White matter tract disconnection in Gerstmann's syndrome: Insights from a single case study

It has been suggested that Gerstmann's syndrome is the result of subcortical disconnection rather than emerging from damage of a multifunctional brain region within the parietal lobe. However, patterns of white matter tract disconnection following parietal damage have been barely investigated. This single case study allows characterising Gerstmann's syndrome in terms of disconnected networks. We report the case of a left parietal patient affected by Gerstmann's tetrad: agraphia, acalculia, left/right orientation problems, and finger agnosia. Lesion mapping, atlas-based estimation of probability of disconnection, and DTI-based tractography revealed that the lesion was mainly located in the superior parietal lobule, and it caused disruption of both intraparietal tracts passing through the inferior parietal lobule (e.g., tracts connecting the angular, supramarginal, postcentral gyri, and the superior parietal lobule) and fronto-parietal long tracts (e.g., the superior longitudinal fasciculus). The lesion site appears to be located more superiorly as compared to the cerebral regions shown active by other studies during tasks impaired in the syndrome, and it reached the subcortical area potentially critical in the emergence of the syndrome, as hypothesised in previous studies. Importantly, the reconstruction of tracts connecting regions within the parietal lobe indicates that this critical subcortical area is mainly crossed by white matter tracts connecting the angular gyrus and the superior parietal lobule. Taken together, these findings suggest that this case study might be considered as empirical evidence of Gerstmann's tetrad caused by disconnection of intraparietal white matter tracts.

Speech and Language Therapy for Acquired Central Dysgraphia in Neurological Patients: A Systematic Review to Describe and Identify Trainings for Clinical Practice

PURPOSE

Acquired central dysgraphia is a heterogeneous neurological disorder that usually co-occurs with other language disorders. Written language training is relevant to improve everyday skills and as a compensatory strategy to support limited oral communication. A systematic evaluation of existing writing treatments is thus needed.

METHOD

We performed a systematic review of speech and language therapies for acquired dysgraphia in studies of neurological diseases (PROSPERO: CRD42018084221), following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) checklist with a search on several databases for articles written in English and published until August 31, 2021. Only methodological well-designed studies were included. Further assessment of methodological quality was conducted by means of a modified version of the Downs and Black checklist.

RESULTS

Eleven studies of 43 patients in total were included. For each study, we collected data on type of population, type of impairment, experimental design, type of treatment, and measured outcomes. The studies had a medium level of assessed methodological quality. An informative description of treatments and linkages to deficits is reported.

CONCLUSIONS

Although there is a need for further experimental evidence, most treatments showed good applicability and improvement of written skills in patients with dysgraphia. Lexical treatments appear to be more frequently adopted and more flexible in improving dysgraphia and communication, especially when a multimodal approach is used. Finally, the reported description of treatment modalities for dysgraphia in relation to patients' deficits may be important for providing tailored therapies in clinical management.

Biofeedback as an Adjunctive Treatment for Post-stroke Dysphagia: A Pilot-Randomized Controlled Trial

BACKGROUND AND PURPOSE

Post-stroke dysphagia affects almost half of the survivors and severely influences quality of life, thus becoming swallowing rehabilitation of paramount importance. However, there is little adequate evidence on which the best rehabilitative strategy can be. Surface electromyography (sEMG) allows for recording swallowing muscles' activity and provides real time visual feedback, as a biofeedback adjunctive technique to improve treatment outcome. This study aimed to analyze the effectiveness of biofeedback rehabilitation of swallowing through sEMG compared to standard techniques, in post-stroke dysphagia.

METHODS

A pilot-randomized controlled trial included 17 patients diagnosed with post-stroke dysphagia. Nine underwent sEMG-biofeedback rehabilitation; seven controls were submitted to control treatment, one dropout. The primary outcome was the functional oral intake scale (FOIS), secondary outcomes was pharyngeal clearance and safe swallowing, assessed through fiberoptic endoscopic evaluation of swallowing (FEES).

RESULTS

FOIS improved in all patients, regardless of treatment. sEMG-biofeedback rehabilitation led to improvements of the pharyngeal clearance and swallowing safety. The rehabilitative effects appeared stable at 2-months follow-up.

CONCLUSIONS

The application of biofeedback based on sEMG in post-stroke dysphagia patients resulted in an effective rehabilitative technique, in particular for pharyngeal clearance improvements and safe swallowing, thus reducing the risk of aspiration and malnutrition.

Sensorimotor, Attentional, and Neuroanatomical Predictors of Upper Limb Motor Deficits and Rehabilitation Outcome after Stroke

The rehabilitation of motor deficits following stroke relies on both sensorimotor and cognitive abilities, thereby involving large-scale brain networks. However, few studies have investigated the integration between motor and cognitive domains, as well as its neuroanatomical basis. In this retrospective study, upper limb motor responsiveness to technology-based rehabilitation was examined in a sample of 29 stroke patients (18 with right and 11 with left brain damage). Pretreatment sensorimotor and attentional abilities were found to influence motor recovery. Training responsiveness increased as a function of the severity of motor deficits, whereas spared attentional abilities, especially visuospatial attention, supported motor improvements. Neuroanatomical analysis of structural lesions and white matter disconnections showed that the poststroke motor performance was associated with putamen, insula, corticospinal tract, and frontoparietal connectivity. Motor rehabilitation outcome was mainly associated with the superior longitudinal fasciculus and partial involvement of the corpus callosum. The latter findings support the hypothesis that motor recovery engages large-scale brain networks that involve cognitive abilities and provides insight into stroke rehabilitation strategies.

Recovery from tactile agnosia: a single case study

In a patient suffering from tactile agnosia a comparison was made (using the ABABAB paradigm) between three blocks of neuropsychological rehabilitation sessions involving off-line anodal transcranial direct current stimulation (anodal-tDCS) and three blocks of rehabilitation sessions without tDCS. During the blocks with anodal-tDCS, the stimulation was administered in counterbalanced order to two sites: i) the perilesional parietal area (specific stimulation) and ii) an occipital area far from the lesion (nonspecific stimulation).Rehabilitation associated with anodal-tDCS (in particular in the perilesional areas) is more efficacious than without stimulation.

Communicative and swallowing disorders in anoxic patients: A retrospective study on clinical outcomes and performance measures

BACKGROUND

Anoxic brain injury (ABI) is a neurological condition associated to a severe deterioration of brain functioning, whose symptomatology and clinical outcomes may be heterogeneous: cognitive deficits, language disorders like dysarthria and swallowing impairments. Nevertheless, there is still a lack of information on the rehabilitation outcomes.

OBJECTIVE

To confirm the occurrence of communication and swallowing deficits in 37 ABI patients and to examine whether intensive rehabilitation may contribute to any improvements and its relation to ABI severity and functional autonomy.

METHODS

37 patients, hospitalized at IRCCS San Camillo Hospital from 2011 to 2018 were analyzed retrospectively. All patients completed a functional evaluation and a language and swallowing assessment, within one week from hospital admission (T0). The assessment was repeated after an intensive rehabilitation treatment (T1).

RESULTS

Results show that dysphagia is a frequent and severe outcome in anoxic patients, whereas communication disorders (aphasia and dysarthria) are less severe. Moreover, ABI patients seem to be positively sensitive to an intensive rehabilitation program.

CONCLUSIONS

An early multidisciplinary management of communicative-linguistic and swallowing functions is crucial in order to prevent adverse events and to plan a tailored rehabilitation pathway.

Modulation of somatoparaphrenia following left-hemisphere damage

Somatoparaphrenic symptoms after left-hemisphere damage are rare. To verify the potential role of body-related sensory (proprioceptive, visual, and somatosensory) manipulation in patients experiencing sensations of hand disownership, the symptoms of a patient suffering from right-hand somatoparaphrenia were monitored and clinical and neuropsychological variables were controlled. Four types of manipulation were administered: changes in spatial position of the hand, multisensory stimulation, and self-observation using video or mirrors. Multisensory visuo-tactile stimulation was efficacious in terms of reducing somatoparaphrenia, and changes in the position of the hand produced some positive effects. Third-person perspective self-observation did not, however, result in any changes.