Some Common Nutritional Deficiencies Korsakoff’s Disease – related to thiamine deficiency Folic acid/folate deficiency – implicated in a progressive condition of mental deterioration with concomitant cerebral atrophy. It is also implicated in spina bifida/neural tube defects. Vitamin deficiencies – affect anorexic young women (who show subtle neuropsychological deficits), and in the elderly (whose intake of … Read more
Definitions Visual-perceptual Form or pattern discrimination; color, shape, features of object regardless of location Visual-spatial Processing of visual orientation or location in space; depth, motion “Types” of visual-spatial processes Object localization- ability of any sensory system to locate object in space Line orientation- human cortex has detectors of line orientation; damage to right posterior disrupts … Read more
Dopamine Synthesis and Metabolism Phenylalanine —> Tyrosine —> DOPA —> Dopamine (DA) Anatomy Synthesized mainly in neurons located in the ventral midbrain (substantia nigra pars compacta & ventral tegmental area) Three projection systems: Nigrostriatal Pathway: Substantia nigra to caudate and putamen (implicated in Parkinson’s) Mesolimbic Pathway: Midbrain to limbic structures (implicated in positive symptoms of … Read more
Mental Status Level of Alertness, Attention, and Cooperation: Can use test of working memory and attention (e.g., digit span; w-o-r-l-d/d-l-r-o-w) What is being tested? Altered consciousness can stem from: Damage to brainstem reticular formation Bilateral lesions of the thalami or cerebral hemispheres Can be mildly impaired in unilateral cortical or thalamic lesions Toxic or metabolic … Read more
Schizophrenia Brief History Kraeplin (1919) came up with first definition (called it dementia praecox) Blueler (1950) introduced the term “schizophrenia” (Bleuler’s 4 A’s: Association, Affect, Ambivalence, and Autism) Schneider (1959) came up with 11 pathognomonic symptoms (Schneiderian First Rank Symptoms) Crow (1980) proposed that schizophrenia be divided into 2 major syndromes (Type I and Type … Read more
History CTs developed in the 1970’s — MRIs developed in the 1980’s Plain Film Analysis Used to evaluate structures of skull, facial bones, and sinus Usefulness declined with advent of CT and MRI Still used in detection of fractures, abnormal calcifications, developmental abnormalities, osteolytic or osteoblastic disorders. For example Identification of neoplasms Premature closing (craniosynostosis … Read more
Basic Macroscopic Organization of the Nervous System The CNS arises from a sheet of ectodermal cells that folds over during embryological development to form the neural tube CNS = Brain and spinal cord PNS = Cranial nerves and ganglia Spinal nerves and dorsal root ganglia Sympathetic and parasympathetic nerves and ganglia Enteric nervous system Main … Read more
DEFINITION Neglect: a failure to respond to, report, or orient to novel or meaningful stimuli presented to the side opposite the lesion NOT attributable to sensory, motor, or memory deficits deficit of looking, detecting, listening, and exploring NOT seeing, hearing, or moving Like aphasia or amnesia, neglect is a “network syndrome” and represents damage to … Read more
General Characteristics Multiple sclerosis is a multifocal demyelinating disease – the disease causes the destruction of the myelin sheath of nerve fibers – scar-like lesions called sclerotic plaques form in the areas where the demyelination has occurred and block or distort the normal transmission of nerve impulses. Incidence and prevalence vary geographically fewer cases near … Read more
Spinal Cord: Central gray matter – neuronal cell bodies and synapses Peripheral white matter – ascending/descending fiber pathways (motor and sensory) Muscle Unit: A single motorneuron and all of its muscle fibers Alpha motorneuron – largest cells of spinal cord and “final common pathway” from CNS to periphery. Each one usually innervates many muscle fibers … Read more