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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

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