Prism adaptation in patients with unilateral lesion of the parietal or cerebellar cortex: A pilot study on two single cases using a concurrent exposure procedure.

Neuroimaging studies showed that prism adaptation (PA), a widely used tool for the rehabilitation of neglect, involves a wide network of brain regions including the parietal cortex and the cerebellum. In particular, the parietal cortex has been suggested to mediate the initial stage of PA through conscious compensatory mechanisms as a reaction to the deviation induced by PA. The cerebellum, on the other side, intervenes in sensory errors prediction to update internal models in later stages. It has been suggested that two mechanisms may underlie PA effects: recalibration, a strategic cognitive process occurring in the initial stages of PA, and realignment, a fully automatic reorganization of spatial maps emerging later and more slowly in time. The parietal lobe has been proposed to be involved mainly in the recalibration whereas the realignment would be carried over by the cerebellum. Previous studies have investigated the effects of a lesion involving either the cerebellum or the parietal lobe in PA taking into account both realignment and recalibration processes. Conversely, no studies have compared the performance of a patient with a cerebellar lesion to that of a patient with a parietal lesion. In the present study, we used a recently developed technique for digital PA to test for differences in visuomotor learning after a single session of PA in a patient with parietal and a patient with cerebellar lesions, respectively. The PA procedure, in this case, includes a digital pointing task based on a concurrent exposure technique, which allows patients to fully see their arm during the pointing task. This procedure has been shown to be as effective as the terminal exposure condition in neglect rehabilitation albeit different processes take place during concurrent exposure condition compared to the most used terminal exposure (allowing to see only the final part of the movement). Patients' performances were compared to that of a control group. A single session of PA was administered to 1) a patient (BC) with left parieto-occipital lesion involving superior parietal lobe (SPL) and inferior parietal lobe (IPL), 2) a patient (TGM) with a stroke in the territory sub-served by the superior cerebellar artery (SCA) , and 3) 14 healthy controls (HC). The task included three conditions: before wearing prismatic goggles (pre-exposure), while wearing prisms (exposure) and after removing the goggles (post-exposure). Mean deviations were calculated for the following phases: pre-exposure, early-exposure, late-exposure, post-exposure. The presence of after-effect was calculated as the difference between pre-exposure and post-exposure conditions. For each of these conditions, patients' performance was compared to that of the control group by using a modified Crawford t-test. We found that the patient with the parietal lesion had a significantly different performance in the late-exposure and in the post-exposure compared to both HC and the patient with the cerebellar lesion. Conversely, no differences were observed between TGM and HC across all the conditions. Our results show an increase in the magnitude of the adaptation during the late stage of PA in the patient with the parietal lesion whereas no differences in the performance between the cerebellar patient and the controls were found. These results confirm previous studies suggesting that the parietal cortex is an important node of a wider network involved in PA effect. Furthermore, results concerning the cerebellar patient suggest that visuomotor learning is not affected by lesions of the SCA territory when a concurrent exposure is used as, in such case, it less relies on sensory errors prediction to update internal models. Results are discussed considering the novelty of the applied PA technique.

A questionnaire to collect unintended effects of transcranial magnetic stimulation: A consensus based approach.

Transcranial magnetic stimulation (TMS) has been widely used in both clinical and research practice. However, TMS might induce unintended sensations and undesired effects as well as serious adverse effects. To date, no shared forms are available to report such unintended effects. This study aimed at developing a questionnaire enabling reporting of TMS unintended effects. A Delphi procedure was applied which allowed consensus among TMS experts. A steering committee nominated a number of experts to be involved in the Delphi procedure. Three rounds were conducted before reaching a consensus. Afterwards, the questionnaire was publicized on the International Federation of Clinical Neurophysiology website to collect further suggestions by the wider scientific community. A last Delphi round was then conducted to obtain consensus on the suggestions collected during the publicization and integrate them in the questionnaire. The procedure resulted in a questionnaire, that is the TMSens_Q, applicable in clinical and research settings. Routine use of the structured TMS questionnaire and standard reporting of unintended TMS effects will help to monitor the safety of TMS, particularly when applying new protocols. It will also improve the quality of data collection as well as the interpretation of experimental findings.

Numerical activities of daily living in adults with neurofibromatosis type 1.

BACKGROUND: This study aimed to identify the mathematical domains affected in adults with neurofibromatosis 1 (NF1) and the impact of the numerical difficulties on the patients' activities of daily living. METHODS: We assessed 28 adult patients with NF1 and 28 healthy control participants. All participants completed the standardised battery of numerical activities of daily living along with clinical batteries of cognitive (Mini-Mental State Examination) and daily functioning (instrumental activities of daily living). The group comparisons of the performance on numerical activities of daily living were carried out using t-test correcting for multiple comparisons. RESULTS: The results showed that the NF1 group performed worse than controls in written subtractions, written multiplication, multiplication principles and digit comprehension (dot counting) tasks. Importantly, no significant differences in numerical ecological tasks were found between patients and controls, suggesting a possible use of compensatory strategies in daily living abilities in spite of calculation deficits. CONCLUSION: The findings indicate that NF1 affects calculation but not the basic comprehension or representation of numbers in adult patients. These data have important implications for designing cognitive interventions tailored to the cognitive profile of individuals with NF1.

Re-assessing acalculia: Distinguishing spatial and purely arithmetical deficits in right-hemisphere damaged patients.

Arithmetical deficits in right-hemisphere damaged patients have been traditionally considered secondary to visuo-spatial impairments, although the exact relationship between the two deficits has rarely been assessed. The present study implemented a voxelwise lesion analysis among 30 right-hemisphere damaged patients and a controlled, matched-sample, cross-sectional analysis with 35 cognitively normal controls regressing three composite cognitive measures on standardized numerical measures. The results showed that patients and controls significantly differ in Number comprehension, Transcoding, and Written operations, particularly subtractions and multiplications. The percentage of patients performing below the cutoffs ranged between 27% and 47% across these tasks. Spatial errors were associated with extensive lesions in fronto-temporo-parietal regions -which frequently lead to neglect- whereas pure arithmetical errors appeared related to more confined lesions in the right angular gyrus and its proximity. Stepwise regression models consistently revealed that spatial errors were primarily predicted by composite measures of visuo-spatial attention/neglect and representational abilities. Conversely, specific errors of arithmetic nature linked to representational abilities only. Crucially, the proportion of arithmetical errors (ranging from 65% to 100% across tasks) was higher than that of spatial ones. These findings thus suggest that unilateral right hemisphere lesions can directly affect core numerical/arithmetical processes, and that right-hemisphere acalculia is not only ascribable to visuo-spatial deficits as traditionally thought.

Aphasia burden to hospitalised acute stroke patients: need for an early rehabilitation programme.

BACKGROUND/PURPOSE: The aim of our study is to evaluate the frequency of aphasia and to describe the characteristics of aphasics among a large sample of acute stroke patients in Italy. METHODS: Out of the 11 572 stroke patients hospitalised within 48 h from stroke onset, included in the PROSIT study, we selected 9594 alert cases for the estimation of aphasia frequency. The presence of aphasia was accepted when registered in the clinical records at the first neurological examination. All patients/caregivers underwent to a 2-year telephone follow-up evaluation. RESULTS: Twenty-eight per cent of alert acute stroke patients had aphasia, which was associated with arm and/or limb weakness in 74% of cases. In our series, aphasia was more frequent in females than males, in patients older than 75 years and was associated with more severe stroke. Aphasics, compared with nonaphasics, died more frequently. Aphasia was also significantly associated with residual poststroke disability. CONCLUSIONS: This is the first study considering the frequency of aphasia in a wide population of hospitalised acute stroke patients. The presence of aphasia is more common in patients with severe stroke and contributes to residual disability. Our findings should be considered for setting early specific rehabilitation programmes.

The natural course of acalculia in left-brain-damaged patients.

Acalculia is a frequent disorder in left-brain-damaged patients but nothing is known about its natural course. We report a study on 51 vascular acalculic patients examined at least twice. Our results indicate that recovery from acalculia is possible in the first months post-stroke, that initial severity does not significantly influence recovery, and that it correlates with recovery of auditory comprehension.

Acalculia, aphasia and spatial disorders in left and right brain-damaged patients.

The paper reports the performance of 50 left- and 26 vascular right-brain-damaged (LBD, RBD) patients in the EC301 Calculation Battery, which explores different aspects of number and calculation processing. All patients underwent a comprehensive neuropsychological testing that also included evaluation for the presence and type of aphasia in LBD patients, and of spatial disorders in RBD patients. LBD were subdivided in three groups: non-aphasic (NA), Broca and Wernicke aphasics. Results indicate that language and calculation disorders can dissociate. The relationship between spatial and calculation disorders in RBD patients is less clear. No significant difference was found between Broca and Wernicke aphasics, nor between NA and RBD patients. In the transcoding tasks (reading or writing to dictation numbers and number words, for instance) syntactic errors were the most frequent type of errors in all groups. They were also present when neither the input nor the required response was in the Arabic code, and a word-by-word strategy could have been used to read the number word or write a spoken number in the orthographic code.

Acquisition of output irregular orthographic representations in normal adults: an experimental study.

Twenty normal controls without previous knowledge of French were asked to learn 12 French words that could not be written by Italian correspondence rules. After acquisition of the phonological representations, participants were presented the pictures and asked to write the corresponding words (baseline). They were then presented 3 times with the pictures and the corresponding written words. After a filled delay of 10 min, they were re-presented the pictures and asked to write the corresponding words (testing). A week later, participants were again requested to write the words (follow-up). Number of words correctly written at testing and at follow-up significantly differs from baseline, as well as number of words correctly written at testing and at follow-up. These results are discussed and it is suggested that acquisition of irregular output orthographic representations can be supported by knowledge of orthographic representations for reading and that rehabilitation of patients with damage to output orthographic representations can utilize input orthographic representations.

Memory and aphasia.

Sixty-one acute and 17 chronic vascular left-hemisphere damaged patients were tested with five memory tasks that investigated verbal short-term (digit span) and long-term (paired-associate and story learning) memory, and spatial short- and long-term memory (Corsi's span and learning). Both brain-damaged groups were significantly impaired in all memory tasks (except for chronic patients in the story learning task) compared to normal controls. The presence of aphasia and locus of lesion (anterior, posterior and deep) had no effect on the memory impairment, with only one exception of paired-associate learning that was better performed by non-aphasic than aphasic patients. Eleven subjects were better at paired-associate learning than story recall, the reverse dissociation was never found. Finally, chronic patients performed significantly better than acute patients only in the Corsi's learning task.

Cyclic vomiting and recurrent abdominal pains as migraine or epileptic equivalents.

A retrospective method was used to estimate the incidence of recurring motion-sickness, cyclic vomiting and abdominal pain considered as different manifestations of a so-called periodic syndrome in 100 migraine sufferers, 100 epileptics and 100 control subjects in the pediatric age group. Such recurrent symptoms are significantly more frequent in those suffering from migraine than in the other two groups. Examination of subgroups of patients affected by particular forms of migraine (classical and common) and of epilepsy (generalized seizures, simple partial seizures, complex partial seizures) contributed little new to our understanding of the nature of periodic syndrome. It is concluded that the above symptoms of periodic syndrome should generally be considered as manifestations of a migrainous rather than of an epileptic disorder.

Cerebrospinal fluid IgG changes in subacute sclerosing panencephalitis in the various stages of the disease and during isoprinosine therapy.

The cerebrospinal fluid (CSF) levels of IgG and the separation of the CSF and serum proteins by isoelectric focusing (IEF) were studied in 5 patients with subacute sclerosing panencephalitis (SSPE). Oligoclonal IgG fractions were found in the CSF of all the patients. The CSF IgG, IgG-Index and IgG SYN values were higher in the patients observed in the earlier than in those seen in the later stages of the disease. 1 of the 3 patients treated with isoprinosine presented a partial clinical remission accompanied by an increase in the parameters of intrathecal IgG synthesis.

[Progressive spinal amyotrophy. Nosographic problems]. / Le amiotrofie spinali progressive. Problemi nosografici

After a bibliographical revue on progressive spinal amyotrophy the nosographical aspects of the various forms are discussed, above all the proximal ones. Considering personal observations, the conclusion is that a definite differences is the various forms of proximal spinal amyotrophy does not exist and today they are different expressions of the same illness.