An online survey on clinical and healthy individuals with auditory verbal hallucinations: Abuse did not lead to more negative voice content.

Despite the clinical and theoretical importance of the negative content in auditory verbal hallucinations (AVHs), little research has been conducted on the topic. A handful of studies suggest that trauma or adverse life events contribute to negative content. The findings are somewhat inconsistent, however, possibly due to methodological limitations. Moreover, only trauma occurring in childhood has been investigated so far. In the present study, we studied the effect of abuse, experienced in either child- or adulthood, and clinical status on negative content of AVHs in four groups of participants that were assessed as part of a large, previously published online survey: Individuals with a psychotic disorder and AVHs (total n = 33), who had experienced abuse (n = 21) or not (n = 12) as well as a group of healthy individuals with AVHs (total n = 53), who had experienced abuse (n = 31) or not (n = 22). We hypothesized that having experienced abuse was associated with a higher degree of negative content. The clinical group collectively reported significantly higher degrees of negative AVHs content compared to the healthy group, but there was no effect of abuse on the degree of negative AVHs content. The presence of AVHs was more common amongst individuals who reported a history of abuse compared to individuals with no history of abuse, both in clinical and healthy participants with AVHs. This implies that at group level, being subjected to traumatic events increases an individual's vulnerability to experiencing AVHs. However, it does not necessarily account for negative content in AVHs.

Pilot-RCT Finds No Evidence for Modulation of Neuronal Networks of Auditory Hallucinations by Transcranial Direct Current Stimulation.

BACKGROUND: Transcranial direct current stimulation (tDCS) is used as treatment for auditory verbal hallucinations (AVH). The theory behind the treatment is that tDCS increases activity in prefrontal cognitive control areas, which are assumed to be hypoactive, and simultaneously decreases activity in temporal speech perception areas, which are assumed to be hyperactive during AVH. We tested this hypofrontal/hypertemporal reversal theory by investigating anatomical, neurotransmitter, brain activity, and network connectivity changes over the course of tDCS treatment. METHODS: A double-blind, randomized controlled trial was conducted with 21 patients receiving either sham or real tDCS treatment (2 mA) twice daily for 5 days. The anode was placed over the left dorsolateral prefrontal cortex (DLPFC) and the cathode over the left temporo-parietal cortex (TPC). Multimodal neuroimaging as well as clinical and neurocognitive functioning assessment were performed before, immediately after, and three months after treatment. RESULTS: We found a small reduction in AVH severity in the real tDCS group, but no corresponding neuroimaging changes in either DLPFCD or TPC. LIMITATIONS: The study has a small sample size. CONCLUSION: The results suggest that the currently leading theory behind tDCS treatment of AVH may need to be revised, if confirmed by studies with larger N. Tentative findings point to the involvement of Broca's area as a critical structure for tDCS treatment.

From core schemas about the self and others to voice phenomenology: Anxiety and depression affect voice hearers differently.

OBJECTIVES: Auditory verbal hallucinations (AVHs) occur as a symptom in various mental disorders, and show different phenomenological aspects, depending on their underlying psychopathology. Anxiety and depression, which are known to be involved in the development of AVHs, are suggested to amplify a vicious cycle in which negative interpretations of daily experiences feed into the formation of negative core schemas about the self and others. However, the way in which these variables interrelate is still unknown. Therefore, our aim was to determine the specific roles of anxiety and depression in the relationship between core schemas and emotional aspects of AVHs for three groups (non-clinical voice hearers, affective voice hearers and non-affective voice hearers). METHODS: Positive and negative core schemas of the self and others were tested as predictors of emotional distress due to AVHs, examining anxiety and depression separately as potential mediators. RESULTS: Results showed full mediating effects of depression in non-affective voice hearers in the relationship between negative core schemas and AVH distress, but not in affective voice hearers. Anxiety was not a mediator in any of the groups. CONCLUSIONS: These findings suggest different emotional mechanisms depending on the underlying psychopathology.

Transcranial direct current stimulation (tDCS) enhances internal source monitoring abilities in healthy participants.

Source monitoring refers to the ability to identify the origin of a memory, for example, whether you remember saying something or thinking about it, and confusions of these sources have been associated with the experience of auditory verbal hallucinations (AVHs). Both AVHs and source confusions are reported to originate from dysfunctional brain activations in the prefrontal cortex (PFC) and the superior temporal gyrus (STG); specifically, it is assumed that a hypoactive PFC and a hyperactive STG gives rise to AVHs and source confusions. We set out to test this assumption by trying to mimic this hypertemporal/hypofrontal model in healthy individuals with transcranial direct current stimulation (tDCS): the inhibitory cathode was placed over the left PFC and the excitatory anode over the left dorsolateral STG. Participants completed a reality monitoring task (distinguishing between external and internal memory sources) and an internal source monitoring task (distinguishing between two or more internal memory sources) in two separate experiments (offline vs. online tDCS). In the offline experiment (n = 34), both source monitoring tasks were completed after tDCS stimulation, and in the online experiment (n = 27) source monitoring tasks were completed while simultaneously being stimulated with tDCS. We found that internal source monitoring abilities were significantly enhanced during active online tDCS, while reality monitoring abilities were unaffected by stimulation in both experiments. We speculate, based on combining the present findings with previous studies, that there might be different brain areas involved in reality and internal source monitoring. While internal source monitoring seems to involve speech production areas, specifically Broca's area, as suggested in the present study, reality monitoring seems to rely more on the STG and DLPFC, as shown in other studies of the field.

Mapping psychotic-like experiences: Results from an online survey.

Suggestions have been made that psychotic-like experiences (PLEs), such as hallucinatory and delusional experiences, exist on a continuum from healthy individuals to patients with a diagnosis of schizophrenia. We used the screening questions of the Questionnaire for Psychotic Experiences (QPE), an interview that captures the presence and phenomenology of various psychotic experiences separately, to assess PLEs in Norway. Based on data from an online survey in a sample of more than 1,400 participants, we demonstrated that the QPE screening questions show satisfactory psychometric properties. Participants with mental disorders reported more frequent lifetime and current hallucinatory experiences than participants without mental disorders. Childhood experiences were rather low and ranged from 0.7% to 5.2%. We further replicated findings that young age, illegal drug use, lower level of education, and having parents with a mental disorder are associated with higher endorsement rates of PLEs. Finally, a binomial regression revealed that the mere presence of PLEs does not discriminate between individuals with and without a mental disorder. Taken together, the findings of the present study support existing models that both hallucinations and delusions exist on a structural and phenomenological continuum. Moreover, we demonstrated that the QPE screening questions can be used by themselves as a complementary tool to the full QPE interview.

A multimodal study of the effects of tDCS on dorsolateral prefrontal and temporo-parietal areas during dichotic listening.

The underlying neural mechanisms of transcranial direct current stimulation (tDCS), especially beyond the primary motor cortex, remain unclear. Several studies examined tDCS effects on either functional activity, neurotransmitters or behavior but few investigated those aspects together to reveal how the brain responds to tDCS. The objective is to elucidate the underlying mechanisms of tDCS using a multimodal approach that extends from behavioral to neurotransmitter levels of explanation. Thirty-two healthy participants performed an auditory dichotic listening task at two visits, one session with sham and one session with real tDCS (2 mA) while simultaneously undergoing functional magnetic resonance imaging (fMRI). The anode and cathode were placed over the left temporo-parietal cortex (TPC) and dorsolateral prefrontal cortex, respectively. Before and after simultaneous dichotic listening/fMRI/tDCS, combined glutamate and glutamine (Glx) and myo-inositol levels were assessed in the stimulated areas. While fMRI and dichotic listening showed expected functional activity and behavioral effects, neither method demonstrated differences between real and sham stimulation. Glx only showed a statistical trend towards higher levels after real tDCS in both stimulated brain areas. There were no significant correlations between behavior and Glx. Despite a reasonable sample size, electrical field strength, and replication of behavioral and functional activity results, tDCS had little to no effect on dichotic listening, Glx, and functional activity. The study emphasizes that findings about the underlying neural mechanisms of the primary motor cortex cannot simply be generalized to other brain areas. Particularly, the TPC might be less sensitive to tDCS. Moreover, the study demonstrates the general feasibility of multimodal approaches.

Personal resilience factors protect against distressing auditory hallucinations: A study comparing psychotic patients with auditory hallucinations, non-patients with auditory hallucinations, and healthy controls.

Although studies have identified several risk factors for the development of psychotic disorders, potential protective factors - such as resilience - have rarely been examined. Studies suggest that the negative beliefs people hold about their Auditory Hallucinations (AH) may be an indicator of a need for care. However, the reason why certain people do not develop negative beliefs is unclear but may be related to resilience. The present study aimed to examine the role of resilience in AH by comparing psychotic patients with AH, non-patients with AH, and healthy controls without AH. Another aim was to explore whether resilience is related to the beliefs people hold about their AH. Results revealed that patients with AH and non-patients with AH had similarly weak interpersonal resilience factors compared to healthy controls without AH. In contrast, patients with AH showed weak personal factors of resilience compared to both non-patients with AH and healthy controls without AH. Patients with AH had more negative and fewer positive beliefs about their AH than non-patients with AH. Finally, the personal factors of resilience were related to the beliefs about AH. These results showed that personal factors of resilience are decisive variables influencing the need for care in people experiencing AH and thus represent an important treatment target.

No effect of electrical transcranial direct current stimulation adjunct treatment for epilepsia partialis continua in POLG disease.

We report a 15-year-old female with POLG-related mitochondrial disease who developed severe multifocal epilepsia partialis continua, unresponsive to standard anti seizure drug treatment and general anesthesia. Based on an earlier case report, we treated her focal seizures that affected her right upper limb with 20-min sessions of transcranial direct current stimulation (tDCS) at an intensity of 2 mA on each of five consecutive days. The cathode was placed over the left primary motor cortex, the anode over the contralateral orbitofrontal cortex. Surface electromyography (EMG) were recorded 20 min before, 20 min during, and 20 min after four of five tDCS sessions to measure its effect on the muscle jerks. The electroencephalography (EEG) was recorded before and after tDCS to measure the frequency of spikes. Our results showed no statistically or clinically significant reduction of seizures or epileptiform activity using EEG and EMG, with this treatment protocol. To our knowledge, this is only the second time that adjunct tDCS treatment of epileptic seizures has been tried in POLG-related mitochondrial disease. Taken together with the positive findings from the earlier case report, the present study highlights that more data are needed to determine if, and under which parameters, the treatment is effective.