Striking loss of second language in bilingual patients with semantic dementia

Effects of Cerebellar Transcranial Direct Current Stimulation in Bilingual Logopenic Primary Progressive Aphasia

Background

Primary progressive aphasia (PPA) is a language-based dementia, causing progressive decline of language functions. Transcranial direct current stimulation (tDCS) can augment effects of speech-and language therapy (SLT). However, this has not been investigated in bilingual patients with PPA.

Objective

We evaluated the case of Mr. G., a French (native language, L1)/Dutch (second language, L2)-speaking 59-year-old male, with logopenic PPA, associated with Alzheimer's disease pathology. We aimed to characterize his patterns of language decline and evaluate the effects of tDCS applied to the right posterolateral cerebellum on his language abilities and executive control circuits.

Methods

In a within-subject controlled design, Mr. G received 9 sessions of sham and anodal tDCS combined with semantic and phonological SLT in L2. Changes were evaluated with an oral naming task in L2, the Boston Naming Task and subtests of the Bilingual Aphasia Test in in L2 and L1, the Stroop Test and Attention Network Test, before and after each phase of stimulation (sham/tDCS) and at 2-month follow-up.

Results

After anodal tDCS, but not after sham, results improved significantly on oral naming in L2, with generalization to untrained tasks and cross-language transfer (CLT) to L1: picture naming in both languages, syntactic comprehension and repetition in L2, and response times in the incongruent condition of the Attention Network Test, indicating increased inhibitory control.

Conclusions

Our preliminary results are the first to indicate that tDCS applied to the cerebellum may be a valuable tool to enhance the effects of SLT in bilingual patients with logopenic PPA.

Advances in semantic dementia: Neuropsychology, pathology & neuroimaging

Semantic dementia is a kind of neurodegenerative disorder, characterized by prominent semantic impairments and anterior temporal lobe atrophy. Since 2010, more studies have devoted to this rare disorder, revealing that it is more complex than we think. Clinical advances include more specific findings of semantic impairments and other higher order cognitive deficits. Neuroimaging techniques can help revealing the different brain networks affected (both structurally and functionally) in this condition. Pathological and genetic studies have also found more complex situations of semantic dementia, which might explain the huge variance existing in semantic dementia. Moreover, the current diagnosis criteria mainly focus on semantic dementia's classical prototype. We further delineated the features of three subtypes of semantic dementia based on atrophy lateralization with three severity stages. In a broader background, as a part of the continuum of neurodegenerative disorders, semantic dementia is commonly compared with other resembling conditions. Therefore, we summarized the differential diagnosis between semantic dementia and them. Finally, we introduced the challenges and achievements of its diagnosis, treatment, care and cross cultural comparison. By providing a comprehensive picture of semantic dementia on different aspects of advances, we hope to deepen the understanding of semantic dementia and promote more inspirations on both clinical and theoretical studies about it.

Universal and Language-Specific Connected Speech Characteristics of Bilingual Speakers With Alzheimer's Disease: Insights From Case Studies of Structurally Distinct Languages

PURPOSE

Connected speech analysis has been effectively utilized for the diagnosis and disease monitoring of individuals with Alzheimer's disease (AD). Existing research has been conducted mostly in monolingual English speakers with a noticeable lack of evidence from bilinguals and non-English speakers, particularly in non-European languages. Using a case study approach, we characterized connected speech profiles of two Bengali-English bilingual speakers with AD to determine the universal features of language impairments in both languages, identify language-specific differences between the languages, and explore language impairment characteristics of the participants with AD in relation to their bilingual language experience.

METHOD

Participants included two Bengali-English bilingual speakers with AD and a group of age-, gender-, education-, and language-matched neurologically healthy controls. Connected speech samples were collected in first language (L1; Bengali) and second language (L2; English) using a novel storytelling task (i.e., Frog, Where Are You?). These samples were analyzed using an augmented quantitative production analysis and correct information unit analyses for productivity, fluency, syntactic and morphosyntactic features, and lexical and semantic characteristics.

RESULTS

Irrespective of the language, AD impacted speech productivity (speech rate and fluency) and semantic characteristics in both languages. Unique language-specific differences were noted on syntactic measures (reduced sentence length in Bengali), lexical distribution (fewer pronouns and absence of reduplication in Bengali), and inflectional properties (no difficulties with noun or verb inflections in Bengali). Among the two participants with AD, the individual who showed lower proficiency and usage in L2 (English) demonstrated reduced syntactic complexity and morphosyntactic richness in English.

CONCLUSIONS

Evidence from these case studies suggests that language impairment features in AD are not universal across languages, particularly in comparison to impairments typically associated with language breakdowns in English. This study underscores the importance of establishing connected speech profiles in AD for non-English-speaking populations, especially for structurally different languages. This would in turn lead to the development of language-specific markers that can facilitate early detection of language deterioration and aid in improving diagnosis of AD in individuals belonging to underserved linguistically diverse populations.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.25412458.

Dual-Language Use and Cognitive Function Among Mexican Americans Aged 65 and Older

Background

Better English proficiency and higher frequency of using English among non-native speakers are associated with lower dementia risk.

Objective

We investigated if Mexican American older adults who use English and Spanish to a more similar degree demonstrate better cognitive function than those who use one language more than the other.

Methods

We used data from waves one (1992/93) to eight (2012/13) of the Hispanic Established Population for the Epidemiological Study of the Elderly. At baseline, participants were asked what language they usually use across communicative contexts. We based dual language on participants' use of Spanish and English within and across contexts. We categorized participants as low (n = 1,145), medium (n = 717), and high (n = 702) dual-language users. Linear mixed models were used to estimate the association between dual-language use, baseline Mini-Mental State Examination (MMSE) scores, and change in MMSE.

Results

Participants in the medium and high dual-language use categories scored 1.91 points and 3.03 points higher at wave one compared to the low dual-language use category. Adjusting for education reduced the association between dual-language use and baseline MMSE (medium B = 0.99 SE = 0.19 p < 0.01; high B = 1.41 SE = 0.21 p < 0.01). The association between dual-language use and decline in the MMSE was not statistically significant.

Conclusions

Greater dual-language use was associated with higher MMSE scores but not change in MMSE scores among Mexican Americans aged 65 and older. Future work should characterize bilingualism with greater nuance and use more rigorous cognitive measures to identify the components of the bilingual experience that may benefit the cognitive functioning of older adult bilinguals.

Jargonaphasia in logopenic variant primary progressive aphasia

BACKGROUND

Logopenic variant primary progressive aphasia (lvPPA), which is most commonly an early onset variant of Alzheimer's disease (AD), is a progressive impairment in word retrieval and language expression. Clinicians often misdiagnose these patients when they present with severely unintelligible speech consistent with jargonaphasia.

METHODS

We reviewed all patients presenting to a behavioral neurology program over a 23-year period who met criteria for lvPPA after completion of an evaluation extending to positron emission tomography (PET) of the brain. Among these lvPPA patients, we additionally identified and characterized those whose presentation involved incomprehensible yet fluent verbal output.

RESULTS

Out of 95 patients with lvPPA, 9 (9.47%) had jargonaphasia on presentation. These patients differed from the remaining 86 patients in lacking awareness or concern for their impaired communication, having worse mental status scale scores, greater auditory comprehension difficulty, and more bilateral temporo-parietal hypometabolism. In addition, 44.4% of those with jargonaphasia, compared to 14% of those without, were bi/multilingual.

CONCLUSION

Nearly 1 in 10 patients with lvPPA present with severely unintelligible speech. These patients have disease extending to bilateral temporoparietal areas affecting language comprehension and disease awareness. Jargonaphasia can be a confusing presentation of AD and must be differentiated from other progressive aphasias, Wernicke's aphasia, and the word salad of "schizoaphasia".

Nativity in the healthy migrant effect: Evidence from Australia

Migrant health constitutes an important public health issue; however, variations in the 'healthy migrant effect' among migrants of different nativity are not adequately understood. To fill this gap, this study examines the life expectancy (LE) and healthy life expectancy (HLE) of the Australian-born population and eight major migrant groups in Australia for 2006, 2011 and 2016. The results show that compared with the Australian-born population, the foreign-born population overall had a higher LE and HLE but a lower HLE/LE ratio. Considerable variations in migrant health status according to nativity were also observed. Specifically, migrants from South Africa, Britain and Germany exhibited a similar or higher LE, HLE and HLE/LE ratio, while those from China, India, Italy and Greece had a higher LE but a significantly lower HLE/LE ratio compared with the Australian-born population. Lebanese migrants were the only group who experienced an unchanging LE and a declining HLE from 2006 to 2016. These notable differences in migrants' health outcomes with respect to nativity may be explained by the sociocultural differences between the origin and host countries and the different extents of migration selectivity of different migrant groups. Targeted countermeasures such as improving the quality of life of migrants from culturally diverse backgrounds or with negative migration experiences are suggested.

Quality Improvement Framework to Examine Health Care Disparities in Behavioral Emergency Management in the Inpatient Medical Setting: A Consultation-Liaison Psychiatry Health Equity Project

BACKGROUND

De-escalation of behavioral emergencies in the inpatient medical setting may involve restrictive clinical interventions that directly challenge patient autonomy.

OBJECTIVE

We describe a quality improvement framework used to examine associations between patient characteristics and behavioral emergency de-escalation strategies. This project may inform other Consultation-Liaison Psychiatry teams seeking to promote equity in care.

METHODS

We examined behavioral emergency response team (BERT) management at an urban, tertiary-care medical center in the United States over a 3-year period. BERT data from an existing dataset were combined with demographic information from the hospital's electronic medical record. Race and ethnic identities were categorized as Black, Hispanic, Asian, White, and unknown. BERT events were coded based on the most restrictive intervention utilized per unique patient. Cross-tabulations and adjusted odds ratios from multivariate logistic regression were used to identify quality improvement targets in this exploratory project.

RESULTS

The sample included N = 902 patients and 1532 BERT events. The most frequent intervention reached was verbal de-escalation (n = 419 patients, 46.45%) and the least frequent was 4-point restraints (n = 29 patients, 3.2%). Half of BERT activations for Asian and a third for Hispanic patients required interpreter services. Anxiety and cognitive disorders and 2 BERT interventions, verbal de-escalation, and intramuscular/intravenous/ medications, were significantly associated with race/ethnic category. The most restrictive intervention for BERTs involving Black and Asian patients were verbal de-escalation (60.1%) and intramuscular/intravenous(53.7%), respectively. These proportions were higher compared with other race/ethnic groups. There was a greater percentage of patients from the unknown (6.3%) and Black (5.9%) race/ethnic groups placed in 4-point restraints compared with other groups (3.2%) that did not reach statistical significance. A logistic regression model predicting 4-point restraints indicated that younger age, multiple BERTs, and violent behavior as a reason for BERT activation, but not race/ethnic group, resulted in significantly higher odds.

CONCLUSIONS

This project illustrates that a quality improvement framework utilizing existing clinical data can be used to engage in organizational introspection and identify potential areas of bias in BERT management. Our findings suggest opportunities for further exploration, enhanced education, and programmatic improvements regarding BERT intervention; 4-point restraints; interpreter services; and the influence of race on perception of psychopathology.

Bilingual Primary Progressive Aphasia: A Scoping Review of Assessment and Treatment Practices

BACKGROUND

Primary progressive aphasia (PPA) is a neurodegenerative syndrome characterized by speech and/or language impairment with relatively spared cognition. Research investigating behavioral speech-language intervention and methods for cognitive-linguistic assessment in PPA has predominantly centered around monolingual speakers. This gap hinders the widespread adoption of evidence-based approaches and exacerbates the inequities faced by culturally and linguistically diverse populations living with PPA.

OBJECTIVE

This scoping review synthesizes the current evidence for assessment and treatment practices in bilingual PPA as well as the operationalization of bilingualism in PPA.

METHODS

Arksey & O'Malley's scoping review methodology was utilized. Information was extracted from each study and entered into a data-charting template designed to capture information regarding operationalization of bilingualism in PPA and assessment and treatment practices.

RESULTS

Of the 16 identified studies, 14 reported the results of assessments conducted in both languages. Three studies reported positive naming treatment outcomes. Thirteen studies included English-speaking participants, revealing linguistic bias. Most studies reported age of acquisition, proficiency, and patterns of language use rather than providing an operational definition for bilingualism.

CONCLUSIONS

Neither formal assessment measures nor clear guidelines for assessment of bilingual PPA currently exist; however, language-specific measures are emerging. Speech-language intervention in bilingual PPA has been relatively unexplored, representing a significant gap in the literature. In order to improve diagnostic and treatment options for bilingual PPA, targeted efforts to increase representation of bilinguals from various sociocultural contexts, as well as those who speak a variety of language pairs, is necessary.

Can Speaking More Than One Language Help Prevent Alzheimer's Disease?

Alzheimer's disease (AD) is an age-related neurocognitive disorder that is epidemic in the elderly population. Currently, there are limited pharmacological interventions, and this has heightened the urgency to identify potential preventable or modifiable risk factors that promote resilience to the neuropathological effects of AD. The regular use of two or more languages is one such factor that may increases cognitive reserve through the long-standing executive control involved in managing multiple languages in the brain. There is also evidence that bilingualism is associated with increased brain reserve or maintenance, particularly in frontal-executive structures and networks. This review examines the current, sometimes conflicting literature on bi/multilingualism and AD. These studies have confounding variations in the assessment of age of second language onset, language proficiency, language usage, and whether determining incidence of AD or age of symptom onset. Despite these limitations, most publications support the presence of increased frontal-executive reserve that compensates for the development of AD neuropathology and, thereby, delays the emergence of clinical symptoms of dementia by about 4-5 years. Although regularly speaking more than one language does not protect against AD neuropathology, the delay in its clinical expression has a potentially significant impact on the lifelong morbidity from this age-related disease. Learning other languages may be an important modifiable factor for delaying the clinical expression of AD in later life.

Can music enhance awareness in unresponsive people with severe dementia? An exploratory case series using behavioral, physiological and neurophysiological measures

In five people with severe dementia, we measured their behavioral and physiological responses to familiar/unfamiliar music and speech, and measured ERP responses to subject's own name (SON) after exposure to familiar/unfamiliar music or noise. We observed more frequent behavioral responses to personally-significant stimuli than non-personally-significant stumuli, and higher skin temperatures for music than non-music conditions. The control group showed typical ERPs to SON, regardless of auditory exposure. ERP measures were unavailable for the dementia group given challenges of measuring EEG in this population. The study highlights the potential for personally-significant auditory stimuli in enhancing responsiveness of people with severe dementia.

Frontotemporal Dementia: A Cross-Cultural Perspective

It is predictable that syndromes of frontotemporal dementia (FTD) may have a worldwide distribution; however, data available on their incidence and prevalence are variable. This variability most likely reflects disparities across regions in the distribution of the expertise, technology, and resources available for FTD research and care. Important discoveries have been made regarding FTD's phenotypes, genetics, and cultural influences on the expression of symptoms; however, in many countries, there are barriers posed by a dearth of resources. There are pressing needs to further develop research on FTD: including first, population studies designed to fill the gaps in our knowledge about FTD's frequency and risk factors in developing regions and among minority groups in developed countries. It is also necessary to facilitate the psychometric characterization of contemporary diagnostic criteria and their translation to different languages and cultural contexts. Furthermore, much needed is the analysis of differences in the genetic risk factors for FTD, particularly non-Mendelian susceptibility factors. It is hoped that reflections on FTD from an international perspective will spur an extension of the vibrant multicenter collaborations, that exist in North America and Europe, toward new centers to be established and supported in the developing regions of the world.

Lifelong Bilingualism Functions as an Alternative Intervention for Cognitive Reserve Against Alzheimer's Disease

Bilingualism has been reported to significantly delay the onset of dementia and plays an important role in the management of Alzheimer's disease (AD), a condition inducing impairment in the brain network and cognitive decline. Cognitive reserve is associated with the adaptive maintenance of neural functions by protecting against neuropathology. Bilingualism acts as a beneficial environmental factor contributing to cognitive reserve, although some potential confounding variables still need further elucidation. In this article, the relationship between bilingualism and cognitive reserve is discussed, interpreting the advantage of bilingualism in protecting against cognitive decline. In addition, the possible brain and biochemical mechanisms, supporting the advantageous effects of bilingualism in delaying the onset of dementia, involved in bilingualism are reviewed. Effectively, bilingualism can be considered as a pharmacological intervention with no side effects. However, the investigation of the pharmacological parameters of bilingualism is still at an early stage.

Language Breakdown in Primary Progressive Aphasias

Dementias with predominant language involvement, called primary progressive aphasias provide us with unique insight into systematic breakdown of language in neurodegenerative diseases and the structures and networks involved. Clinical and neuroimaging models quite distinct from those seen in stroke aphasias have evolved. In this short overview, we will discuss the cognitive processes involved in expressive and receptive verbal communication and how these processes are affected in the different variants of primary progressive aphasia producing distinctive clinical patterns. We will also discuss the brain's language network and how different components of the network break down in each of the primary progressive aphasia variants.

Multilingualism and semantic dementia - A case report

Language is a vital component of cognition essential for communication. Proficiency in more than one language has become a norm for many in the current era of globalisation. In neurogenerative conditions decline in language ability leads to early dependency. Studies have reported higher cognitive reserve in multilingual compared to monolinguals. Determining preserved language skills in a patient presenting with cognitive concerns helps in understanding the cognitive reserve, early signs of dementia, the extent of impairment due to language deficits and planning for cognitive stimulation. In this article, we have described an elderly woman with multilinguistic abilities who presented with semantic dementia.

Bilingualism Delays Expression of Alzheimer's Clinical Syndrome

OBJECTIVE

To evaluate the effects of bilingualism on the emergence of Alzheimer's clinical syndrome.

BACKGROUND

Studies have proposed an increase in cognitive and neural reserve from the management and control of two languages, with a consequent delayed expression of dementia.

METHODS

In a clinic with a large immigrant population, we identified 253 patients with probable Alzheimer's disease (AD) with intermediate or high evidence of AD pathophysiological process. These patients were reviewed for demographic variables, native language (L1) other than English, ages of onset and presentation, Mini-Mental State Examination (MMSE), digit spans, word fluencies, naming, and memory.

RESULTS

Among these patients, 74 (29.2%) were bilinguals with various L1s (Farsi, Spanish, Chinese, Tagalog, Arabic, others). When compared to the 179 monolingual AD patients, those who were bilingual had significant delays in ages of onset and presentation of approximately 4 years (p = 0.003). These delays persisted despite bilinguals having worse MMSE scores on presentation. There were no significant group differences on other variables except for worse naming in English among bilinguals versus monolinguals. Caregiver/informants reported that 66 (89.2%) of the 74 bilingual AD patients had gradually regressed to the predominant use of their L1.

CONCLUSIONS

In line with published reports worldwide, we found that bilingualism delays the expression of Alzheimer's clinical syndrome. We also found frequent reversion to the first learned language. These findings suggest that, among bilinguals, the availability of an L1 "back-up" either facilitates compensation or masks emergence of the early symptoms of dementia.