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A differential amplifier composed of an emitter-coupled pair is useful as an example in lecture presentations and laboratory experiments in electronic circuit analysis courses. However, in an active circuit with zero input load V[subscript id], both laboratory measurements and PSPICE and LTspice simulation results for the output voltage V[subscript o] are considerably lower than one base emitter unit V[subscript BE(on)] below the supply voltage V[subscript CC], as predicted by a textbook derivation. Modification of the derivation to include the p-n-p transistor base currents and the current gain beta[subscript P] and the supply voltage and specifications for the four transistors provide equations that predict results for V[subscript o] that are consistent with laboratory experience and computer simulations. The output voltage is in excess of three V[subscript BE(on)] units below V[subscript CC] when beta[subscript P] is 50. At larger values for beta[subscript P], V[subscript o] is increased by a factor proportional to 1/beta[subscript P], reaching one V[subscript BE(on)] unit below V[subscript CC] as beta[subscript P] approaches infinity. Larger values for V[subscript CC] cause an additional modest difference between V[subscript CC] and V[subscript o] at low values for beta[subscript P]. The derived equations and LTspice values are used to develop an empirical equation that predicts output voltages for the given Early voltages. The technique is adaptable to student data evaluation assignments. The computer simulations also showed that increased supply voltage results in increased gain for a given input value for V[subscript id], while larger values for beta[subscript P] result in a modest increase in gain at all values of V[subscript CC]. (Contains 5 tables and 6 figures.)

Objectives: Disrupted emotion processes are commonly linked to the onset and maintenance of auditory verbal hallucinations. However, a comprehensive approach using an extended emotion model has not previously been applied to voice-hearers to distinguish impairments in emotion processes from non-clinical populations. The present study hypothesised voice-hearers, as compared to controls, would have (1) higher reactivity to negative emotions and lower reactivity to positive emotions, (2) more difficulties regulating negative and positive emotions, (3) more maladaptive strategy use, and (4) higher alexithymia., Method: T-tests tested these hypotheses, comparing self-report measures of emotional reactivity, emotion regulation and alexithymia in voice-hearers (n = 50) to controls (n = 53)., Results: There were no group differences in emotional reactivity to positive or negative emotions. Compared to controls, voice-hearers showed difficulties in both positive and negative emotion regulation, were more likely to use expressive suppression, and were more likely to be alexithymic., Conclusions: These findings may help researchers and clinicians identify difficulties in voice-hearers' emotion processing, providing better direction for case formulation and treatment., (© 2024 The British Psychological Society.)

Many trauma-affected voice hearers report comorbid posttraumatic stress and voices (auditory verbal hallucinations) that are directly (voices repeat phrases spoken by perpetrators) or indirectly (voice content and trauma are thematically similar) related to their trauma. Models of PTSD and positive symptoms of psychosis are insufficient in explaining the comorbidity between PTSD and voices, and interventions based on these models have limited effectiveness in treating voices. This study presents a model that generates novel research into the factors underlying trauma-related voices that may inform effective interventions. Maintaining factors from existing models of PTSD and positive symptoms were combined into an integrative model of trauma-related voices. Theorised relationships between factors were used to identify possible differential pathways to direct and indirect voices. An integrative, trauma-related voices (TRV) model was developed that identifies multiple causal pathways to trauma-related voices. A future research agenda is proposed to test novel hypotheses based on the integrative model. The TRV model is a practical tool for complex case conceptualisation and generates novel hypotheses that may inform more effective treatments. Future studies are needed to test elements of the TRV model and should recruit transdiagnostic samples with diverse posttraumatic stress and voice hearing symptoms., (© 2024 John Wiley & Sons Ltd.)

Objective: People who hear voices (auditory verbal hallucinations) often have post-traumatic stress disorder (PTSD) symptoms. Cognitive behavioural therapies (CBT) have yielded inconsistent findings when treating voices and PTSD symptoms in voice hearers. Preliminary evidence suggests imagery rescripting (ImRs) is associated with large reductions in voice hearing and PTSD symptoms. This study replicated past studies using a larger sample to examine the effectiveness of ImRs in reducing such symptoms., Method: Participants (N = 49; 65.3% female; M age  = 35.86) were clients at an Australian transdiagnostic clinic for voice hearers. A one-arm open trial design was used with three pre-treatment baselines and a mid-treatment, post-treatment and 3-month follow up assessments of PTSD symptoms (Posttraumatic Diagnostic Scale for DSM-5), voices (Hamilton Program for Schizophrenia Voices Questionnaire) and emotional symptoms (Depression Anxiety and Stress Scales-21). Five single-item measures were administered weekly to explore the trajectories of change in trauma intrusions, voice-related distress, voice frequency and positive and negative voice valance., Results: ImRs was associated with very large reductions in PTSD symptoms and voices (both emotional and physical characteristics of voices) and emotional symptoms at post-treatment and follow-up (η 2 p  = 0.24-0.44). There were medium-large to large reductions in weekly symptoms of intrusions, voice-related distress, voice frequency and negative voices (η 2 p  = 0.12-0.16) and a non-significant increase in positive voices (η 2 p  = 0.05)., Conclusions: This study provides further evidence that ImRs is an effective treatment for voices and PTSD symptoms in voice hearers with a range of diagnoses. Randomised controlled trials are needed to compare the efficacy of ImRs to CBT protocols., (© 2024 The Author(s). Clinical Psychology & Psychotherapy published by John Wiley & Sons Ltd.)

Introduction: Visual hallucinations (VH) are more common than previously thought and are linked to higher levels of distress and disability in people with a psychotic illness. Despite this, scant attention has been given to VHs in the clinical literature, and the few therapy case series of cognitive behavioural therapy (CBT) published to date have not demonstrated reliable change. In other areas of clinical research, problematic mental imagery has been found to be more strongly related to negative affect in psychological disorders than negative linguistic thinking, and imagery focused techniques have commonly been found to improve the outcomes in CBT trials. Given VHs have many similarities with visual mental imagery and many of the distressing beliefs associated with VHs targeted in CBT are maintained by accompanying mental imagery (i.e., imaging a hallucinated figure attacking them), it seems plausible that an imagery-focused approach to treating VHs may be most effective., Methods: The current study is a multiple baseline case series (N = 11) of a 10-session imagery-focused therapy for VH in a transdiagnostic sample., Results: The study had good attendance and feedback, no adverse events and only one [seemly unrelated] drop-out, suggesting good feasibility, safety and acceptability. The majority of clients reported reduction on both full-scale measures (administered at 3 baselines, midtherapy, posttherapy and 3-month follow-up) and weekly measures of VH severity and distress, ranging from medium to large effect sizes., Conclusions: The case series suggests that an imagery-focused approach to treating VHs may be beneficial, with a recommendation for more rigorous clinical trials to follow., (© 2024 The Authors. Clinical Psychology & Psychotherapy published by John Wiley & Sons Ltd.)

The experience of hearing voices is common to an estimated 7% of the general population, with the presence of negative content being the best predictor of whether individuals will require clinical support. Whilst largely neglected in the literature to date, there are calls to consider the significance of voice content for reducing voice-related distress. However, no quantitative and comprehensive measure of voice content with suitability for research and clinical use exists. This pilot study aimed to demonstrate preliminary psychometric properties of a newly developed measure, the Perth Voice Content Questionnaire (PVCQ), designed to measure the intensity and themes of positively and negatively valenced voice content, primarily of the dominant voice. The PVCQ and measures of voice severity and related beliefs were completed by 47 voice-hearing participants. The measure was found to be internally consistent, loaded onto two distinct factors of positive and negative content, and these factors were associated with voice-related distress and negative beliefs about voices and positive beliefs about voices, respectively, indicating good validity. The PVCQ offers the first self-report measure of voice content, with preliminary psychometric properties indicating its suitability for clinical and research use., (© 2024 The Authors. Clinical Psychology & Psychotherapy published by John Wiley & Sons Ltd.)

Background: Research into hallucinatory experiences has focused primarily upon hallucinations within the auditory modality, to the relative neglect of other modalities. Furthermore, the exploration of auditory hallucinations (or 'voices') has focused primarily upon the experiences of people with a diagnosis of psychosis. The presence of multi-modal hallucinations may have implications across diagnoses for levels of distress, formulation and the targeting of psychological interventions., Methods: This study presents a cross-sectional analysis of observational data from the PREFER survey (N = 335). Linear regression was used to explore the relationships between voice-related distress and the presence, number, type and timing of multi-modal hallucinations., Results: Simple relationships were not found between distress and the presence of hallucinations in visual, tactile, olfactory or gustatory modalities, or in the number of modalities experienced. When considering the degree to which another modality hallucination was experienced simultaneously with voices, there was some evidence that the degree of co-occurrence with visual hallucinations was predictive of distress., Conclusions: The co-occurrence of voices with visual hallucinations may be associated with relatively greater distress, but not consistently, and the association between multimodal hallucinations and clinical impact appear complex and potentially variable from individual to individual. Further study of associated variables such as perceived voice power may further illuminate these relationships., Competing Interests: Declaration of competing interest The authors report no conflicts of interest., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Objectives: Post-traumatic stress is common among people who hear voices (auditory verbal hallucinations), many of whom hear trauma-related voices, whereby voice content is related to past trauma. Preliminary evidence suggests that imagery rescripting (ImRs) may more effectively reduce post-traumatic stress and voices compared to treatments that are based on existing models of PTSD or positive symptoms. No known studies have explored the potential maintaining factors of trauma-related voices in relation to ImRs. We aimed to uncover insights into the factors that maintain trauma-related voices and how ImRs may influence such factors by exploring voice hearers' explanations of voices and experiences of change throughout ImRs., Design: Thematic analytical methodology was used due to the study's critical epistemological framework., Methods: Semi-structured interviews explored relationships between trauma and voices, and experiences of change and stability throughout ImRs in a transdiagnostic sample (N = 10) who underwent 10-18 weekly ImRs sessions. Thematic analysis was used to develop themes., Results: Two themes captured explanations of voices, which suggested voices may have counterproductive protective functions. Three themes captured psychological experiences during ImRs, which reflected concepts such as freedom to experience emotions, and experiences of justice, closure and grieving. Three themes described the outcomes of ImRs, reflecting concepts such as increased confidence, coping, perceived safety and voices becoming less powerful., Conclusions: Trauma-related voices may have underlying protective functions and ImRs may support emotional expression, adaptive trauma re-appraisals and improve self-worth and coping self-efficacy. These change processes may have clinical implications in ImRs and other treatments for trauma-affected voice hearers., (© 2023 The Authors. Psychology and Psychotherapy: Theory, Research and Practice published by John Wiley & Sons Ltd on behalf of The British Psychological Society.)

Objectives: Extensive research has shown voice hearing to be associated with symptoms of Post-Traumatic Stress Disorder (PTSD) and dissociation. However, most studies have adopted a quantitative design, using cross-sectional data sampling methods, precluding temporal relationships between variables from being defined., Design: Using a qualitative design, this study sought to identify potential symptom relationships by addressing the research question: what is the nature of the temporal relationship between voices, dissociation and PTSD symptoms?, Methods: Seven voice hearers (aged 27 to 68 years) participated in a semi-structured interview exploring voice hearing, PTSD symptoms, and dissociation. The interviews were analysed using Interpretative Phenomenological Analysis., Results: One superordinate theme was identified in the data. Voices were observed to occur in dynamic interrelationship with PTSD symptoms and dissociation, and were frequently experienced before and after PTSD symptoms and dissociative episodes., Conclusions: Implications for theoretical understandings of voice hearing and future research are discussed., (© 2023 The Authors. Psychology and Psychotherapy: Theory, Research and Practice published by John Wiley & Sons Ltd on behalf of The British Psychological Society.)

Background: A range of traumas have been linked to voices (auditory verbal hallucinations) and unusual perceptual experiences (UPEs) in other perceptual-sensory domains. Models of PTSD and positive symptoms of psychosis are insufficient in explaining the relationship between trauma and voices. The trauma-related voices (TRV) model was developed to generate novel research in this area., Aims: This study aimed to investigate pathways from trauma to the frequency of UPEs based on a subset of hypothesised relationships in the TRV model., Materials: The PTSD Diagnostic Scale for DSM-5, State Adult Attachment Measure, Depression Anxiety and Stress Scales-21, Perth Emotion and Regulation Competency Inventory, Dissociative Experiences Measure Oxford, and Multi-modality Unusual Perceptual Experiences Questionnaire., Methods: We used path analysis in a non-clinical sample (N = 528) to model indirect effects from diverse trauma experiences to the frequency of multi-sensory UPEs via a subset of mediators within the TRV model: insecure attachment, emotion regulation deficits, negative affect and dissociation., Results: Our model was an excellent fit to the data and accounted for 37.1% of variance in UPE frequency, and all direct (βs = .14-.61) and indirect pathways (βs = .01-.08) were significant (ps < .001)., Discussion: Our findings suggest that insecure attachment may link diverse trauma experiences to emotion regulation deficits and negative affect, which are linked to UPE frequency via dissociation., Conclusion: Our findings provide preliminary evidence for a subset of relationships within the TRV model. Future studies are needed to gather stronger evidence of temporality and causation between these factors, and to test broader pathways within the TRV model., (© 2023 The Authors. Psychology and Psychotherapy: Theory, Research and Practice published by John Wiley & Sons Ltd on behalf of The British Psychological Society.)

It is unknown to what extent mental imagery and auditory verbal hallucinations (AVHs) are related. Trials evaluating this issue used both emotional and non-emotional mental imagery tools, thereby complicating outcomes comparisons. Therefore, the present study aimed to systematically review the literature on mental imagery in individuals with AVHs to (1) inventory imagery assessment tools used in this population, (2) to collect information on the relation between emotional and non-emotional mental imagery in all sensory domains and AVHs and (3) to integrate the outcomes of this systematic review in a model of different mental imagery domains and related assessment tools. We conducted a systematic literature search in the PubMed Database. After full-text screening, 17 papers were included. Findings showed that a variety of assessment methods have been used to assess various aspects of mental imagery in people with AVHs, suggesting that there is a lack of agreed theoretical conceptualization of mental imagery and AVHs. In addition, the studies confirmed as was expected that non-emotional mental imagery seemed unrelated to AVHs whereas emotional mental imagery was related to AVHs. Lastly, we proposed a model of mental imagery domains and corresponding assessment methods distinguishing between emotional and non-emotional mental imagery., (© 2023 The Authors. Clinical Psychology & Psychotherapy published by John Wiley & Sons Ltd.)

Background: Most voice hearers report childhood trauma. Many voice hearers report comorbid post-traumatic stress symptoms and that the content of their voices (auditory verbal hallucinations) is directly (voices repeat phrases spoken by perpetrators) or indirectly (voice content and trauma is thematically similar) related to their trauma. The factors that maintain trauma-related voices are unknown, and there is limited research in this area. This study aimed to identify potential maintaining factors of trauma-related voices by reviewing models of post-traumatic stress disorder (PTSD) and positive symptoms of psychosis., Method: Models of PTSD and positive symptoms were reviewed to identify potential factors that are unique and common to both sets of symptoms., Results: We reviewed 10 models of PTSD, 4 models of positive symptoms, and 2 trauma-informed models of voice hearing. One model provided a theoretical explanation of different types of trauma-related voices. Twenty-one factors were extracted from 16 theoretical models. No existing model incorporated all these factors., Discussion: Existing PTSD and positive symptom models present a range of common and unique factors. There may be value in extending existing integrative models to include a broader range of potential factors that could explain different pathways to, and expressions of, trauma-related voices. A future research agenda is presented to investigate how such an extension could lead to more complete individualized case formulations and targeted treatments., (© 2022 The Authors. Clinical Psychology & Psychotherapy published by John Wiley & Sons Ltd.)

Objective: People who experience distressing voices frequently report negative (e.g. abusive or threatening) voice content and this is a key driver of distress. There has also been recognition that positive (e.g. reassuring, or guiding) voice content contributes to better outcomes. Despite this, voice content has been neglected as a standalone outcome in evaluations of psychological therapies for distressing voices. We aimed to examine whether a modular cognitive-behavioural therapy (CBT) intervention for voices led to changes in negative and positive voice content., Design/methods: In a naturalistic, uncontrolled pre- and post- service evaluation study, 32 clients at an outpatient psychology service for distressing voices received eight sessions of CBT for distressing voices and completed self-report measures of negative and positive voice content at pre-, mid- and post- therapy., Results: There was no significant change in positive voice content. There was no significant change in negative voice content from pre- to post-therapy; however, there was a significant change in negative voice content between mid and post-treatment in which the cognitive therapy component was delivered. The CBT treatment was also associated with significant changes in routinely reported outcomes of voice-related distress and voice severity., Conclusions: The cognitive component of CBT for distressing voices may be associated with changes in negative, but not positive, voice content. There may be benefit to enhancing these effects by developing treatments targeting specific processes involved in negative and positive voice content and further exploring efficacy in well-powered, controlled trials with more comprehensive measures of voice content., (© 2022 The Authors. Psychology and Psychotherapy: Theory, Research and Practice published by John Wiley & Sons Ltd on behalf of The British Psychological Society.)

Traumatic life events are associated with increased risk of hearing voices and posttraumatic stress (PTS) symptoms have been implicated in this relationship. Studies indicate that increased self-compassion is associated with reduced PTS symptoms and voice-distress. The present study sought to examine whether self-compassion moderated the relationship between PTS symptoms and voice-distress. Self-report and clinician-administered questionnaires were used to measure self-compassion, PTS symptom severity, voice-frequency, and voice-distress in 62 trauma-affected voice-hearers who presented to a community voice-hearing clinic. Correlation analyses revealed that PTS symptom severity was positively correlated with voice-distress, but not voice-frequency, and that self-compassion was negatively correlated with voice-distress and PTS symptom severity. While self-compassion did not moderate the relationship between PTS symptom severity and voice-distress, it was associated with a significant reduction in voice-distress, at all levels of PTS symptom severity. Preliminary findings suggest self-compassion may play an important role in reducing voice-distress and thus warrant further consideration of self-compassion as a target in treatment for help-seeking voice-hearers., (© 2021 John Wiley & Sons, Ltd.)

Auditory verbal hallucinations, or voice hearing, is increasingly understood as a common experience. Despite this, voice hearers still experience a great deal of stigma, which can have serious negative impacts on the person's experience of their voices, and their recovery. Research has demonstrated that healthcare professionals may be a major source of the stigma surrounding voice hearing, with service-level implications for the development and delivery of evidence-based interventions. Therefore, reducing this stigma is a critical intervention target. The purpose of this narrative review is to examine evidence for interventions aimed at reducing stigma towards people who hear voices, in populations of healthcare professionals, students, and the general public. The available evidence supports the use of anti-stigma interventions based around direct contact with voice hearers and education about voice hearing. However, further research is necessary in this area to confirm these findings.

Despite being a relative common experience, hearing voices remains highly stigmatised, with serious consequences. Numerous interventions have been developed to reduce stigma towards mental illness in general, however most have failed to include implicit measures of stigma, and these have yet to be applied to hearing voices. The current study examined the efficacy of an education intervention in changing the explicit and implicit stigma held by healthcare professionals (N = 59) towards voice hearers. Results indicated that the education intervention led to significant decreases in explicit but not implicit measures of stigma, though participants demonstrated relatively positive baseline implicit attitudes towards voice hearers. These findings suggest that education interventions could be one way of reducing stigma towards voice hearers. Further research is necessary to explore the impact of education interventions in samples with more negative baseline attitudes, such as early career professionals, students, and the general population.