Linguistic findings in persons with schizophrenia-a review of the current literature.

Introduction: Alterations of verbalized thought occur frequently in psychotic disorders. We characterize linguistic findings in individuals with schizophrenia based on the current literature, including findings relevant for differential and early diagnosis. Methods: Review of literature published via PubMed search between January 2010 and May 2022. Results: A total of 143 articles were included. In persons with schizophrenia, language-related alterations can occur at all linguistic levels. Differentiating from findings in persons with affective disorders, typical symptoms in those with schizophrenia mainly include so-called "poverty of speech," reduced word and sentence production, impaired processing of complex syntax, pragmatic language deficits as well as reduced semantic verbal fluency. At the at-risk state, "poverty of content," pragmatic difficulties and reduced verbal fluency could be of predictive value. Discussion: The current results support multilevel alterations of the language system in persons with schizophrenia. Creative expressions of psychotic experiences are frequently found but are not in the focus of this review. Clinical examinations of linguistic alterations can support differential diagnostics and early detection. Computational methods (Natural Language Processing) may improve the precision of corresponding diagnostics. The relations between language-related and other symptoms can improve diagnostics.

GHB: a life-threatening drug complications and outcome of GHB detoxification treatment-an observational clinical study.

BACKGROUND: GHB (gammahydroxybutyrate) and its precursors are popular recreational drugs due to their sedative, anxiolytic and sexually stimulating effects. Their use has been steadily increasing in recent years. The detoxification process is complex and prone to high rates of complications while little is known about the pathophysiology. This study aims to elucidate the characteristics of GHB-addicted patients and to evaluate the risks and complications of GHB withdrawal treatment. METHODS: This observational study describes prospectively the socioeconomic status, clinical history and course of inpatient detoxification treatment of a group of 39 patients suffering from GHB substance use disorder. Detoxification treatment took place in a highly specialized psychiatric inpatient unit for substance use disorders. RESULTS: GHB patients were characterised by being young, well-educated and by living alone. More than 50% of the patients had no regular income. The patients were male and female in equal numbers. Detoxification treatment was complicated, with high rates of delirium (30.8%) and high need for intensive care (20.5%). CONCLUSIONS: In our sample, GHB users were young, well-educated people and male and female in equal number. Detoxification proved to be dangerous for GHB-addicted patients. The presence of delirium and the need for transfer to an intensive care unit during detoxification treatment was extraordinarily high, even with appropriate clinical treatment. The reasons for this remain unknown. Therefore an intensive care unit should be available for GHB detoxification treatment. Further studies are needed to evaluate the options for prophylactic treatment of delirium during detoxification.

Tracing embodied word production in persons with Parkinson's disease in distinct motor conditions.

Embodied cognition theories posit direct interactions between sensorimotor and mental processing. Various clinical observations have been interpreted in this controversial framework, amongst others, low verb generation in word production tasks performed by persons with Parkinson's disease (PD). If this were the consequence of reduced motor simulation of prevalent action semantics in this word class, reduced PD pathophysiology should result in increased verb production and a general shift of lexical contents towards particular movement-related meanings. 17 persons with PD and bilateral deep brain stimulation (DBS) of the subhtalamic nucleus (STN) and 17 healthy control persons engaged in a semantically unconstrained, phonemic verbal fluency task, the former in both DBS-off and DBS-on states. The analysis referred to the number of words produced, verb use, and the occurrence of different dimensions of movement-related semantics in the lexical output. Persons with PD produced fewer words than controls. In the DBS-off, but not in the DBS-on condition, the proportion of verbs within this reduced output was lower than in controls. Lowered verb production went in parallel with a semantic shift: in persons with PD in the DBS-off, but not the DBS-on condition, the relatedness of produced words to own body-movement was lower than in controls. In persons with PD, DBS induced-changes of the motor condition appear to go along with formal and semantic shifts in word production. The results are compatible with the idea of some impact of motor system states on lexical processing.

Motor signature of autism spectrum disorder in adults without intellectual impairment.

Motor signs such as dyspraxia and abnormal gait are characteristic features of autism spectrum disorder (ASD). However, motor behavior in adults with ASD has scarcely been quantitatively characterized. In this pilot study, we aim to quantitatively examine motor signature of adults with ASD without intellectual impairment using marker-less visual-perceptive motion capture. 82 individuals (37 ASD and 45 healthy controls, HC) with an IQ > 85 and aged 18 to 65 years performed nine movement tasks and were filmed by a 3D-infrared camera. Anatomical models were quantified via custom-made software and resulting kinematic parameters were compared between individuals with ASD and HCs. Furthermore, the association between specific motor behaviour and severity of autistic symptoms (Autism Diagnostic Observation Schedule 2, Autism Spectrum Quotient) was explored. Adults with ASD showed a greater mediolateral deviation while walking, greater sway during normal, tandem and single leg stance, a reduced walking speed and cadence, a greater arrhythmicity during jumping jack tasks and an impaired manual dexterity during finger tapping tasks (p < 0.05 and |D|> 0.48) compared to HC. Furthermore, in the ASD group, some of these parameters correlated moderately to severity of ASD symptoms. Adults with ASD seem to display a specific motor signature in this disorder affecting movement timing and aspects of balance. The data appear to reinforce knowledge about motor signs reported in children and adolescents with ASD. Also, quantitative motor assessment via visual-perceptive computing may be a feasible instrument to detect subtle motor signs in ASD and perhaps suitable in the diagnosis of ASD in the future.

Dopamine-Related Reduction of Semantic Spreading Activation in Patients With Parkinson's Disease.

Impaired performance in verbal fluency (VF) tasks is a frequent observation in Parkinson's disease (PD). As to the nature of the underlying cognitive deficit, it is commonly attributed to a frontal-type dysexecutive syndrome due to nigrostriatal dopamine depletion. Whereas dopaminergic medication typically improves VF performance in PD, e.g., by ameliorating impaired lexical switching, its effect on semantic network activation is unclear. Data from priming studies suggest that dopamine causes a faster decay of semantic activation spread. The aim of the current study was to examine the impact of dopaminergic medication on the dynamic change of word frequency during VF performance as a measure of semantic spreading activation. To this end, we performed a median split analysis of word frequency during phonemic and semantic VF task performance in a PD group tested while receiving dopaminergic medication (ON) as well as after drug withdrawal (i.e., OFF), and in a sample of age-matched healthy volunteers (both groups n = 26). Dopaminergic medication in the PD group significantly affected phonemic VF with improved word production as well as increased error-rates. The expected decrease of word frequency during VF task performance was significantly smaller in the PD group ON medication than in healthy volunteers across semantic and phonemic VF. No significant group-difference emerged between controls and the PD group in the OFF condition. The comparison between both treatment conditions within the PD group did not reach statistical significance. The observed pattern of results indicates a faster decay of semantic network activation during lexical access in PD patients on dopaminergic medication. In view of improved word generation, this finding is consistent with a concept of more focused neural activity by an increased signal-to-noise ratio due to dopaminergic neuromodulation. However, the effect of dopaminergic stimulation on VF output suggests a trade-off between these beneficial effects and increased error-rates.

Effects of thalamic and basal ganglia deep brain stimulation on language-related functions - Conceptual and clinical considerations.

Deep Brain Stimulation (DBS) is a therapy for various neurological movement disorders. It acts predominantly on motor symptoms, but may unfold a number of mostly subtle cognitive effects. In this regard, reports on particular language-related DBS sequels are comparably frequent, but difficult to overlook, given the heterogeneity of targeted structures in the brain, treated diseases, assessment methods and results reported. Accordingly, available knowledge was organized with respect to important aspects, such as the main DBS loci and surgical versus neuromodulatory therapy actions. Current views of biolinguistic underpinnings of the reviewed data, their clinical relevance and potential implications are discussed.

Thalamic but Not Subthalamic Neuromodulation Simplifies Word Use in Spontaneous Language.

Several investigations have shown language impairments following electrode implantation surgery for Deep Brain Stimulation (DBS) in movement disorders. The impact of the actual stimulation, however, differs between DBS targets with further deterioration in formal language tests induced by thalamic DBS in contrast to subtle improvement observed in subthalamic DBS. Here, we studied speech samples from interviews with participants treated with DBS of the thalamic ventral intermediate nucleus (VIM) for essential tremor (ET), or the subthalamic nucleus (STN) for Parkinson's disease (PD), and healthy volunteers (each n = 13). We analyzed word frequency and the use of open and closed class words. Active DBS increased word frequency in case of VIM, but not STN stimulation. Further, relative to controls, both DBS groups produced fewer open class words. Whereas VIM DBS further decreased the proportion of open class words, it was increased by STN DBS. Thus, VIM DBS favors the use of relatively common words in spontaneous language, compatible with the idea of lexical simplification under thalamic stimulation. The absence or even partial reversal of these effects in patients receiving STN DBS is of interest with respect to biolinguistic concepts suggesting dichotomous thalamic vs. basal ganglia roles in language processing.

Impact of deep brain stimulation of the subthalamic nucleus on natural language in patients with Parkinson's disease.

BACKGROUND: In addition to the typical motor symptoms, a majority of patients suffering from Parkinson's disease experience language impairments. Deep Brain Stimulation of the subthalamic nucleus robustly reduces motor dysfunction, but its impact on language skills remains ambiguous. METHOD: To elucidate the impact of subthalamic deep brain stimulation on natural language production, we systematically analyzed language samples from fourteen individuals (three female / eleven male, average age 66.43 ± 7.53 years) with Parkinson's disease in the active (ON) versus inactive (OFF) stimulation condition. Significant ON-OFF differences were considered as stimulation effects. To localize their neuroanatomical origin within the subthalamic nucleus, they were correlated with the volume of tissue activated by therapeutic stimulation. RESULTS: Word and clause production speed increased significantly under active stimulation. These enhancements correlated with the volume of tissue activated within the associative part of the subthalamic nucleus, but not with that within the dorsolateral motor part, which again correlated with motor improvement. Language error rates were lower in the ON vs. OFF condition, but did not correlate with electrode localization. No significant changes in further semantic or syntactic language features were detected in the current study. CONCLUSION: The findings point towards a facilitation of executive language functions occurring rather independently from motor improvement. Given the presumed origin of this stimulation effect within the associative part of the subthalamic nucleus, this could be due to co-stimulation of the prefrontal-subthalamic circuit.

Age-related dissociation of N400 effect and lexical priming.

The use of contextual information is an important capability to facilitate language comprehension. This can be shown by studying behavioral and neurophysiological measures of accelerated word recognition when semantically or phonemically related information is provided in advance, resulting in accompanying attenuation of the respective event-related potential, i.e. the N400 effect. Against the background of age-dependent changes in a broad variety of lexical capacities, we aimed to study whether word priming is accomplished differently in elderly compared to young persons. 19 young (29.9 ± 5.6 years) and 15 older (69.0 ± 7.2 years) healthy adults participated in a primed lexical decision task that required the classification of target stimuli (words or pseudo-words) following related or unrelated prime words. We assessed reaction time, task accuracy and N400 responses. Acceleration of word recognition by semantic and phonemic priming was significant in both groups, but resulted in overall larger priming effects in the older participants. Compared with young adults, the older participants were slower and less accurate in responding to unrelated word-pairs. The expected N400 effect was smaller in older than young adults, particularly during phonemic word and pseudo-word priming, with a rather similar N400 amplitude reduction by semantic relatedness. The observed pattern of results is consistent with preserved or even enhanced lexical context sensitivity in older compared to young adults. This, however, appears to involve compensatory cognitive strategies with higher lexical processing costs during phonological processing in particular, suggested by a reduced N400 effect in the elderly.

A Vector Space Model for Neural Network Functions: Inspirations From Similarities Between the Theory of Connectivity and the Logarithmic Time Course of Word Production.

The present report examines the coinciding results of two study groups each presenting a power-of-two function to describe network structures underlying perceptual processes in one case and word production during verbal fluency tasks in the other. The former is theorized as neural cliques organized according to the function N = 2 i - 1, whereas the latter assumes word conglomerations thinkable as tuples following the function N = 2 i . Both theories assume the innate optimization of energy efficiency to cause the specific connectivity structure. The vast resemblance between both formulae motivated the development of a common formulation. This was obtained by using a vector space model, in which the configuration of neural cliques or connected words is represented by a N-dimensional state vector. A further analysis of the model showed that the entire time course of word production could be derived using basically one single minimal transformation-matrix. This again seems in line with the principle of maximum energy efficiency.

Increased conceptual switching by dopaminergic treatment in patients with Parkinson's disease.

Cognitive changes including reduced word production in verbal fluency (VF) tasks are frequently observed in Parkinson's disease (PD) with ambiguous effects of dopaminergic medication on these symptoms. Here, we studied the impact of dopaminergic medication on specific cognitive components underlying VF task performance in 21 participants with PD on their regular medication and following dopamine withdrawal compared with healthy controls. We used temporal cluster analysis (TCA) to differentiate phases of VF output relating to fast automatic lexical activation ('clusters') and slower attention-demanding shifts ('switches'). Dopaminergic medication led to increased switching and, in non-alternating VF tasks, to the formation of smaller and shorter word clusters. The number of switches was correlated with higher cognitive scores and showed an inverse relationship with VF error rates. Increased switching operations during VF task performance can be interpreted in view of nigrostriatal dopaminergic roles for balancing system state versus change propensities. The additional effect on word clustering suggests a modulation of semantic spreading activation mechanisms underlying lexical search, presumably involving non-nigrostriatal, e.g., mesocortical dopaminergic networks.

Mindfulness-Based Interventions for In-Patients With Schizophrenia Spectrum Disorders-A Qualitative Approach.

In recent years, mindfulness-based interventions (MBI) have gained clinical relevance in the treatment of patients with schizophrenia spectrum disorders (SSDs). High symptom burden, long durations of hospitalization and high rehospitalization rates demonstrate the severity and cost-intensity of these disorders. MBIs have shown promising treatment outcomes in a small number of trials, primarily taking place in English-speaking countries. The current study aims to explore mechanisms and processes as well as adverse effects of MBIs on in-patients with SSDs in a German university hospital setting. A qualitative design based on inductive thematic analysis accompanied by quantitative assessments was chosen. A semi-structured interview guide was developed by psychiatrists and psychologists to assess patient experiences, perceptions, thoughts, and feelings during and after taking part in a MBI. Twenty-seven interviews were conducted between September 2017 and October 2018 with in-patients who are diagnosed with schizophrenia or schizoaffective disorder. Rater-based questionnaires, such as the Positive and Negative Syndrome Scale (PANSS), Montgomery Asberg Depression Rating Scale (MADRS), and Psychotic Symptom Rating Scales-Auditory Hallucination (PSYRATS-AH) were administered at baseline to collect clinical outcomes. Qualitative analysis revealed two domains: content and function. In the first domain related to content with the core elements "detachment and rumination", "presence and getting lost", "non-judgment and judgment", and effects with "emotions", "cognition", and "symptom changes". A second domain related to function was extracted, including the relevance of perception of context and transfer to everyday life. Overall, improvements concerning cognition, distress, and psychopathology were detected, while no adverse effects, such as increased psychotic symptoms, were revealed. As the first study of its kind, mechanisms, processes, and the safety of MBIs were explored and confirmed in a sample of German in-patients with SSDs. The results of this qualitative study are in line with recent findings on MBIs amongst patients with psychotic disorders from other countries. Results lay the ground for future research to focus on the systematic study of MBIs in large samples, its treatment processes, outcomes, and effectiveness for in-patients with SSDs.

Small Semantic Networks in Individuals with Autism Spectrum Disorder Without Intellectual Impairment: A Verbal Fluency Approach.

Individuals with Autism Spectrum Disorder (ASD) experience a variety of symptoms sometimes including atypicalities in language use. The study explored differences in semantic network organisation of adults with ASD without intellectual impairment. We assessed clusters and switches in verbal fluency tasks ('animals', 'human feature', 'verbs', 'r-words') via curve fitting in combination with corpus-driven analysis of semantic relatedness and evaluated socio-emotional and motor action related content. Compared to participants without ASD (n = 39), participants with ASD (n = 32) tended to produce smaller clusters, longer switches, and fewer words in semantic conditions (no p values survived Bonferroni-correction), whereas relatedness and content were similar. In ASD, semantic networks underlying cluster formation appeared comparably small without affecting strength of associations or content.

Relationships between activity and well-being in people with parkinson's disease.

Objectives: The complex symptomatology of Parkinson' disease (PD) usually goes along with reduced physical activity. Previous studies have indicated positive effects of activating therapies on patients' well-being. This study, therefore, examined how activity in daily life is related to patients' subjective condition. Materials and Methods: Twenty-one PD patients rated their condition every two hours during two routine days and documented the duration and type of their activities (based on the PRISCUS-Physical Activity Questionnaire) during the respective time intervals. They were furthermore assessed regarding motor and nonmotor symptoms, personality factors, and coping strategies. Results: Patients spent on average 8.59 ± 2.93 hr per day at physical rest and 5.47 ± 2.93 hr physically active. We found highly significant associations between positive condition ratings (such as happiness, motivation, and concentration) and the duration of subsequent physical activities (adj.r2  = .689) as well as between the duration of these activities and a subsequent improvement in the subjective condition (adj.r2  = .545). This was strongest in patients using active coping strategies and showing agreeable and conscientious personality traits (adj.r2  = .380). Nonmotor symptom severity was weakly inversely related to the daily amount of activities (adj.r2  = .273), whereas no significant association with motor symptom severity was found. Conclusions: The results suggest a feedback process between a positive subjective condition and physical activities in PD patients. This appears to depend on the use of active coping strategies and nonmotor symptoms rather than on motor symptom severity. The results should encourage physicians to address the importance of everyday physical activities and to provide patients with behavioral advice.

Theory of mind performance in Parkinson's disease is associated with motor and cognitive functions, but not with symptom lateralization.

Next to the typical motor signs, Parkinson's disease (PD) goes along with neuropsychiatric symptoms, amongst others affecting social cognition. Particularly, Theory of Mind (ToM) impairments have mostly been associated with right hemispherical brain dysfunction, so that it might prevail in patients with left dominant PD. Fourty-four PD patients, twenty-four with left and twenty with right dominant motor symptoms, engaged in the Reading the Mind in the Eyes (RME) and the Faux Pas Detection Test (FPD) to assess affective and cognitive ToM. The results were correlated with performance in further cognitive tests, and analyzed with respect to associations with the side of motor symptom dominance and severity of motor symptoms. No association of ToM performance with right hemispheric dysfunction was found. RME results were inversely correlated with motor symptom severity, while FPD performance was found to correlate with the performance in verbal fluency tasks and the overall cognitive evaluation. Affective ToM was found associated with motor symptom severity and cognitive ToM predominantly with executive function, but no effect of PD lateralization on this was identified. The results suggest that deficits in social cognition occur as a sequel of the general corticobasal pathology in PD, rather than as a result of hemisphere-specific dysfunction.

Subcortical roles in lexical task processing: Inferences from thalamic and subthalamic event-related potentials.

Subcortical functions for language capacities are poorly defined, but may be investigated in the context of deep brain stimulation. Here, we studied event-related potentials recorded from electrodes in the subthalamic nucleus (STN) and the thalamic ventral intermediate nucleus (VIM) together with surface-EEG. Participants completed a lexical decision task (LDT), which required the differentiation of acoustically presented words from pseudo-words by button press. Target stimuli were preceded by prime-words. In recordings from VIM, a slow potential shift apparent at the lower electrode contacts persisted during target stimulus presentation (equally for words and pseudo-words). In contrast, recordings from STN electrodes showed a short local activation on prime-words but not target-stimuli. In both depth-recording regions, further components related to contralateral motor responses to target words were evident. On scalp level, mid-central activations on (pseudo)lexical stimuli were obtained, in line with the expression of N400 potentials. The prolonged activity recorded from VIM, exclusively accompanying the relevant LDT phase, is in line with the idea of thalamic "selective engagement" for supporting the realization of the behavioral focus demanded by the task. In contrast, the phasic prime related activity rather indicates "procedural" STN functions, for example, for trial sequencing or readiness inhibition of prepared target reactions. Hum Brain Mapp 38:370-383, 2017. © 2016 Wiley Periodicals, Inc.

Thalamic deep brain stimulation decelerates automatic lexical activation.

BACKGROUND: Deep Brain Stimulation (DBS) of the thalamic ventral intermediate nucleus (VIM) is a therapeutic option for patients with essential tremor. Despite a generally low risk of side effects, declines in verbal fluency (VF) have previously been reported. OBJECTIVES: We aimed to specify effects of VIM-DBS on major cognitive operations needed for VF task performance, represented by clusters and switches. Clusters are word production spurts, thought to arise from automatic activation of associated information pertaining to a given lexical field. Switches are slow word-to-word transitions, presumed to indicate controlled operations for stepping from one lexical field to another. PATIENTS & METHODS: Thirteen essential tremor patients with VIM-DBS performed verbal fluency tasks in their VIM-DBS ON and OFF conditions. Clusters and switches were formally defined by mathematical criteria. All results were compared to those of fifteen healthy control subjects, and significant OFF-ON-change scores were correlated to stimulation parameters. RESULTS: Patients produced fewer words than healthy controls. DBS ON compared to DBS OFF aggravated this deficit by prolonging the intervals between words within clusters, whereas switches remained unaffected. This stimulation effect correlated with more anterior electrode positions. CONCLUSION: VIM-DBS seems to influence word output dynamics during verbal fluency tasks on the level of word clustering. This suggests a perturbation of automatic lexical co-activation by thalamic stimulation, particularly if delivered relatively anteriorly. The findings are discussed in the context of the hypothesized role of the thalamus in lexical processing.

Deep Brain Stimulation of the Subthalamic Nucleus Improves Lexical Switching in Parkinsons Disease Patients.

OBJECTIVE: Reduced verbal fluency (VF) has been reported in patients with Parkinson's disease (PD), especially those treated by Deep Brain Stimulation of the subthalamic nucleus (STN DBS). To delineate the nature of this dysfunction we aimed at identifying the particular VF-related operations modified by STN DBS. METHOD: Eleven PD patients performed VF tasks in their STN DBS ON and OFF condition. To differentiate VF-components modulated by the stimulation, a temporal cluster analysis was performed, separating production spurts (i.e., 'clusters' as correlates of automatic activation spread within lexical fields) from slower cluster transitions (i.e., 'switches' reflecting set-shifting towards new lexical fields). The results were compared to those of eleven healthy control subjects. RESULTS: PD patients produced significantly more switches accompanied by shorter switch times in the STN DBS ON compared to the STN DBS OFF condition. The number of clusters and time intervals between words within clusters were not affected by the treatment state. Although switch behavior in patients with DBS ON improved, their task performance was still lower compared to that of healthy controls. DISCUSSION: Beyond impacting on motor symptoms, STN DBS seems to influence the dynamics of cognitive procedures. Specifically, the results are in line with basal ganglia roles for cognitive switching, in the particular case of VF, from prevailing lexical concepts to new ones.

Effects of thalamic deep brain stimulation on spontaneous language production.

The thalamus is thought to contribute to language-related processing, but specifications of this notion remain vague. An assessment of potential effects of thalamic deep brain stimulation (DBS) on spontaneous language may help to delineate respective functions. For this purpose, we analyzed spontaneous language samples from thirteen (six female / seven male) patients with essential tremor treated with DBS of the thalamic ventral intermediate nucleus (VIM) in their respective ON vs. OFF conditions. Samples were obtained from semi-structured interviews and examined on multidimensional linguistic levels. In the VIM-DBS ON condition, participants used a significantly higher proportion of paratactic as opposed to hypotactic sentence structures. This increase correlated negatively with the change in the more global cognitive score, which in itself did not change significantly. In conclusion, VIM-DBS appears to induce the use of a simplified syntactic structure. The findings are discussed in relation to concepts of thalamic roles in language-related cognitive behavior.