Behavioural Neurology - Volume 20, issue 3-4

Authors: Bekinschtein, Tristan A. | Cardozo, Julian | Manes, Facundo F.

Article Type: Research Article

Abstract: Human learning and memory evaluation in real-life situations remains difficult due to uncontrolled variables. Buenos Aires waiters, who memorize all the orders without written support, were evaluated in situ. Waiters received either eight different orders and customers remained seated in their original locations (OL), or changed locations (CL). Match between orders, subjects and location was decreased only in CL. Waiters' feature/location strategy links client with position at the table and beverage later. The …hypothesis we raise is that memory-schemas link working memory to long-term memory networks through rapid encoding, making the information resistant to interference and enabling its fast retrieval if necessary cues are present. Show more

Keywords: Memory, real-life, expertise

DOI: 10.3233/BEN-2008-0214

Citation: Behavioural Neurology, vol. 20, no. 3-4, pp. 65-70, 2008

Authors: Simon-Dack, Stephanie L. | Rodriguez, P. Dennis | Teder-Sälejärvi, Wolfgang A.

Article Type: Research Article

Abstract: Imaging, transcranial magnetic stimulation, and psychophysiological recordings of the congenitally blind have confirmed functional activation of the visual cortex but have not extensively explained the functional significance of these activation patterns in detail. This review systematically examines research on the role of the visual cortex in processing spatial and non-visual information, highlighting research on individuals with early and late onset blindness. Here, we concentrate on the methods utilized in studying visual cortical …activation in early blind participants, including positron emissions tomography (PET), functional magnetic resonance imaging (fMRI), transcranial magnetic stimulation (TMS), and electrophysiological data, specifically event-related potentials (ERPs). This paper summarizes and discusses findings of these studies. We hypothesize how mechanisms of cortical plasticity are expressed in congenitally in comparison to adventitiously blind and short-term visually deprived sighted participants and discuss potential approaches for further investigation of these mechanisms in future research. Show more

Keywords: Visual function, plasticity, blind, brain imaging, EEG, ERP, fMRI, PET, TMS

DOI: 10.3233/BEN-2008-0217

Citation: Behavioural Neurology, vol. 20, no. 3-4, pp. 71-81, 2008

Authors: Hoffmann, Michael

Article Type: Research Article

Abstract: Background: Right temporal lobe lesion syndrome elicitation presents a clinical challenge. Aside from occasional covert quadrantanopias, heralding elementary neurological deficits are absent. Aim: Isolated right and left temporal lobe stroke patients were analyzed for the panoply of known temporal and frontal cognitive and neuropsychiatric syndromes. Methods: Temporal lobe stroke patients were analyzed, derived from a dedicated cognitive stroke registry. Patients were screened by a validated bedside cognitive battery and a neuropsychological test battery, …including the Bear Fedio Inventory for diagnosis of the Geschwind Gastaut (GG) syndrome, frontal network syndrome testing (FNS), emotional intelligence testing and delusional misidentification syndromes (DMIS). NIH stroke scores were documented and lesion location identified with the 3 dimensional digitized Cerefy coxial brain atlas. Exclusions were coma, encephalopathy and medication related effects. Results: Of 2389 patients analyzed, in patients with isolated right temporal lobe (IRT) stroke (n = 5, infarcts n = 3, hemorrhage n = 2), the GG syndrome and FNS were present in all five. Other relatively frequent syndromes included DMIS in 4, visuospatial dysfunction in 2 and amusia in 2. No patient had a NIHSS greater than 1. The only elementary neurological sign was quadrantanopia in 3 patients. Lesion location was mid and lateral temporal lobe (n = 2), middle and mesial temporal lobe (n = 1) middle temporal lobe (n = 1) and lateral temporal lobe (n = 1). Comparison with isolated left temporal lobe (ILT) stroke revealed syndromes of aphasia (n = 4), alexia (n = 2), acalculia (n = 2), agnosia (n = 2), verbal amnesia (n = 1), none of which occurred in the IRT patients. The mean NIHSS scores of IRT (0.6) and ILT strokes (4.2) was different (t = 2.23, p = 0.04). The 2 × 8 Fisher Exact Test revealed significant differences for the clusters of syndromes occurring in the right and left isolated temporal lobe lesions (p = 0.00002). Conclusion: The GG syndrome, FNS and DMIS are prominent syndrome constellations in stroke patients involving the right temporal lobe and constitute the neurological deficit without heralding long tract signs. By extrapolation these syndromes may also be present in the general right hemisphere lesion population. Show more

DOI: 10.3233/BEN-2008-0218

Citation: Behavioural Neurology, vol. 20, no. 3-4, pp. 83-89, 2008

Authors: Ichikawa, Hiroo | Takahashi, Nobuyoshi | Hieda, Soutaro | Ohno, Hideki | Kawamura, Mitsuru

Article Type: Research Article

Abstract: The clinical significance and characteristics of writing errors in bulbar-onset amyotrophic lateral sclerosis (ALS) are not clear. We retrospectively investigated writing samples in 19 patients with bulbar-onset ALS without preceding extra-motor symptoms. Co-development of dementia and/or aphasia was also explored and single photon emission computed tomography (SPECT) images of the brain were reviewed. As a result, a high prevalence of writing errors (15 of the 19 patients) was found. Of note were isolated writing …errors with neither dementia nor aphasia verified in 2 patients whose dysarthria was mild enough to evaluate spoken language. The remaining 13 patients also showed agraphia, but either dysarthria was too severe to evaluate aphasia or frontotemporal dementia (FTD)-like features co-existed. Of these patients, one who initially lacked dementia subsequently developed FTD-like features. The frequent writing errors were omission or substitution of kana letters and syntactic errors. SPECT images showed bilateral or left-side dominant hypoperfusion in the frontotemporal lobes as a consistent feature. These results show that patients with bulbar-onset ALS frequently exhibit agraphic writing errors and that these are not merely consequences of dementia or aphasia. However, these writing errors may indicate the involvement of frontotemporal language-related areas beyond the primary motor cortex. Show more

Keywords: Amyotrophic lateral sclerosis, writing error, agraphia, syntactic error, frontotemporal dementia

DOI: 10.3233/BEN-2008-0219

Citation: Behavioural Neurology, vol. 20, no. 3-4, pp. 91-99, 2008

Authors: Hoffmann, Michael | Cases, Lourdes Benes

Article Type: Research Article

Abstract: Background: The neurobiology of the frontal network syndrome (FNS) that may occur with isolated subtentorial stroke is unknown. Aim: Evaluate for frontal network syndromes in young people post subtentorial stroke who have recovered neurologically and compare to a stroke lesion group least likely to manifest frontal network syndromes. Methods: Young people (18–49 years) with isolated cerebellar or brainstem subtentorial stroke (ST) that had recovered to independency (Rankin score ⩽ 2) with minimal or no residual neurological deficit …(NIHSS ⩽ 4) with neurological recovery enabling resumption of former employment. Comparison was made to age and education matched young people with posterior circulation territory parieto occipital lobe infarcts (PO). Depression, anxiety, systemic disease, autoimmune disease, neurodegenerative disease and substance abuse were specific exclusions. A battery of frontal tests surveying the principal frontal network syndromes (apathy, disinhibition, executive dysfunction, emotional intelligence quotient) was used. Neurological deficit and long tract signs were measured by the NIH stroke score (NIHSS). Results: From the cognitive stroke registry of young stroke patients (n = 511), analysis for isolated subtentorial infarction yielded cerebellar infarcts (n = 43, 8.4%) and brainstem infarcts (n = 36, 7.0%). After exclusions, 16 patients (cerebellum, n = 10, pons, n = 6) were compared to 10 PO infarct patients controlled for mean age, gender and NIH stroke scores. Overall 11/16 (69%) patients in the ST and 5/10 (50%) in the PO group manifested one or more of the principal FNS syndromes. Mean T scores for apathy, disinhibition, executive function and emotional intelligence standard scores were significantly more impaired in the ST group, but not for WCST error percentage scores. Conclusions: The mismatch of scant neurological deficit manifested by low NIHSS but with FNS in the majority of isolated ST stroke and more so than with PO stroke, gives support for a state dependent or neurotransmitter perturbation. The clinical impact is that such syndromes may be amenable to neuropharmacological intervention. Show more

DOI: 10.3233/BEN-2008-0220

Citation: Behavioural Neurology, vol. 20, no. 3-4, pp. 101-105, 2008

Authors: Ghanizadeh, Ahmad

Article Type: Research Article

Abstract: Objectives: While a group of children with ADHD may have normal behavioral responses to sensory stimuli, another group may be hyperreactive. The aim of this survey was studying association of tactile sensory responsivity with co-morbidity of oppositional defiant disorder (ODD) symptoms, subtypes of ADHD, and gender in children with ADHD. Methods: The subjects were 81 children with ADHD from a child psychiatry clinic. The diagnoses were made according to DSM-IV diagnostic criteria. Tactile dysfunction …Checklist was used to assess the three types of tactile sensory dysfunction including Hypersensitivity, hyposensitivity, and poor tactile perception and discrimination (PTPD). Results: Their mean age was 8.4 (SD = 1.9) years. None of the gender, number of symptoms of ODD co-morbidity, and ADHD subtypes was as a predictor of scores of Hyposensitivity and PTPD subscales. Tactile defensiveness was not different between genders and different subtypes of ADHD. Conclusions: Number of ODD symptoms in children with ADHD is a predictor in association with hypersensitivity score of tactile sensory function. Girls are no more than the boys impaired in Hypersensitivity aspect. Different subtypes of ADHD are not distinct disorders regarding to tactile sensory function. Show more

Keywords: ADHD, ODD, Tactile sensory dysfunction, children, gender, checklist

DOI: 10.3233/BEN-2008-0221

Citation: Behavioural Neurology, vol. 20, no. 3-4, pp. 107-112, 2008

Authors: Stracciari, Andrea | Fonti, Cristina | Guarino, Maria

Article Type: Research Article

Abstract: We report the clinical findings and neuropsychological profiles of a sample of patients exhibiting a focal retrograde amnesia (FRA) seen consecutively during the period 1992–2007. The cohort comprised 13 patients, five males, with a mean age of 30 years (range 16–49). They were given a neurologic examination, psychiatric interview and formal neuropsychological examination (all but one) during the amnesic phase, underwent neuroimaging, and were followed up for six months to ten years. All presented with an …acute amnesia characterized by an impaired recollection of memories predating the acute event, with spared or minimally and transiently affected anterograde memory, thus consistent with FRA. The events triggering FRA varied widely: mild to severe head injury, road accident without head injury, seizure, dissociative fugue, BDZ overdose, posttraumatic headache, syncope, migraine attack, acute distress. The neuropsychological hallmark of FRA was a selective or prominent impairment of autobiographical memory. The defect was often so severe as to cover most or all of the patients' lives and, in some cases, to erase the knowledge of their own identity. Conventional neuroimaging (brain CT and MRI) was unimpressive. Cerebral SPECT/PET disclosed unilateral frontal hypoperfusion in three (two left). All but one patient fully recovered, time of recovery ranging from three days to six months. FRA is a condition reflecting a block of memory function triggered by heterogeneous events, including both physical and psychic insults. Analogies shared with the more frequently encountered and better known condition of transient global amnesia suggests common pathogenetic mechanisms. A tentative nosographic classification of FRA is finally offered. Show more

Keywords: Amnesia, focal retrograde amnesia, psychogenic amnesia, functional amnesia, transient global amnesia

DOI: 10.3233/BEN-2008-0222

Citation: Behavioural Neurology, vol. 20, no. 3-4, pp. 113-125, 2008

Authors: Allen, Mark D. | Fong, Alina K.

Article Type: Research Article

Abstract: Functional MRI is increasingly recognized for its potential as a powerful new tool in clinical neuropsychology. This is likely due to the fact that, with some degree of innovation, it is possible to convert practically any familiar cognitive test into one that can be performed in the MRI scanning environment. However, like any assessment approach, meaningful interpretation of fMRI data for the purpose of patient evaluation crucially requires normative data derived from a sample of unimpaired …persons, against which individual patients may be compared. Currently, no such normative data are available for any fMRI-based cognitive testing protocol. In this paper, we report the first of a series of fMRI-compatible cognitive assessment protocols, a matrix reasoning test (f-MRT), for which normative samples of functional activation have been collected from unimpaired control subjects and structured in a manner that makes individual patient evaluation possible in terms of familiar z-score distributions. Practical application of the f-MRT is demonstrated via a contrastive case-study of two individuals with cognitive impairment in which fMRI data identifies subtleties in patient deficits otherwise missed by conventional measures of performance. Show more

Keywords: fMRI, matrix reasoning, cognitive assessment, normative data

DOI: 10.3233/BEN-2008-0223

Citation: Behavioural Neurology, vol. 20, no. 3-4, pp. 127-140, 2008

Authors: Allen, Mark D. | Fong, Alina K.

Article Type: Research Article

Abstract: In this study, we describe an fMRI version of the verbal fluency test. This is the second in a series of fMRI adaptations of classical neuropsychological tests, for which normative samples of functional activation have been collected from unimpaired control subjects and structured in a manner that makes individual patient evaluation possible in terms of familiar z-score distributions. This fMRI protocol is shown to have strong convergent validity with the FAS phonemic fluency test and to …elicit activation patterns highly consistent with a large body of previous neuroimaging studies of verbal fluency. We also present a case study, in which we report concurrent data from a patient with selective deficits in verbal processing, using both conventional neuropsychological and fMRI approaches. These analyses reveal striking correspondences between the deficits present in this patient on cognitive performance tests and the equally selective patterns of deviation present in his fMRI data. Show more

Keywords: fMRI, verbal fluency, cognitive assessment, normative data

DOI: 10.3233/BEN-2008-0224

Citation: Behavioural Neurology, vol. 20, no. 3-4, pp. 141-152, 2008