Sunday, November 29, 2009

WHIMS MRI study brain atrophy and estrogen

NEUROLOGY 2009;72:135-142
 
1403 women aged 71-89, a subset of WHI trial, were scanned on average four years apart.  Frontal lobe volume was less at followup in women in estrogen or estrogen plus progesterone arms.  Temporal lobe and total brain volume were not affected as markedly. The adverse effects are most evident in women experiencing cognitive deficits before initiating hormone therapy.

The cognitive measure used was the modified MMSE 3M

  1. Teng EL, Chui H. The Modified Mini-Mental State (3MS) Exam. J Clin Psychiatry 1987;48:314–318.

Confabulation and other delusional syndromes

Confabulation is usually associated with memory (medial temporal or diencephalic) and executive (bifrontal) dysfunction.7-9
 
  1. Benson DF, Djenderedjian A, Miller BL, et al. Neural basis of confabulation. Neurology 1996;46:1239–1243.[Abstract/Free Full Text]
  2. Moscovitch M, Melo B. Strategic recall and the frontal lobes: evidence from confabulation and amnesia. Neuropsychologia 1997;35:1017–1034.[Medline]
  3. Johnson MK, Hayes SM, D'Esposito M, Raye CL. Confabulation. In: Grafman J, Boller F. Handbook of Neuropsychology,

The anterior parahippocampal cortex (perirhinal cortex, Brodmann areas 35 and 36) is activated by familiarity, while the hippocampus and posterior parahippocampal cortex mediate recollection.49 Perirhinal cortex stimulation evokes déjà vu and déjà vécu (already experienced).50 Further, the right hemisphere dominates in familiarity decisions14,48; déjà vu is more common with right than left temporal lobe seizures or stimulation.48,51 Lesions that destroy or isolate stimuli from right perirhinal cortex may lead to loss of familiarity (e.g., Capgras syndrome) while hyperfamiliarity (i.e., misidentifying strange people as familiar [Fregoli syndrome]) may result from overactivity in right perirhinal cortex from stimulation or disinhibition. Two cases of nondelusional hyperfamiliarity for faces resulted from left-sided lesions (lateral temporal-occipital and anterior cingulate),52,53 possibly disinhibiting right hemisphere areas that imbue faces or places with familiarity.

  1. Gainotti G. Face familiarity feelings, the right temporal lobe and the possible underlying neural mechanisms. Brain Res Rev 2007;56:214–235.[Medline]
  2. Bowles B, Crupi C, Mirsattari SM, et al. Impaired familiarity with preserved recollection after anterior temporal-lobe resection that spares the hippocampus. Proc Natl Acad Sci 2007;104:16382–16387.[Abstract/Free Full Text]
  3. Vignal J-P, Maillard L, McGonigal A, Chauvel P. The dreamy state: hallucinations of autobiographic memory evoked by temporal lobe stimulations and seizures. Brain 2007;130:88–89.[Abstract/Free Full Text]
  4. Mullan S, Penfield W. Illusions of comparative interpretation and emotion. Arch Neurol Psychiatry 1959;81:269–284.[Abstract/Free Full Text]
  5. Vuilleumier P, Mohr C, Valenza N, Wetzel C, Landis T. Hyperfamiliarity for unknown faces after left lateral temporo-occipital venous infarction: a double dissociation with prosopagnosia. Brain 2003;126:889–907.[Abstract/Free Full Text]
  6. Nente F, Carrillo-Mezo R, Mendez MF, Ramirez-Bermudez J. Pathological hyperfamiliarity for others from a left anterior cingulate lesion. J Neuropsychiatry Clin Neurosci 2007;19:345–346.[Free Full Text]
Hughlings Jackson and right hemisphere expression, and callosal syndromes
  1. Jackson JH. Evolution and dissolution of the nervous system. In: Taylor J, ed. Selected Writings of John Hughlings Jackson, Volume 2. New York: Basic Books; 1884/1958:45–75.
  2. Sperry RW, Zaidel E, Zaidel D. Self recognition and social awareness in the deconnected minor hemisphere. Neuropsychologia 1979;17:153–166.[Medline]
  3. Gazzaniga MS. Cerebral specialization and interhemispheric communication. Brain 2000;123:1296–1326.
  4. Gazzaniga MS. The split brain revisited. Sci Am 1998;279:50–55.[Medline]
ego boundaries response to next patient syndrome
  1. Bogousslavsky J, Regli F. Response-to-next-patient-stimulation: a right hemisphere syndrome. Neurology 1988;38:1225–1227.[Abstract/Free Full Text]

Saturday, November 28, 2009

Neuropsych and carotid stenosis

M. Silvestrini, MD, I. Paolino, MD, F. Vernieri, MD, C. Pedone, MD, R. Baruffaldi, MD, B. Gobbi, MD, C. Cagnetti, MD, L. Provinciali, MD and M. Bartolini, MD . Cerebral hemodynamics and cognitive performance in patients with asymptomatic carotid stenosis. NEUROLOGY 2009;72:1062-1068
Objective: The aim of this study was to investigate whether the presence of severe internal carotid artery stenosis may be associated with different cognitive performance in relation to the side of the stenosis and its hemodynamic consequences.

Methods: Eighty-three patients with asymptomatic severe unilateral internal carotid stenosis were included. A neuropsychological investigation including Verbal Fluency using phonemic and category access, Coloured Progressive Matrices, and Complex Figure Test Copy was performed. Each patient underwent an assessment of cerebrovascular reactivity (CVR) to hypercapnia with transcranial Doppler ultrasonography using the breath-holding index (BHI). Thirty healthy subjects comparable for demographic characteristics and vascular risk profile served as controls. Subjects with carotid stenosis were classified into two groups: preserved CVR (BHI 0.69), 48 patients (25 with left and 23 with right stenosis); and impaired CVR (BHI <0.69), 35 patients (19 with left and 16 with right stenosis).

Results: Subjects with left stenosis and reduced CVR had significantly lower performances at phonemic verbal fluency with respect to controls and the other groups of stenosis. In subjects with right stenosis and reduced CVR, scores obtained in Coloured Progressive Matrices and in Complex Figure Test Copy were significantly lower with respect to the other groups.

Conclusions: These results suggest that an alteration of cerebrovascular reactivity may be responsible for reduction in some cognitive abilities involving the function of the hemisphere ipsilateral to carotid stenosis. Such findings may be of interest for providing a more comprehensive indication to surgical treatment in subgroups of subjects with asymptomatic carotid stenosis.


Friday, November 27, 2009

Devinsky on localization of Capgras, Fregoli,anosognosia and related conditions

Neurology 2009 Views and Reviews
ABSTRACT When the delusional misidentification syndromes reduplicative paramnesia and Capgras syndromes result from neurologic disease, lesions are usually bifrontal and/or right hemispheric. The related disorders of confabulation and anosognosis share overlapping mechanisms and anatomic pathology. A dual mechanism is postulated for the delusional misidentification syndromes: negative effects from right hemisphere and frontal lobe dysfunction as well as positive effects from release (i.e., overactivity) of preserved left hemisphere areas. Negative effects of right hemisphere injury impair self-monitoring, ego boundaries, and attaching emotional valence and familiarity to stimuli. The unchecked left hemisphere unleashes a creative narrator from the monitoring of self, memory, and reality by the frontal and right hemisphere areas, leading to excessive and false explanations. Further, the left hemisphere's cognitive style of categorization, often into dual categories, leads it to invent a duplicate or impostor to resolve conflicting information. Delusions result from right hemisphere lesions. But it is the left hemisphere that is deluded.
(from text of article in Neurology)
Reduplicative paramnesia and Capgras syndrome cases with unilateral brain lesions strongly implicate the right hemisphere, usually frontal with variable temporal or parietal involvement.
Other points of interest

Luria tests from Higher Cortical Functions in Man



Motor:
p.417 and on
1. copy hand postures- suggested to do with little visual input.
2. bimanual task-- closes patient eyes, places one hand in posture and asks patient to place opposite hand in same posture.
3. cites Head's test with mirror image imitation and imitation with same (ie left or right hand). Also, do imitation while touching left eye, right ear etc.
4. cites Ozeretskii (1930)- place one hand in fist, the other outstretched and alternate movement (premotor)reciprocal coordination
5. Place both hands in front, alternately tap twice with right hand, once with the left, with smooth transitions, and then switch the sides. Request the test to be done quickly.
6. Ozeretskii again- if one hand is paretic, do "fist ring" of other hand, thrust hand forward alternately making a fist, and a ring, testing premotor again.
7. Eidinova and Pravdina-Vinarskaya-- (1959)-- Start with a bent elbow, straight fingers, and ask patient to extend elbow, and at same time change hand position to a fist, rapidly. repeating. May eventually change the instruction to the opposite.
8. More difficult-- fist edge palm
9. Piano imitation-- ask patient on table to imitate playing piano with thumnb and first finger of one hand, and fingers 1-5 of other at same time. (and various combinations).
10. Doing above tasks with self spoken cues
11. writing alternating components (Russian equivalent of m and n)
12. Observation of everyday tasks (buttoning, lacing a shoe)
13. States that performance of imaginary acts such as pouring tea are sensitive but not equally susceptible to analytics.

Oral praxis p 425
1. Basic exam-- if patient can bare teeth once, ask him to sustain task for a long time.
2. touch tongue to upper lip, protrude it and keep it out for a while, looking for synkinesis, smoothness of movement
3. Stretch lips, roll up tongue, puff the cheeks and alternate these.
4. "Integrative tests" are chewing, spitting, kissing and whistling
5. Rid mouth of actual edible food which may be impossible even though above are preserved.

Thursday, November 26, 2009

Selnes and Gordon: Quick office neuropsych testing




A few novel suggestions by these two:
Orientation: Add time of day to questions to increase sensitivity
Attention: Use forward-reverse digit span rather than serial sevens
Memory-- NCSE (AnnInt Med) 1987 uses 4 words and a recognition memory function is better than three words recall.
Language-- use brief screening test, progress to more difficult
Visuoconstruction-- draw a clock face or Necker cube is better than copy test of MMSE
Perceptualability-- tell time from clock face
Frontal lobe-- 3 hand test of Luria no suggestions
Psychomotor speed-- write alphabet as quickly as possible. Normal isless than 20 seconds, abnormal ismore than 30 seconds.

Clock Drawing Test notes on

The test incorporates a broad range of cognitive requirements making it an effective screening instrument. These include comprehension, planning, visuoconstruction abilities, motor programming, numerical knowledge, abstract thinking, and concentration.

There are several different tests that are used. One test, using a predrawn circle is standard for some, whereas others use a requirement for the subject to draw the circle. In typical case, subjects are given a circle and asked to place the hands at ten minutes past eleven.

In the Boston Diagnostic Aphasia battery, subjects are given four predrawn clocks, with ticks for the hours and asked to mark each clock to a different time: 1:00, 3:00. 9:15 and 11:30. One point is awarded for placing the hands in correct place, another for correct hand lengths, with three points per clock and maximum twelve points for entire test.

Shulman used a five point scale, with five points for a perfect clock, four for minor visuospatial errors, three for inaccurate representation of 10 minutes past eleven with visuospatial organization is well done, two for disorganized visuospatia representation such that telling ten minutes past eleven is immpossible, and one for inability to discern a clock.

Shulman cited roughly 85 % sensitivity and specificity, noting that the Clock Drawing Test adds frontal, visuospatial constructive ability to MMSE.

The CLOX test is a modified test used in CERAD. The subject is given a blank paper, and told "Draw me a clock and set the hands to 1:45 so that even a child could read them." That is CLOX 1. CLOX 2 the subject is given the clock and told to copy it. On Clox 1, subjects are graded as normal, mildly, moderately, or severely immpaired.

Tests can be used in a variety of settings that are not at first blush apparent, including screening patients undergoing hip replacement surgery for postop delirium, (better than MMSE)or subtyping dementia. Curiously, vascular dementia patients make more segmentation errors on clock test than do Alzheimer's patients.

Sunday, November 22, 2009

Dysfluency pearls: Stuttering, cluttering & palilalia


1. Developmental stuttering usually is made better by singing, repetitive reading of same passage (adaptation) and playing white noice in patient's own ear to prevent him from hearing his own speech . There is no neurologic lesion or evaluatin required.

2. Acquired stuttering can occur with multiple location small brain lesions and does require MRI. Unlike developmental stutterers, acquired stutterers are dysfluent throughout a sentence, not just at the beginning, and are generally not bothered or embarassed by the deficiency.

3. Cluttering is characterized by rapid speech, repetitions, omissions, interjections and disturbed prosody. Sounds and syllables may be inverted or omitted. Clutterers may repeat initia sounds and prolong sounds within the word. Clutterers are not concerned about the problem and usually do not need neurologic evaluation.

4. Palilalia is characterized by compulsive repetition of words and phrases at increasing speed and with a decrescendo phonatory volume, and occurs in Parkinson's disease and pseudobulbar palsy. It improves considerably when the patient speaks with a metronome.

Saturday, November 21, 2009

Akinetopsia in posterior cortical variant of Alzheimer's

Akinetopsia is inability to perceive motion (Zeki, Brain 1991). It occurs due to bilateral lesions at posterior parieto-occipital junction. (Also see Rizzo, Brain Res., 2008). Authors (Tsai and Mendez, Neurology 2009) report 2 patients with degenerative disease that reported double vision with vision as "a series of successive stills" from moving images. Neuropsych testing showed impaired constructions of figures (Rey-Ost.), impaired figure-ground, visual synthesis, search, depth discrimination Akinetopsia was elicited with vision to LEFT and not relieved with alternate eye cover/uncover. Laterality and preference for one lateralization corresponds with primate work.