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Blindsight denotes unconscious residual visual capacities in the context of an inability to consciously recollect or identify visual information. It has been described for color and shape discrimination, movement or facial emotion recognition. The present study investigates a patient suffering from cortical blindness whilst maintaining select residual abilities in face detection. Our patient presented the capacity to distinguish between jumbled/normal faces, known/unknown faces or famous people's categories although he failed to explicitly recognize or describe them. Conversely, performance was at chance level when asked to categorize non-facial stimuli. Our results provide clinical evidence for the notion that some aspects of facial processing can occur without perceptual awareness, possibly using direct tracts from the thalamus to associative visual cortex, bypassing the primary visual cortex. [ABSTRACT FROM AUTHOR]

Semantic memory impairment is classically associated with lesion of the anterior temporal lobe. We report the case of a patient with severe semantic knowledge impairment and anterograde amnesia after bilateral ischemic lesion of the fornix and of the basal forebrain following surgical clipping of an aneurysm of the anterior communicating artery. Fluorodeoxyglucose positron emission tomography (FDG-PET) showed a temporal hypometabolism. Severe semantic impairment is a rare complication after rupture of an anterior communicating artery aneurysm and may result from disconnection of the temporal lobe. [ABSTRACT FROM AUTHOR]

Environmental reduplicative paramnesia (ERP) is characterized by the involuntary attribution of a false identity to a place. ERP has rarely been examined experimentally; its mechanisms therefore remain speculative. Here, we describe a patient with extended traumatic right fronto-temporal damage and severe persistent ERP, in whom we were able to modulate ERP by exposing him to various typical landmarks of the town where he was hospitalized. When landmarks were ambiguous as regards location (e.g., unknown buildings), the patient erroneously localized himself in his hometown, which was more than two thousand kilometers away. In contrast, when he visited distinct landmarks of the place where he actually resided, his ERP was immediately corrected, and spatial orientation was restored. These findings indicate that ERP may be temporarily modifiable through perception of unequivocal topographic information. [ABSTRACT FROM AUTHOR]

A 57-year-old man suffered severe amnesia and disorientation, accompanied by content-specific confabulation, due to an alcoholic Wernicke–Korsakoff syndrome. For months, he was deeply concerned about a single obligation that he thought he had to respond to, but which he had already assumed 20 years previously. This monothematic, prospective confabulation was associated with failures of reality filtering as previously documented in behaviorally spontaneous confabulation and disorientation: the patient failed to suppress the interference of currently irrelevant memories and to abandon anticipations that were no longer valid (impaired extinction capacity). Magnetic resonance imaging showed damage to the mamillary bodies and the dorsomedial thalamic nucleus. Positron emission tomography (FDG-PET) showed extended orbitofrontal hypometabolism. We suggest that isolated prospective confabulation shares the core feature (acts and thoughts based on currently irrelevant memory), mechanism (failure of reality filtering), and anatomical basis (orbitofrontal dysfunction) with behaviorally spontaneous confabulations. [ABSTRACT FROM AUTHOR]

Background. The effect of levodopa on recovery from aphasia is controversial. Objective. To determine whether levodopa enhances the effect of intensive computer-assisted therapy (CAT) of anomia in the postacute stage of aphasia. Methods. Double-blind multiple case study with intrasubject crossover design comparing the effect of levodopa (100 mg) versus placebo, each given for 2 weeks. Subjects. Twelve patients with onset of aphasia from 2 to 9 weeks after stroke or traumatic brain injury were compared on naming performance on items trained and not trained with CAT. Subjects were randomized to either levodopa or placebo first, separated by a 1-week washout, and then switched to the other drug intervention for the second 2-week CAT intervention. The subjects also received routine aphasia therapies during these periods. Results. All patients improved their naming performance for items trained by CAT in both periods (P = .001). No significant difference was found between the placebo and levodopa phases. Conclusion. Administration of levodopa for 2 weeks during the postacute stage of aphasia did not augment the positive effects of subacute intensive language treatment with CAT for a spoken naming task. [ABSTRACT FROM PUBLISHER]

Background: Disorientation and confabulation often have a common course, independent of amnesia. Behaviorally spontaneous confabulation is the form in which patients act according to a false concept of reality; they fail to abandon action plans (anticipations) that do not pertain to the present situation. This continued enactment of previously valid but meanwhile invalidated anticipations can be conceived as deficient extinction capacity, that is, failure to integrate negative prediction errors into behavior. In this study, we explored whether disorientation and behaviorally spontaneous confabulation are associated with extinction failure. Methods: Twenty-five patients hospitalized for neurorehabilitation after first-ever brain injury who either had severe amnesia (n = 17), an orbitofrontal lesion (n = 14), or both (n = 6) were tested regarding disorientation (questionnaire) and performed an experimental task of association learning and extinction. Five patients were also classified as behaviorally spontaneous confabulators. Results: Extinction capacity explained 66% of the variance of orientation in the whole group of patients (amnesics only, 56%; orbitofrontal group only, 90%), whereas association learning explained only 17% of the variance in the whole group (amnesics only, 7%; orbitofrontal group only, 16%). Also, extinction capacity, but not association learning, significantly distinguished between behaviorally spontaneous confabulators and all other subjects. Conclusions: Disorientation and behaviorally spontaneous confabulation are strongly and specifically associated with a failure of extinction, the ability to learn that previously appropriate anticipations no longer apply. Rather than invoking high-level monitoring processes, the human brain seems to make use of an ancient biological faculty—extinction—to keep thought and behavior in phase with reality. [Copyright &y& Elsevier]

Background: Stroke rehabilitation interventions are routinely personalized to address individuals' needs, goals, and challenges based on evidence from aggregated randomized controlled trials (RCT) data and meta-syntheses. Individual participant data (IPD) meta-analyses may better inform the development of precision rehabilitation approaches, quantifying treatment responses while adjusting for confounders and reducing ecological bias., Aim: We explored associations between speech and language therapy (SLT) interventions frequency (days/week), intensity (h/week), and dosage (total SLT-hours) and language outcomes for different age, sex, aphasia severity, and chronicity subgroups by undertaking prespecified subgroup network meta-analyses of the RELEASE database., Methods: MEDLINE, EMBASE, and trial registrations were systematically searched (inception-Sept2015) for RCTs, including ⩾ 10 IPD on stroke-related aphasia. We extracted demographic, stroke, aphasia, SLT, and risk of bias data. Overall-language ability, auditory comprehension, and functional communication outcomes were standardized. A one-stage, random effects, network meta-analysis approach filtered IPD into a single optimal model, examining SLT regimen and language recovery from baseline to first post-intervention follow-up, adjusting for covariates identified a-priori . Data were dichotomized by age (⩽/> 65 years), aphasia severity (mild-moderate/ moderate-severe based on language outcomes' median value), chronicity (⩽/> 3 months), and sex subgroups. We reported estimates of means and 95% confidence intervals. Where relative variance was high (> 50%), results were reported for completeness., Results: 959 IPD (25 RCTs) were analyzed. For working-age participants, greatest language gains from baseline occurred alongside moderate to high-intensity SLT (functional communication 3-to-4 h/week; overall-language and comprehension > 9 h/week); older participants' greatest gains occurred alongside low-intensity SLT (⩽ 2 h/week) except for auditory comprehension (> 9 h/week). For both age-groups, SLT-frequency and dosage associated with best language gains were similar. Participants ⩽ 3 months post-onset demonstrated greatest overall-language gains for SLT at low intensity/moderate dosage (⩽ 2 SLT-h/week; 20-to-50 h); for those > 3 months, post-stroke greatest gains were associated with moderate-intensity/high-dosage SLT (3-4 SLT-h/week; ⩾ 50 hours). For moderate-severe participants, 4 SLT-days/week conferred the greatest language gains across outcomes, with auditory comprehension gains only observed for ⩾ 4 SLT-days/week; mild-moderate participants' greatest functional communication gains were associated with similar frequency (⩾ 4 SLT-days/week) and greatest overall-language gains with higher frequency SLT (⩾ 6 days/weekly). Males' greatest gains were associated with SLT of moderate (functional communication; 3-to-4 h/weekly) or high intensity (overall-language and auditory comprehension; (> 9 h/weekly) compared to females for whom the greatest gains were associated with lower-intensity SLT (< 2 SLT-h/weekly). Consistencies across subgroups were also evident; greatest overall-language gains were associated with 20-to-50 SLT-h in total; auditory comprehension gains were generally observed when SLT > 9 h over ⩾ 4 days/week., Conclusions: We observed a treatment response in most subgroups' overall-language, auditory comprehension, and functional communication language gains. For some, the maximum treatment response varied in association with different SLT-frequency, intensity, and dosage. Where differences were observed, working-aged, chronic, mild-moderate, and male subgroups experienced their greatest language gains alongside high-frequency/intensity SLT. In contrast, older, moderate-severely impaired, and female subgroups within 3 months of aphasia onset made their greatest gains for lower-intensity SLT. The acceptability, clinical, and cost effectiveness of precision aphasia rehabilitation approaches based on age, sex, aphasia severity, and chronicity should be evaluated in future clinical RCTs.

Background: Speech and language therapy (SLT) benefits people with aphasia following stroke. Group level summary statistics from randomised controlled trials hinder exploration of highly complex SLT interventions and a clinically relevant heterogeneous population. Creating a database of individual participant data (IPD) for people with aphasia aims to allow exploration of individual and therapy-related predictors of recovery and prognosis., Aim: To explore the contribution that individual participant characteristics (including stroke and aphasia profiles) and SLT intervention components make to language recovery following stroke., Methods and Procedures: We will identify eligible IPD datasets (including randomised controlled trials, non-randomised comparison studies, observational studies and registries) and invite their contribution to the database. Where possible, we will use meta- and network meta-analysis to explore language performance after stroke and predictors of recovery as it relates to participants who had no SLT, historical SLT or SLT in the primary research study. We will also examine the components of effective SLT interventions., Outcomes and Results: Outcomes include changes in measures of functional communication, overall severity of language impairment, auditory comprehension, spoken language (including naming), reading and writing from baseline. Data captured on assessment tools will be collated and transformed to a standardised measure for each of the outcome domains., Conclusion: Our planned systematic-review-based IPD meta- and network meta-analysis is a large scale, international, multidisciplinary and methodologically complex endeavour. It will enable hypotheses to be generated and tested to optimise and inform development of interventions for people with aphasia after stroke., Systematic Review Registration: The protocol has been registered at the International Prospective Register of Systematic Reviews (PROSPERO; registration number: CRD42018110947).

Environmental reduplicative paramnesia (ERP) is characterized by the involuntary attribution of a false identity to a place. ERP has rarely been examined experimentally; its mechanisms therefore remain speculative. Here, we describe a patient with extended traumatic right fronto-temporal damage and severe persistent ERP, in whom we were able to modulate ERP by exposing him to various typical landmarks of the town where he was hospitalized. When landmarks were ambiguous as regards location (e.g., unknown buildings), the patient erroneously localized himself in his hometown, which was more than two thousand kilometers away. In contrast, when he visited distinct landmarks of the place where he actually resided, his ERP was immediately corrected, and spatial orientation was restored. These findings indicate that ERP may be temporarily modifiable through perception of unequivocal topographic information.

A woman produced spontaneous confabulations after rupture of an anterior communicating artery aneurysm. She confused currently irrelevant with currently relevant information in implicit memory; confabulations about people concerned only new acquaintances; false reality could be induced by an intensive 5-minute discussion; and in a recognition task, she confused false repetitions in another modality with real item repetitions. The findings support the theory that the defect causing spontaneous confabulation precedes conscious memory processing.