Neuropsychology Exam: Assessing Human Brain Structure and Function ( UPDATED DETAILED SOLUTIONS)

Neuropsychology Exam 2 Review Assessing Human Brain Structure and Function Neuropsychological Research Methods - Main categories of research methods: o Examine the effects of brain damage o Correlate brain anatomy with behavior o Record brain activity during behavior o Examine the effects of stimulating particular parts of the brain Brain Pathology and Injury - Six main types o Tumors o Cerebrovascular accidents/ disorders o Infections o Neurotoxins o Closed-head injuries o Genetic factors Brain Tumors - Tumor (“Neoplasm” [i.e. New Tissue]) o Morbid enlargement or new growth of tissue o Cell division and proliferation is uncontrolled  Malignant: Progressive (i.e. keeps growing)  Benign: cell growth arrested • Still capable of producing neurobiological problems - Brain tumors o Local o Metastasized (i.e. infiltrating) Characteristics of Brain Tumors - Local tumors arise from any local cells residing in affected orgam o Blood vessels o Meninges o Glial cells (Glioma)  e.g., astrocytes  Ependymal cells lining ventricles  Acoustic neuroma (mylenating cells surrounding auditory nerve)  Note: Cancerous neurons are rare. Infiltrating Tumors - Metastasis o Circulation and spreading of cancer cells to locations distal to organ/tissue of origin - Metastasis tumors in secondary sites of not the same type as the infiltrating organ/tissue - Growth in secondary sites upsets metabolic needs and functions of the resident cells o i.e., Primary tumor found in chest – Secondary (metastastic) tumor found in brain Cerebral Blood Supply - The internal carotid artery and vertebral artery provide the major arterial blood supply to the Brain. - Circle of Willis: o A critical arterial circle at the base of the brain. o The circle of Willis receives all the blood that is pumped up the two internal carotid arteries that come up the front of the neck. o All the principal arteries that supply the two halves of the brain (hemispheres) branch off from the circle of Willis. Cerebrovascular Accidents - Cerebral Accident o Sudden damage due to disruption of cerebrovascular system - Stroke o A CVA that results in sudden reduction or loss of:  Consciousness  Sensation  Voluntary movement o Causes of Stroke  Blockade of brain artery (or arteries) • Clot (i.e., thrombus – clump of coagulated blood) • Embolus (e.g., air bubble or some other particle) • NOTE: embolus typically a substance that travels in blood until it creates a blockage  Rupture of blood vessel(s)  Hemorrhage Infections - Inflammation o Invasive event precipitates physiological events that result in:  Pain  Vasodilation (redness)  Tissue Swelling • Fluid build-up (edema) • Cell infiltration o Cells of the immune system o Immune cells produce chemical messengers that:  Recruit more cells  Change local conditions (e.g., further vasodilation) - Invasion of the CNS by microbial agents o Viruses (encapsulated nucleic acid – e.g., DNA or RNA) o Bacteria o Fungus - Inflammation results from presence of microbial agents - Meningitis o Inflammation of meninges o Fungal is most serious - Herpes Virus o Genital, oral (cold sores) blistering o Infection can occur outside CNS o Once in nervous system:  Remains dormant  Upon activation, leaves cells and induces immune response  This can have serious consequences o Encephalitis: Affects medial temporal lobe (and limbic system in general)  Seizures (Epileptic)  Hallucinations  Muscle Stiffness  Personality changes • Impaired judgment • Dementia - Indirect: o Cytokines and antibodies produced by immune system o Infiltrating cells (of immune system) - Produce pathology and behavioral changes o Demylinating diseases  Multiple Sclerosis o Neurodegenerative diseases  Infections not necessarily causative (i.e., may contribute to neurological and physiological changes o General, temporary alterations in behavior - Myasthenia Gravis o Marked by muscular fatigue after activity  Ptosis (drooping eyelids)  Diplopia (double vision)  Weak voice  Difficulty chewing and swallowing  In some people, ONLY the limbs are affected o Females Males o Typical age onset: 30s o Treatment  Acetylcholine therapy for symptom removal  Thymectomy and immunosuppressive therapy - Multiple Sclerosis o Formation of sclerotic (“hard”) plaques o Plaques contain demylinated axons o When axon demylinates, cell dies o Accumulation of infiltrating immune cells around areas of plaque formation is thought to be a causative agent o Therefore, MS is a suspected autoimmune disease (i.e., when the immune system attacks self tissue)