Improving the measurement and acoustic performance of transparent face masks and shields.

Opaque face masks harm communication by preventing speech-reading (lip-reading) and attenuating high-frequency sound. Although transparent masks and shields (visors) with clear plastic inserts allow speech-reading, they usually create more sound attenuation than opaque masks. Consequently, an iterative process was undertaken to create a better design, and the instructions to make it are published. The experiments showed that lowering the mass of the plastic inserts decreases the high-frequency sound attenuation. A shield with a clear thermoplastic polyurethane (TPU) panel had an insertion loss of (2.0 ± 1.1) dB for 1.25-8 kHz, which improves on previous designs that had attenuations of 11.9 dB and above. A cloth mask with a TPU insert was designed and had an insertion loss of (4.6 ± 2.3) dB for 2-8 kHz, which is better than the 9-22 dB reported previously in the literature. The speech intelligibility index was also evaluated. Investigations to improve measurement protocols that use either mannikins or human talkers were undertaken. Manufacturing variability and inconsistency of human speaking were greater sources of experimental error than fitting differences. It was shown that measurements from a mannikin could match those from humans if insertion losses from four human talkers were averaged.

Neuropsychological and psychiatric outcomes in encephalitis: A multi-centre case-control study.

OBJECTIVES: Our aim was to compare neuropsychological and psychiatric outcomes across three encephalitis aetiological groups: Herpes simplex virus (HSV), other infections or autoimmune causes (Other), and encephalitis of unknown cause (Unknown). METHODS: Patients recruited from NHS hospitals underwent neuropsychological and psychiatric assessment in the short-term (4 months post-discharge), medium-term (9-12 months after the first assessment), and long-term (>1-year). Healthy control subjects were recruited from the general population and completed the same assessments. RESULTS: Patients with HSV were most severely impaired on anterograde and retrograde memory tasks. In the short-term, they also showed executive, IQ, and naming deficits, which resolved in the long-term. Patients with Other or Unknown causes of encephalitis showed moderate memory impairments, but no significant impairment on executive tests. Memory impairment was associated with hippocampal/medial temporal damage on magnetic resonance imaging (MRI), and naming impairment with left temporal and left frontal abnormalities. Patients reported more subjective cognitive complaints than healthy controls, with tiredness a significant problem, and there were high rates of depression and anxiety in the HSV and the Other encephalitis groups. These subjective, self-reported complaints, depression, and anxiety persisted even after objectively measured neuropsychological performance had improved. CONCLUSIONS: Neuropsychological and psychiatric outcomes after encephalitis vary according to aetiology. Memory and naming are severely affected in HSV, and less so in other forms. Neuropsychological functioning improves over time, particularly in those with more severe short-term impairments, but subjective cognitive complaints, depression, and anxiety persist, and should be addressed in rehabilitation programmes.

Delineating the cognitive-neural substrates of writing: a large scale behavioral and voxel based morphometry study.

The current study investigated the cognitive and neural substrates that underpin writing ability. We explored similarities and differences in writing numbers and words and compared these to language and manual actions in a large group of sub-acute, stroke patients (n = 740). The behavioral data showed association and dissociation in the ability to write words and numbers. Comorbidities of writing deficits with both language and motor impairments were prevalent, with less than a handful showing deficits restricted to the writing tasks. A second analysis with a subset of patients (n = 267) explored the neural networks that mediate writing abilities. Lesion to right temporal contributed to writing words, while lesions to left postcentral contributed to writing numbers. Overlapping neural mechanisms included the bilateral prefrontal cortex, right inferior parietal, left middle occipital and the right cerebellum. With the former regions associated with error pattern typical to writing based on prior knowledge (the lexical route), while lesion to left MOG was associated with errors to the phonological (non-lexical) route. Using principle components extracted from the behavioral data, we showed that right prefrontal and right parietal contributed to the ability to use pen, while lesion to bilateral prefrontal, inferior temporal and cerebellum supported unique use of pen for writing. The behavioral and imaging data suggested that writing numbers and words primarily relied on overlapping cognitive and neural functions. Incidents of pure writing deficits, in the absence of motor or language deficits were rare. Nevertheless, the PCA and neural data suggested that writing abilities were associated with some unique neuro-cognitive functions, specifically dedicated to the use of pen and the ability to transform meaning to motor command.

mHealth and memory aids: levels of smartphone ownership in patients.

BACKGROUND: The use of mobile devices to deliver healthcare has not yet been exploited in neuropsychological rehabilitation. Smartphones have the potential to serve as multi-functional memory aids. AIMS: To investigate whether patients attending a clinic for mixed memory problems own smartphones, to determine whether this could be a widely applicable medium to use as a memory aids device. METHODS: A questionnaire on smartphone ownership was given to an opportunity sample of consecutive patients attending a neuropsychiatry and memory disorders outpatient clinic. Data were collected in 2012 and repeated 12 months later in 2013 to assess changes over time. RESULTS: Ownership of mobile phones was stable between 2012 (81%) and 2013 (85%), but ownership of smartphones showed a significant increase (from 26% to 40%). Age negatively predicted smartphone ownership. CONCLUSION: Despite cognitive or psychiatric problems, our patient group are as likely to own a mobile phone as a member of the general population. Ownership levels are at 40% and likely to increase in the future. Exploring how smartphones and their apps could function as memory aids is likely to be useful for a large enough number of patients to be clinically worthwhile.

The BCoS cognitive profile screen: Utility and predictive value for stroke.

OBJECTIVE: We examined the utility of the Birmingham Cognitive Screen (BCoS) in discriminating cognitive profiles and recovery of function across stroke survivors. BCoS was designed for stroke-specific problems across 5 cognitive domains: (a) controlled and spatial attention, (b) language, (c) memory, (d) number processing, and (e) praxis. METHOD: On the basis of specific inclusion criteria, this cross-section observational study analyzed cognitive profiles of 657 subacute stroke patients, 331 of them reassessed at 9 months. Impairments on 32 measures were evaluated by comparison with 100 matched healthy controls. Measures of affect, apathy, and activities of daily living were also taken. Between-subjects group comparisons of mean performance scores and impairment rates and within-subject examination of impairment rates over time were conducted. Logistic regressions and general linear modeling were used for multivariate analysis of domain-level effects on outcomes. RESULTS: Individuals with repeated stroke experienced significantly less cognitive recovery at 9 months than those with a first stroke despite similar initial level of cognitive performance. Individuals with left hemisphere lesions performed more poorly than those with right hemisphere lesions, but both groups showed similar extent of recovery at 9 months. BCoS also revealed lesion-side-specific deficits and common areas of persistent problems. Functional outcome at 9 months correlated with domain-level deficits in controlled attention, spatial attention, and praxis over and above initial dependency and concurrent levels of affect and apathy. CONCLUSION: The study demonstrates how BCoS can identify differential cognitive profiles across patient groups. This can potentially help predict outcomes and inform rehabilitation.

Temporal grouping modulates ipsilateral capture in right visual neglect.

The current study assessed the performance of a patient with right neglect (M.A.H.) across various manipulations of the flanker paradigm. When required to identify a central target in the presence of a unilateral flanker, M.A.H. responded to the flanking distractor on the left (ipsilesional) side as if it were the target, even when the flanker appeared at left peripheral locations. A right (contralesional) flanker did not affect central identification performance (Experiment 1). The "ipsilesional capture" effect persisted when pretrial location markers were introduced to make the flanker and target locations more clearly defined (Experiment 2). However, when the ipsilesional flanker appeared simultaneously with a contralesional flanker, central target detection improved to ceiling (Experiment 3). Interestingly, with these three-stimulus displays, congruency effects in reaction time only occurred in relation to the flanker on the contralesional side (Experiment 3), suggesting impaired response selectivity to ipsilesional stimuli. Congruency effects were produced on both sides only when the two flanking distractors grouped together (by both onset and offset, Experiment 4) and when the ipsilesional flanking distractor grouped with the target by onset (lone contra offset, Experiment 4). The results are attributed to ipsilesional capture in central target detection, which is offset by temporal grouping processes when another stimulus appears on the contralateral side.

The link between STM and sentence comprehension: a neuropsychological rehabilitation study.

A memory rehabilitation study was conducted with two patients with contrasting impairments in verbal short-term memory (STM): one with impaired phonological STM (pSTM) and one with impaired semantic STM (sSTM). Two treatments were employed, each designed to improve separate aspects of STM: phonological and semantic. The pSTM treatment selectively improved sensitivity to phonological effects in STM, and the sSTM treatment brought about increased lexical effects on verbal STM performance. There was also some evidence of type-specific generalisation to sentence comprehension, in that the pSTM patient showed post-treatment improvement on sentence repetition after the pSTM treatment, and the sSTM patient showed improved sentence anomaly judgement after the sSTM but not the pSTM treatment. The findings are discussed in relation to theories on the components involved in STM, and the role of STM in sentence processing.

Type-specific proactive interference in patients with semantic and phonological STM deficits.

Prior neuropsychological evidence suggests that semantic and phonological components of short-term memory (STM) are functionally and neurologically distinct. The current paper examines proactive interference (PI) from semantic and phonological information in two STM-impaired patients, DS (semantic STM deficit) and AK (phonological STM deficit). In Experiment 1 probe recognition tasks with open and closed sets of stimuli were used. Phonological PI was assessed using nonword items, and semantic and phonological PI was assessed using words. In Experiment 2 phonological and semantic PI was elicited by an item recognition probe test with stimuli that bore phonological and semantic relations to the probes. The data suggested heightened phonological PI for the semantic STM patient, and exaggerated effects of semantic PI in the phonological STM case. The findings are consistent with an account of extremely rapid decay of activated type-specific representations in cases of severely impaired phonological and semantic STM.

Overcoming the effect of letter confusability in letter-by-letter reading: a rehabilitation study.

Patients who read in a letter-by-letter manner can demonstrate effects of lexical variables when reading words comprised of low confusability letters, suggesting the capacity to process low-confusability words in parallel across the letters (Fiset, Arguin, & McCabe, 2006). Here a series of experiments is presented investigating letter confusability effects in MAH, a patient with expressive and receptive aphasia who shows reduced reading accuracy with longer words, and DM, a relatively "pure" alexic patient. Two rehabilitation studies were employed: (i) a word-level therapy and (ii) a letter-level therapy designed to improve discrimination of individual letters. The word-level treatment produced generalised improvement to low-confusability words only, but the serial processing treatment produced improvement on both high and low confusability words. The results add support to the hypothesis that letter confusability plays a key role in letter-by-letter reading, and suggest that a rehabilitation method aimed at reducing ambiguities in letter identification may be particularly effective for treating letter-by-letter reading.

Rehabilitation of spelling in a participant with a graphemic buffer impairment: the role of orthographic neighbourhood in remediating the serial position effect.

Graphemic Output Buffer (GOB) disorder is defined as difficulty with the serial output of a sequence of letters in the output stage of the spelling process. In their rehabilitation study with a GOB patient, Sage and Ellis ( 2006 ) found that improvement on treated words generalised to untreated words from the same orthographic neighbourhoods as treated items, but not to other unrelated words. GOB patients frequently show a bow-shaped accuracy curve across letter positions, where letters at the middle positions are most error-prone. It may be that consistent letters at these middle letter positions across neighbourhoods modulate this effect. Spelling was treated using an Anagram and Copy Treatment (ACT) and generalisation to three untreated sets was examined: (1) neighbours of treated words with shared middle letters (e.g., clock-block), (2) neighbours with different medial position letters (e.g., clock-click), and (3) unrelated words (e.g., clock-puppy). Improvement was found for untreated neighbours with shared middle letters. There was no effect of training on the unrelated word set, and a negative impact on untreated neighbours with changed middle letters after the treatment. We attribute these results to top-down support from learned lexical representations, which facilitate spelling of untreated neighbours with shared middle letters but impede neighbours with changed middle letters. This latter result is attributed to interference from neighbours in the trained set strengthening competing letter representations at middle positions.