CASE 1 : 71 YR OLD STROKE VICTIM From the CAT scan we have 3 lesion sites involved : 1. A large right occipital-temporal lesion 2. A sub-cortical lesion of the left occipital lobe 3. Mild global atrophy Considering the age and health of the patient the mild global atrophy is of little consequence in the absence of dementia. The Prosopagnosia, is consistent with an area 20/21 right side lesion. The topographic memory deficit is probably a result of damage to areas 18/19 on the right.The naming misidentification problem is usually characteristic of lesions in area 18-21 on the left as well as damage to the corpus collusum. The damage to the left visual field is a bit unexplained though. The type of deficit described (hemanopsia w/o macular sparing) would indicate a right optic tract lesion while no such lesion was mentioned in the neurological analysis. Question 1: If there is no damage to the optic tract is this patient "really blind" in the left visual field or is this a case of "cortical blindness". A standard test would be as follows: Tachistoscopic presentation of various test data into each visual field. test data consists of letters, words and geometric figures. Immediately after presentation the subject is asked to make a forced choice of the form "which of these stimuli did you just see." Given that the subject responds at approximately chance then she is truly "blind" in that filed and the lesion is most likely in the optic tract. Given that left visual field responses are above chance in ANY of the above stimulus sets then what we have is a case of corical blindness with a probable disconnection syndrome. Question 2: The patients emotional changes especially her disconecction of esthetics and vision suggest a disconection syndrome between the left hemisphere visual area and some "right hemisphere esthetic association cortex". Her ability to verbalize esthetics and consequently "appreciate" tehm indicates a sparing of auditory-association cortex pathways. This disconnection does make some sense in light of the damage to the collosal area revelaed by the CAT scan. It may be at least partially related to the subcortical left hemisphere damage seen by the CT scan. A method of testing for the existance of this disconnection syndrome can be as follows. Present to the subject conflicting emotionally laden stimuli in two different modalities. Namely a happy picture and a sad series of sounds. In the first instance have the subject rate whether she is feeling happy or sad on a 1-7 scale . Then allow her to verbalize the visual scene. The ratings should be skewed in the first case toward the auditory stimulus and in the second scene toward the verbalized visual stimulus. CASE 2: DEMENTED WF The only "sure way" to diagnose types of presenile dementia is through histological data at autopsy (presence of neurofibril plaques and tangles.) Barring that it is difficult in many cases to accurately diagnose the problem. W.L.P's history and age would probaly lead us to believ that she had come down with a case of early Alzheimer's disese. The question to be asked here I think is as follows: "Does W.L.P. have AD and what is the true progression of her condition?" 1. Chemically AD is characterized by a decrease in cerebral metabolic rate and abnormalities in central neurotransmitter production of the cholinergic system. (esp. ACh-ase AChE-ase and CAT-ase. Investigations from this viewpoint would led one to PET scans and transmitter assays of the patient versus non-demented age matched controls and younger control subjects. 2. The question now is there a way to diffrentiate dementias neuropsychologically so that a treatment can be begun? Some work at the Clinic for Nervous and Mental Disese at catholic University in Rome has suggested the se of a "Mental deterioration Battery" which consist of 3 verbal and 3 visuopatial tasks that seem to more clearly define various dementias. 1. WF - Word Fluency- as many words beginning with a specific letter as you can name in 1 min 2. PC -Phrase construction - Given 2 or 3 words construct a phrase. 3. Rey's 15 words 15 words are read allowed and the subject is asked to recall as many as possible (list repeted 5 X) 15W-ST Immediate recall of as many words as possible 15W-LT 15 min delayed recall with interdispersed visuospatial task. 4. CPM- raven's colored progressive matrices 5. IVM- immediate visual memory- using CPM 6. 2. PC -Phrase construction - Given 2 or 3 words construct a phrase. 3. Rey's 15 words 15 words are read allowed and the subject is asked to recall as many as possible (list repeted 5 X) 15W-ST Immediate recall of as many words as possible 15W-LT 15 min delayed recall with interdispersed visuospatial task. 4. CPM- raven's colored progressive matrices 2. PC -Phrase construction - Given 2 or 3 words construct a phrase. 3. Rey's 15 words 15 words are read allowed and the subject is asked to recall as many as possible (list repeted 5 X) 15W-ST Immediate recall of as many words as possible 15W-LT 15 min delayed recall with interdispersed visuospatial task. 4. CPM- raven's colored progressive matrices 5. IVM- immediate visual memory- using CPM 6. Copy Design CD- Copy a figure (star, horse, cube) CDL-Draw same object from memory with the help of landmarks Fig 1 Reports the pattern of results for the tests obtained by the Rome group. This data when compared to the results of similar test on W.L.P. would aid in diffrentiation. The heavy production aphasia is could be a result of excess deterioration of the verbal memory system. CASE 3. SOMATOSENSORY 21 yr old Jacksonian seizures M.G. underwent a right osteoplastic craniotomy to relieve Jacksonian seizures with removal of an abnormal area of brain almost entirely in POST- CENTRAL gyrus. After the excision though M.G. could not squeeze the dynamometre at all. She seem sto have lost all position sense as well as senses of touch and pressure. Her deficit appears to not be motor but somatosensory. She seems to have lost the position and pressure feedback mechanisms in her left arm. The question most obvious here is what is the extent of her deficit ie what was the result of removing this area of somatosensory cortex. The types of tests will come in 6 areas. DETECTION 1. 2 point localization 2. Posiion sense (hold middle phalanx of each finger and move distal phalanx). 3. Vibrattory sense 4. Light touch/pressure sensitivity 5. Roughness. DISCRIMINATION 1. Weight 2. Shape and form 3. Roughness STEREOGNOSIS 1. Object Identification 2. Shape perception 3. Perception of 3-D objects DIRECTION PERCEPTION Series of angled lines (tactual) are set up and subject is asked to detremine the angle at which they are pointing MEMORY &LEARNING A series of tactual mazes are presented to the subject. Can they be learned?? NEGLECT Does the subject neglect one side or body part. If the original "Position sense loss" thesis is correct the subject should be markedly impaired in the the memory &learning, stereognosis and direction perception tasks while being largely intact for the rest. Controls: For patient 1. a. Normal age matched b. (ideal) right occipital temporal only c. (ideal) left subcortical b&c will tell us if the left subortical lesion is responsible for the hypothesized disconnection syndrome. Patient 2. Messy... a. Age matched controls b. Younger/adult controls for the compariosn study Patient 3. a. Normal age matched controls with dural invasion if possible. b. Epileptic seizure controls.