Left neglect dyslexia: Perseveration and reading error types.

Right-brain-damaged patients may show a reading disorder termed neglect dyslexia. Patients with left neglect dyslexia omit letters on the left-hand-side (the beginning, when reading left-to-right) part of the letter string, substitute them with other letters, and add letters to the left of the string. The aim of this study was to investigate the pattern of association, if any, between error types in patients with left neglect dyslexia and recurrent perseveration (a productive visuo-motor deficit characterized by addition of marks) in target cancellation. Specifically, we aimed at assessing whether different productive symptoms (relative to the reading and the visuo-motor domains) could be associated in patients with left spatial neglect. Fifty-four right-brain-damaged patients took part in the study: 50 out of the 54 patients showed left spatial neglect, with 27 of them also exhibiting left neglect dyslexia. Neglect dyslexic patients who showed perseveration produced mainly substitution neglect errors in reading. Conversely, omissions were the prevailing reading error pattern in neglect dyslexic patients without perseveration. Addition reading errors were much infrequent. Different functional pathological mechanisms may underlie omission and substitution reading errors committed by right-brain-damaged patients with left neglect dyslexia. One such mechanism, involving the defective stopping of inappropriate responses, may contribute to both recurrent perseveration in target cancellation, and substitution errors in reading. Productive pathological phenomena, together with deficits of spatial attention to events taking place on the left-hand-side of space, shape the manifestations of neglect dyslexia, and, more generally, of spatial neglect.

(Un)awareness of unilateral spatial neglect: a quantitative evaluation of performance in visuo-spatial tasks.

Right-brain-damaged patients with unilateral spatial neglect are usually unaware (anosognosic) about their spatial deficits. However, in the scientific literature there is a lack of systematic and quantitative evaluation of this kind of unawareness, despite the negative impact of anosognosia on rehabilitation programs. This study investigated anosognosia for neglect-related impairments at different clinical tasks, by means of a quantitative assessment. Patients were tested in two different conditions (before and after execution of each task), in order to evaluate changes in the level of awareness of neglect-related behaviours triggered by task execution. Twenty-nine right-brain-damaged patients (17 with left spatial neglect) and 27 neurologically unimpaired controls entered the study. Anosognosia for spatial deficits is not pervasive, with different tasks evoking different degrees of awareness about neglect symptoms. Indeed, patients showed a largely preserved awareness about their performance in complex visuo-motor spatial and reading tasks; conversely, they were impaired in evaluating their spatial difficulties in line bisection and drawing from memory, showing over-estimation of their performance. The selectivity of the patients' unawareness of specific manifestations of spatial neglect is further supported by their preserved awareness of performance at a linguistic task, and by the absence of anosognosia for hemiplegia. This evidence indicates that discrete processes are involved in the aware monitoring of cognitive and motor performance, which can be selectively compromised by brain damage. Awareness of spatial difficulties is supported by a number of distinct components, and influenced by the specific skills required to perform a given task.

Memantine in Alzheimer's disease: experience in an Alzheimer's disease assessment unit.

BACKGROUND AND AIMS: Memantine is an uncompetitive N-methyl-D-aspartate receptor antagonist. Clinical and observational studies have demonstrated its efficacy on both cognitive and behavioral symptoms of moderate-to-severe Alzheimer's disease (AD) and described its good safety and tolerability profile. We report here our experience with memantine in patients with AD during a two-year follow-up. METHODS: From June 2005 to May 2010, memantine was given to 201 outpatients with moderate-to-severe AD: 93 patients were concomitantly receiving treatment with acetyl cholinesterase inhibitors (AChEIs) (Group 1) and the other 108 were prescribed memantine as monotherapy (Group 2). All patients were administered the following scales: Mini Mental State Examination, Activities of Daily Living, Instrumental Activities of Daily Living, Neuropsychiatric Inventory. We report the results of followup assessments conducted at six months and 1, 2 and 3 years. RESULTS: Sixteen patients (8%) stopped treatment within the first month because of side-effects. In each group, about 20% of subjects showed no deterioration at six months and 1 year, and this proportion decreased only slightly at 2 years. Higher NPI scores at baseline and psychotropic drug use emerged as factors significantly related to reduced response to treatment (p<0.01). CONCLUSIONS: Results confirmed the short-term effect of memantine, both in monotherapy and in combination with AchEIs in moderate-to-severe AD. This efficacy, albeit slight, was found to persist in the longer term.

Spatial neglect and perseveration in visuomotor exploration.

OBJECTIVE: Right-brain-damaged patients with left spatial neglect make perseveration errors in target cancellation tasks. A recent study (Ronchi, Posteraro, Fortis, Bricolo, & Vallar, 2009) showed that perseveration occurred more frequently in star than in letter cancellation, possibly due to different stimulus disposition. In this study we investigated the role of the spatial organization of targets (scattered vs. arranged) of the star and letter cancellation tasks in eliciting omission and perseveration errors; the role of impairments of divided attentional resources; and the lesion correlates of perseveration. METHOD: Thirty-three right-brain-damaged patients (27 with neglect, and six without neglect; 17 showing perseveration, 16 of them with spatial neglect) were given two versions of the star and letter cancellation tasks (with stimuli scattered or in rows), and a dual task. RESULTS: A scattered target disposition increased omission and perseveration errors. Target type modulated differently omission and perseveration, with the former being more elicited by verbal targets, and the latter occurring more frequently in the star cancellation task, with scattered stimuli. Perseveration behavior was unrelated to deficits of divided attention, as assessed by the dual task. Lesion analysis indicated damage to the right insula as a neural correlate of perseveration. CONCLUSIONS: A display including nonverbal (star) and scattered targets brings about more perseveration errors. Target type and organization modulate in a different fashion omission and perseveration, suggesting the involvement of independent pathological mechanisms, which, however, do not implicate deficits of divided attention. The role of insular damage in motor perseveration in spatial neglect is discussed.

Caregiver burden and coping in early-stage Alzheimer disease.

This study was set out to describe caregiver-perceived burden and coping in early-stage Alzheimer disease (AD). A total of 163 consecutive pairs of patients with AD and their principal caregivers were initially recruited. The caregivers completed the Caregiver Burden Inventory (CBI) and the Coping Orientations to Problems Experienced scale, and also provided sociodemographic information; the patients with AD were assessed by means of the Mini Mental State Examination and the Neuropsychiatric Inventory. Data from 126 patient-caregiver pairs were analyzed. The caregivers (mean age 56.11±12.37 y) were mainly women (76%); 64% were the patient's offspring; 39% lived with the patient. From the CBI data, it emerged that caregivers perceived loss of personal time (objective burden, 33%) and the feeling of missing out on opportunities (developmental burden, 25%) as their main stressors. Total CBI score was negatively correlated with Mini Mental State Examination (P=0.005). As regards coping strategies, the caregivers predominantly used problem-oriented strategies associated with a positive attitude. The use of dysfunctional strategies was predictive of caregiver burden. It is important to be aware that avoidance and dysfunctional coping strategies predispose caregivers of patients with AD to higher level of distress, whereas successful caregiving seems to be based on the use of problem-oriented strategies early in the disease when solutions are still available.

Differences between physician and caregiver evaluations in Alzheimer's disease.

In Alzheimer's disease (AD) differences are often reported between caregivers' and physicians' aims and evaluations. The aim of this study was to investigate the presence of discrepancies between the evaluations of caregivers and physicians. Two hundred and eighteen caregivers of outpatients diagnosed with mild-to-moderate AD, referred to our Alzheimer's Disease Assessment Unit, entered the study. Caregiver burden was investigated using the Caregiver Burden Inventory (CBI) and the Neuropsychiatric Inventory Caregiver Distress Scale (NPIDS). Caregivers were also administered a four-point scale to assess quantitatively whether their expectations in relation to the efficacy of the pharmacological treatment had been satisfied and a scale exploring clinical global impression of change. Caregivers whose expectations had not been satisfied had significantly higher CBI and NPIDS scores and a lower level of education; moreover, caregivers tended to overestimate the degree of cognitive decline during the course of the disease. These results underline the importance of correct and constant communication with AD patients and their families.