopamine becomes reduced in this area, rigidity, akinesia, and tremor often result
- NMDA
- a receptor for glutamate - opens neuron channels to allow influx of calcium
- What are some of the known functions of NMDA?
-
involved in:
1) memory
2) migration of embryonic neurons
3) excitotoxic neuron death - Nocicepton
- perception of painful sensations
- Nociferous Cortex
- term introduced by Penfield to refer to brain regions that "actively doing bad things"; often used to refer to cortex assocaited with brain lesion in epilspy that impairs functioning regions distant from the epileptogenic focus due to propagation of abnormal discharges
- Node of Ranvier
- constriction in the myelin sheath of a nerve fiber; occurs at varying intervals along the nerve cell
- Non Compos Mentis
- "not of sound mind"; usually means individual cannot be held legall responsible, because they are mentally incompetent; could also mean that one is unable to manage their own affairs
- Nonepileptic Seizures (NES)
- events that appear similar to epileptic seizures, but are not accompanied by abnormal electrographic discharges on EEG
- Nonsense Syllable
- a nonsense word that usually consists of a consonant-vowel-consonant combination; the resulting word is not part of the normal language (e.g., gaf, nid)
- Nonverbal Learning Disabilities (NVLD)
- this disorders consist of deficitis in motor and senory integration, visuospatial-organizational abilities, or difficulty with novel and complex situations; these disorders also are often accmpanied by poor social skills
- Normal Distribution
- distribution of scores that is symmetric around the mean (i.e., bell shaped curve)
- What are the characteristics of a normal distribution?
- 68% of scores fall between -1 and +1 sds; 95% fall between -2 and +2 sds, and 97.7 fall between -3 and +3 sds
- Nuclear Magnetic Resonance
- the absorption or emission of electromagnetic radiation of a specific frequency by an atomic nucleus that is placed in a strong magnetic field
- Nucleus
- group of nerve cell bodies in the nervous system
- Nucleus Basalis of Meynert
- one of a number of nuclei in the basal forebrain that extends from the STN to the bottom of the third ventricle
- Null Hypothesis
- hypothesis that there will be no difference between experimental conditions
- Nystagmus
- rapid movements of the eyes that are involuntary (may be horizonal vertical, rotary, or mixed)
- What type of lesions cause nystagmus?
- cerebellar, vestibular, or brainstem