Subjective language aptitude linked to distinct neural patterns in Broca’s area BA44

In mental disorders the language dimension, including speech and thought, is often impaired. In psychosis, the dimension of language symptoms represents a great variability between the patients. To study language as continuum from health to psychosis a dimensional approach is needed. Consequently, we examined the heterogeneity of a healthy population during a language task in functional magnetic resonance imaging (fMRI), in relation to a subjective rating of one’s language aptitude. The aim was to study the spectrum of inter-individual differences and its connectivity from Broca’s area with language-related brain areas. The observed heterogeneity in the healthy group would enable an extrapolation to observable clinical side of the continuum. In this study, 102 healthy adult participants were asked to rate on a 7-ponit Likert scale, how they perceived their own language aptitude. Allowing us to separate participants, according to their rating, into groups of high, mid or low language aptitude. Furthermore, they completed a lexical priming task, while measuring brain activity in functional magnetic resonance imaging (fMRI). Participants had to decide, if a visually presented target word would reflect the generic term of a previously presented a prime word, in terms of its category (e.g. Apple – Fruit) or its relation (e.g. Apple – Pear). Although reaction time (RT) and accuracy showed no significant differences between all three groups, the psychophysiological interaction (PPI) analysis of BA44 and reaction time revealed distinct connectivity patterns from BA44 among the high and low language aptitude groups in the preparation phase (waiting for the target after the indication of task type). We found that a stronger connectivity from BA44 to the left posterior middle temporal gyrus (MTG) was associated with faster RT in the high group. The low group showed a similar pattern, but from BA44 to the left fusiform gyrus, also known as the visual word form area. These results show that, according to subjective evaluation of their own language aptitude, different neural connectivity routes are activated. These insights into the dimension of language is helping future research, that analyzes the continuum from the healthy population profiles to the profiles of the population with psychosis

«Subjective language aptitude is linked to neural activity in Broca’s area, but not to objective performance during a semantic priming task»

Language, including speech and thought, is often affected in mental illnesses. In psychosis, the dimension of language symptoms shows a great variability between patients. A dimensional approach allows to study language as continuum from health to psychosis. Therefore, in the current study, we investigated the heterogeneity of a healthy population during a language task, additionally to a subjective rating of one’s language aptitude. The aim was to analyze the spectrum of inter-individual differences and its association with language-related brain networks, specifically Broca’s area. The observed heterogeneity in the healthy group would enable an extrapolation to clinical end of the spectrum. To this end, 102 healthy adult subjects performed a lexical priming task while measuring brain activity with fMRI. Subjects had to indicate whether a visually presented target word would form the generic term of a previously shown a prime word, in terms of its category (e.g. Apple – Fruit) or its relation (e.g. Apple – Pear). To see the difference in language aptitude, we asked the participants to rate on 7-point Likert scale, how they thought their language abilities are. According to the rating they were then grouped into high, mid or low language aptitude groups. Although reaction time (RT) and accuracy showed no significant differences between all three groups, we found differences in brain activation in BA45 among the language aptitude groups. We looked at activation in the Broca areas (BA45, BA44) during preparation (waiting for the target after the indication of task type) and processing (target word processing) phases. We found differences between the groups in BA45 during the preparation and processing phases. The Post hoc analysis revealed that the high group showed significantly greater activation in BA45 compared to the low group, while there was no significant difference between the groups in BA 44. Furthermore, the RT was correlated with activation of BA 45 in the high language aptitude group during the preparation phase, indicating that increased activation in BA45 reflects faster responses in the high language aptitude group. Moreover, for the other two groups correlations with RT were found in BA44. These results show that, according to subjective evaluation of their own language aptitude, one differently utilizes the language-related brain areas during the language task. These insights into the dimension of language is facilitating upcoming research, that compares these healthy population profiles to the profiles of a population with psychosis

Neural Correlates of Semantic Priming in Psychosis

Psychoses are aetiologically complex disorders that affect about 1 − 2% of the population during their lifetime. Psychotic symptoms are thought to represent disturbances in higher-order brain functions that can be grouped according to their dysfunction in one or more of the following three neural brain circuitries: language, affect, motor function. Dysfunction of the neural language brain circuitry has already been linked to disturbances in expressive speech and formal thought disorders. However, it remains currently unknown if the language brain circuitry is only disturbed in psychosis, or if already individuals at familial or clinical high-risk show some extend of aberrancy. To examine the whole spectrum form health to psychosis, four different subject groups are being examined: healthy controls (HC), first-degree relatives of psychosis patients (REL), a clinical high-risk group (CHR) and psychosis patients (PAT). In total, 120 subjects (30 per group) will complete a lexical priming task during electroencephalography and functional magnetic resonance imaging. On a behavioural level, we expect to find subtle language dysfunction in the REL and CHR group. Furthermore, we hypothesize that aberrant neural activation patterns are present during the language task in PAT, CHR and REL groups in comparison to HC individuals. Finally, we aim to depict that aberrant neural activation in language - related brain areas is most pronounced in the PAT group and to a lesser extend present in the REL group. With this study, we hope to improve diagnostic strategies, treatments and outcome predictions

Emotional dysregulation in psychosis – proof of concept in healthy controls

Objectives: Psychosis symptoms occur in around 1-2% of the population during their lifetime. Various psychosis symptoms relate to a disturbed perception and regulation of emotions. Previous research indicates that emotional dysregulation may form a distinct psychosis symptom dimension that is linked to aberrant function and structure of the limbic system and its cortico-basal ganglia and cortico-cortical connections. However, the nature of emotional dysregulation in psychosis has not been studied extensively yet. Therefore, we aim to investigate affect as a dimension and its association with neural activation in limbic brain structures in psychosis patients as well as in healthy subjects. As a first step, we analysed preliminary data to investigate our self-developed task. Methods Neural activation patterns were investigated using functional magnetic resonance imaging (fMRI) from 12 healthy controls. During fMRI examination, we used a specifically developed face perception task. The presented stimuli were short animations of faces that varied in certain characteristics: gender (male, female), aesthetic (high, low), head movement (up, down) and gaze direction (direct, averted). Subsequently, all face stimuli were rated with regard to gender, health, trustworthiness, friendliness, attractiveness & dominance. Results/Conclusion: During the perception of the face animation, there was predominantly increased activity in face processing areas (i.e. fusiform gyrus) and decreased activity in other face processing areas (i.e. lingual gyrus, superior temporal gyrus) and limbic areas (i.e. posterior cingulate). More data and further investigations are required to investigate the affect domain in detail. Furthermore, comparison with psychosis patients might help find the underlying psychopathology of psychosis and therefore improve future prevention, diagnostic and treatment options

Jumping to Associations during Psychosis

Objectives: Psychoses are aetiologically complex disorders that affect about 1 − 2% of the population during their lifetime. Psychotic symptoms are thought to represent disturbances in higher-order brain functions that can be grouped according to their dysfunction in one or more of the following three neural brain circuitries: language, affect, motor function. Dysfunction of the neural language brain circuitry has already been linked to disturbances in expressive speech and formal thought disorders. However, it remains currently unknown if all psychosis patients show to some extent a disruption in the language brain circuitry or if this is only the case for patients with language and thought disturbances. Furthermore, it is still unclear if the language brain circuitry is only disturbed in psychosis, or if already individuals at familial or clinical high-risk show some extend of aberrancy. Methods: To examine the whole spectrum form health to psychosis, four different subject groups are being examined: healthy controls, first-degree relatives of psychosis patients, a clinical high-risk group and psychosis patients. In total, 120 subjects (30 per group) will complete a lexical priming task during electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). The lexical priming task consists of two subtasks. During the category subtask, subjects have to decide whether a visually presented target word forms the generic term of the previously shown prime word in terms of its category (e.g. Apple – Fruit). During the association subtask, participants have to indicate whether a visually presented target word is related to the content of a previously shown prime word (e.g. Apple – Pear). Expected Results: Preliminary data from the fMRI part will be shown from this proof of concept study. In this sample, both conditions revealed a bilateral activation pattern in the IFG (Broca’s region). Thus, the language task activates the neural language circuitry

Neural Correlates of Semantic Priming in Psychosis

Psychoses are aetiologically complex disorders that affect about 1 − 2% of the population during their lifetime. Psychotic symptoms are thought to represent disturbances in higher-order brain functions that can be grouped according to their dysfunction in one or more of the following three neural brain circuitries: language, affect, motor function. Dysfunction of the neural language brain circuitry has already been linked to disturbances in expressive speech and formal thought disorders. However, it remains currently unknown if the language brain circuitry is only disturbed in psychosis, or if already individuals at familial or clinical high-risk show some extend of aberrancy. To examine the whole spectrum form health to psychosis, four different subject groups are being examined: healthy controls (HC), first-degree relatives of psychosis patients (REL), a clinical high-risk group (CHR) and psychosis patients (PAT). In total, 120 subjects (30 per group) will complete a lexical priming task during electroencephalography and functional magnetic resonance imaging. On a behavioural level, we expect to find subtle language dysfunction in the REL and CHR group. Furthermore, we hypothesize that aberrant neural activation patterns are present during the language task in PAT, CHR and REL groups in comparison to HC individuals. Finally, we aim to depict that aberrant neural activation in language - related brain areas is most pronounced in the PAT group and to a lesser extend present in the REL group. With this study, we hope to improve diagnostic strategies, treatments and outcome predictions