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BACKGROUND: Experiences of felt presence (FP) are well documented in neurology, neuropsychology and bereavement research, but systematic research in relation to psychopathology is limited. FP is a feature of sensorimotor disruption in psychosis, hypnagogic experiences, solo pursuits and spiritual encounters, but research comparing these phenomena remains rare. A comparative approach to the phenomenology of FP has the potential to identify shared and unique processes underlying the experience across these contexts, with implications for clinical understanding and intervention. METHODS: We present a mixed-methods analysis from three online surveys comparing FP across three diverse contexts: a population sample which included people with experience of psychosis and voice-hearing (study 1, N = 75), people with spiritual and spiritualist beliefs (study 2, N = 47) and practitioners of endurance/solo pursuits (study 3, N = 84). Participants were asked to provide descriptions of their FP experiences and completed questionnaires on FP frequency, hallucinatory experiences, dissociation, paranoia, social inner speech and sleep. Data and code for the study are available via OSF. RESULTS: Hierarchical linear regression analysis indicated that FP frequency was predicted by a general tendency to experience hallucinations in all three studies, although paranoia and gender (female > male) were also significant predictors in sample 1. Qualitative analysis highlighted shared and diverging phenomenology of FP experiences across the three studies, including a role for immersive states in FP. CONCLUSIONS: These data combine to provide the first picture of the potential shared mechanisms underlying different accounts of FP, supporting a unitary model of the experience.
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Transtornos Psicóticos , Humanos , Masculino , Feminino , Transtornos Psicóticos/psicologia , Alucinações/psicologia , Inquéritos e Questionários , Emoções , Transtornos ParanoidesRESUMO
Introduction: In several sub-fields of psychology, there has been a renewed focus on measurement practices. As far as we are aware, this has been absent in hallucinations research. Thus, we investigated (a) cross-study variation in how hallucinatory experiences are measured and (b) the reliability of measurements obtained using two tasks that are widely employed in hallucinations research.Method: In Study 1, we investigated to what extent there was variation in how the Launay-Slade Hallucination Scale (LSHS) has been used across 100 studies. In Study 2, we investigated the reliability of the measurements obtained through source monitoring and signal detection tasks, using data from four recent publications. Materials/data are available at doi: 10.17605/osf.io/d3gnk/.Results: In Study 1, we found substantial variation in how hallucinatory experiences were assessed using the LSHS and that descriptions of the LSHS were often incomplete in important ways. In Study 2, we reported a range of reliability estimates for the measurements obtained using source monitoring and signal discrimination tasks. Some measurements obtained using source monitoring tasks had unacceptably low levels of reliability.Conclusions: Our findings suggest that suboptimal measurement practices are common in hallucinations research and we suggest steps researchers could take to improve measurement practices.
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Alucinações , Alucinações/psicologia , Humanos , Reprodutibilidade dos TestesRESUMO
Hallucinatory experiences can occur in both clinical and nonclinical groups. However, in previous studies of the general population, investigations of the cognitive mechanisms underlying hallucinatory experiences have yielded inconsistent results. We ran a large-scale preregistered multisite study, in which general-population participants (N = 1,394 across 11 data-collection sites and online) completed assessments of hallucinatory experiences, a measure of adverse childhood experiences, and four tasks: source memory, dichotic listening, backward digit span, and auditory signal detection. We found that hallucinatory experiences were associated with a higher false-alarm rate on the signal detection task and a greater number of reported adverse childhood experiences but not with any of the other cognitive measures employed. These findings are an important step in improving reproducibility in hallucinations research and suggest that the replicability of some findings regarding cognition in clinical samples needs to be investigated.
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Cognição , Alucinações , Percepção Auditiva , Humanos , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Cognitive behavioural therapy for psychosis (CBTp) is a recommended treatment for psychotic experiences, but its effectiveness has been questioned. One way of addressing this may be to tailor therapy materials to the phenomenology of specific psychotic experiences. AIM: In this study, we investigated the acceptability of a novel treatment manual for subtypes of 'voice-hearing' experiences (i.e. auditory verbal hallucinations). An uncontrolled, single-arm design was used to assess feasibility and acceptability of using the manual in routine care for people with frequent voice-hearing experiences. METHOD: The manual was delivered on a smart tablet and incorporated recent research evidence and theory into its psychoeducation materials. In total, 24 participants completed a baseline assessment; 19 started treatment, 15 completed treatment and 12 participants completed a follow-up assessment (after 10 sessions of using the manual). RESULTS: Satisfaction with therapy scores and acceptability ratings were high, while completion rates suggested that the manual may be more appropriate for help with participants from Early Intervention in Psychosis services rather than Community Mental Health Teams. CONCLUSION: Within-group changes in symptom scores suggested that overall symptom severity of hallucinations - but not other psychosis features, or beliefs about voices - are likely to be the most appropriate primary outcome for further evaluation in a full randomised controlled trial.
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Terapia Cognitivo-Comportamental , Transtornos Psicóticos , Estudos de Viabilidade , Alucinações/terapia , Audição , Humanos , Transtornos Psicóticos/terapiaRESUMO
Introduction: It has been proposed that hallucinations occur because of problems with reality discrimination (when internal, self-generated cognitions are misattributed to an external, non-self source) and because of elevated levels of top-down processing. In this study, we examined whether visual reality discrimination abilities and elevated top-down processing (assessed via face pareidolia-proneness) were associated with how often non-clinical participants report visual hallucination-like experiences.Methods: Participants (N = 82, mean age = 23.12 years) completed a visual reality discrimination task and a face pareidolia task, as well as self-report measures of schizotypy and of the frequency of visual hallucination-like experiences.Results: Regression analysis demonstrated that the number of false alarms made on the visual reality discrimination task and the number of hits made on the face pareidolia task were independent predictors of the frequency of visual hallucination-like experiences. Correlations between performance on the tasks and levels of schizotypy were not statistically significant.Conclusions: These findings suggest that weaker visual reality discrimination abilities and elevated levels of top-down processing are associated with visual hallucination-proneness and are discussed in terms of the idea that clinical visual hallucinations and non-clinical visual hallucination-like experiences share similar cognitive mechanisms.
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Discriminação Psicológica/fisiologia , Alucinações/diagnóstico , Alucinações/psicologia , Estimulação Luminosa/métodos , Desempenho Psicomotor/fisiologia , Percepção Visual/fisiologia , Adulto , Cognição/fisiologia , Feminino , Humanos , Masculino , Autorrelato , Adulto JovemRESUMO
INTRODUCTION: People who experience intrusive thoughts are at increased risk of developing hallucinatory experiences, as are people who have weak reality discrimination skills. No study has yet examined whether these two factors interact to make a person especially prone to hallucinatory experiences. The present study examined this question in a non-clinical sample. METHODS: Participants were 160 students, who completed a reality discrimination task, as well as self-report measures of cannabis use, negative affect, intrusive thoughts and auditory hallucination-proneness. The possibility of an interaction between reality discrimination performance and level of intrusive thoughts was assessed using multiple regression. RESULTS: The number of reality discrimination errors and level of intrusive thoughts were independent predictors of hallucination-proneness. The reality discrimination errors × intrusive thoughts interaction term was significant, with participants who made many reality discrimination errors and reported high levels of intrusive thoughts being especially prone to hallucinatory experiences. CONCLUSIONS: Hallucinatory experiences are more likely to occur in people who report high levels of intrusive thoughts and have weak reality discrimination skills. If applicable to clinical samples, these findings suggest that improving patients' reality discrimination skills and reducing the number of intrusive thoughts they experience may reduce the frequency of hallucinatory experiences.
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Cognição , Discriminação Psicológica , Alucinações , Pensamento , Adulto , Feminino , Humanos , Masculino , Autorrelato , Estudantes , Adulto JovemRESUMO
Proneness to unusual perceptual states - such as auditory or visual hallucinations - has been proposed to exist on a continuum in the general population, but whether there is a cognitive basis for such a continuum remains unclear. Intentional cognitive inhibition (the ability to wilfully control thoughts and memories) is one mechanism that has been linked to auditory hallucination susceptibility, but most evidence to date has been drawn from clinical samples only. Moreover, such a link has yet to be demonstrated over and above relations to other cognitive skills (source monitoring) and cognitive states (intrusive thoughts) that often correlate with both inhibition and hallucinations. The present study deployed two tests of intentional inhibition ability - the Inhibition of Currently Irrelevant Memories (ICIM) task and Directed Forgetting (DF) task - and one test of source monitoring (a source memory task) to examine how cognitive task performance relates to self-reported i) auditory hallucination-proneness and ii) susceptibility to intrusive thoughts in a non-clinical student sample (N = 76). Hierarchical regression analyses were used to assess the independent and combined contributions of task performance to proneness scores. ICIM performance but not DF or source memory scores were significantly related to both hallucination-proneness and intrusive thoughts. Further analysis suggested that intrusive thoughts may mediate the link between intentional inhibition skills and auditory hallucination-proneness, suggesting a potential pathway from inhibition to perception via intrusions in cognition. The implications for studying cognitive mechanisms of hallucination and their role in "continuum" views of psychosis-like experiences are discussed.
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Cognição/fisiologia , Função Executiva/fisiologia , Alucinações/psicologia , Inibição Psicológica , Memória/fisiologia , Transtornos Psicóticos/psicologia , Adolescente , Adulto , Feminino , Alucinações/fisiopatologia , Humanos , Masculino , Modelos Psicológicos , Testes Neuropsicológicos , Transtornos Psicóticos/fisiopatologia , Estudantes , Universidades , Adulto JovemRESUMO
BACKGROUND: A quick method of assessing readiness to change was needed for a major study of implementing screening and alcohol brief intervention in England. For this purpose, a Readiness Ruler that had been validated among a sample of male college students in the USA was adapted and applied to a sample of excessive drinkers in a general medical practice located in a deprived area of Gateshead, England. METHODS: 72 participants identified as excessive drinkers by health professionals completed a single-item Readiness Ruler, the 12-item Readiness to Change Questionnaire (RCQ) and the AUDIT questionnaire. RESULTS: In terms of concurrent validity, the relationships between the Readiness Ruler, on the one hand, and either stage of change allocation or a dimensional score derived from the RCQ, on the other hand, were highly significant but weaker than expected. When patients who endorsed the "maintenance" point on the Readiness Ruler were excluded from the analysis, the above relationships were considerably strengthened for reasons that are discussed. On this basis and with another small change, a final Readiness Ruler was developed. CONCLUSION: If the validity of the Readiness Ruler is confirmed in subsequent research, a quick and simple way of measuring readiness to change will be available for research or clinical work with alcohol brief interventions.
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Consumo de Bebidas Alcoólicas/psicologia , Consumo de Bebidas Alcoólicas/terapia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Psicoterapia Breve , Adulto , Inglaterra/epidemiologia , Medicina de Família e Comunidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores Socioeconômicos , Inquéritos e QuestionáriosRESUMO
BACKGROUND AND OBJECTIVES: When asked to evaluate faces of strangers, people with paranoia show a tendency to rate others as less trustworthy. The present study investigated the impact of arousal on this interpersonal bias, and whether this bias was specific to evaluations of trust or additionally affected other trait judgements. The study also examined the impact of eye gaze direction, as direct eye gaze has been shown to heighten arousal. METHODS: In two experiments, non-clinical participants completed face rating tasks before and after either an arousal manipulation or control manipulation. Experiment one examined the effects of heightened arousal on judgements of trustworthiness. Experiment two examined the specificity of the bias, and the impact of gaze direction. RESULTS: Experiment one indicated that the arousal manipulation led to lower trustworthiness ratings. Experiment two showed that heightened arousal reduced trust evaluations of trustworthy faces, particularly trustworthy faces with averted gaze. The control group rated trustworthy faces with direct gaze as more trustworthy post-manipulation. There was some evidence that attractiveness ratings were affected similarly to the trust judgements, whereas judgements of intelligence were not affected by higher arousal. LIMITATIONS: In both studies, participants reported low levels of arousal even after the manipulation and the use of a non-clinical sample limits the generalisability to clinical samples. CONCLUSIONS: There is a complex interplay between arousal, evaluations of trustworthiness and gaze direction. Heightened arousal influences judgements of trustworthiness, but within the context of face type and gaze direction.
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Nível de Alerta/fisiologia , Reconhecimento Facial/fisiologia , Fixação Ocular/fisiologia , Transtornos Paranoides/fisiopatologia , Percepção Social , Pensamento/fisiologia , Confiança , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
BACKGROUND: Auditory Hallucinations may arise from people confusing their own inner speech with external spoken speech. People with visual hallucinations (VH) may similarly confuse vivid mental imagery with external events. This paper reports two experiments exploring confusion between internal and external visual material. METHOD: Experiment 1 examined reality monitoring in people with psychosis; those with visual hallucinations (n = 16) and those without (n = 15). Experiment 2 used two non-clinical groups of people with high or low predisposition to VH (HVH, n = 26, LVH, n = 21). All participants completed the same reality monitoring task. Participants in Experiment 2 also completed measures of imagery. RESULTS: Psychosis patients with VH demonstrated biased reality monitoring, where they misremembered items that had been presented as words as having been presented as pictures. Patients without VH did not show this bias. In Experiment 2, the HVH group demonstrated the same bias in reality monitoring that psychosis patients with VH had shown. The LVH group did not show this bias. In addition, the HVH group reported more vivid imagery and particularly more negative imagery. CONCLUSIONS: Both studies found that people with visual hallucinations or prone-ness to such experiences confused their inner visual experiences with external images. Vivid imagery was also related to proneness to VH. Hence, vivid imagery and reality monitoring confusion could be contributory factors to understanding VH.
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Confusão/psicologia , Alucinações/psicologia , Imaginação , Transtornos Psicóticos/psicologia , Teste de Realidade , Adulto , Estudos de Casos e Controles , Feminino , Alucinações/complicações , Humanos , Masculino , Transtornos Psicóticos/complicações , Adulto JovemRESUMO
People with schizophrenia who hallucinate show impairments in reality monitoring (the ability to distinguish internally generated information from information obtained from external sources) compared to non-hallucinating patients and healthy individuals. While this may be explained at least in part by an increased externalizing bias, it remains unclear whether this impairment is specific to reality monitoring, or whether it also reflects a general deficit in the monitoring of self-generated information (internal source monitoring). Much interest has focused recently on continuum models of psychosis which argue that hallucination-proneness is distributed in clinical and non-clinical groups, but few studies have directly investigated reality monitoring and internal source monitoring abilities in healthy individuals with a proneness to hallucinations. Two experiments are presented here: the first (N = 47, with participants selected for hallucination-proneness from a larger sample of 677 adults) found no evidence of an impairment or externalizing bias on a reality monitoring task in hallucination-prone individuals; the second (N = 124) found no evidence of atypical performance on an internal source monitoring task in hallucination-prone individuals. The significance of these findings is reviewed in light of the clinical evidence and the implications for models of hallucination generation discussed.
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Córtex Auditivo/fisiopatologia , Alucinações/psicologia , Transtornos Psicóticos/psicologia , Adulto , Feminino , Humanos , Masculino , Teste de Realidade , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Análise e Desempenho de TarefasRESUMO
It is not only unclear why hallucinations in schizophrenia occur with different prevalence by modality, but also to what extent they do. Reliable prevalence estimates of hallucinations by modality in schizophrenia are currently lacking, particularly for non-auditory hallucinations. Studies have also tended to report lifetime, not point prevalence by modality. This study assessed the prevalence and co-occurrence of hallucinations, for both lifetime and point prevalence, across the auditory, visual, olfactory, and tactile modalities, in people diagnosed with chronic schizophrenia-spectrum disorders in Ireland (N=693) and Australia (N=218). Lifetime prevalence was 64-80% auditory, 23-31% visual, 9-19% tactile, and 6-10% olfactory. Past month prevalence was 23-27% auditory, 5-8% visual, 4-7% tactile, and 2% olfactory. The majority of participants had only hallucinated in one modality, with this nearly always being the auditory. Approximately one-third had hallucinated in two modalities, most commonly the auditory and visual. Most currently hallucinating patients also hallucinated in a single modality, again, nearly always the auditory. Whereas 30-37% of patients with lifetime auditory hallucinations had experienced visual hallucinations, 83-97% of patients with experience of visual hallucinations had experienced auditory hallucinations. These findings help delineate the modality distribution of hallucinations in schizophrenia, and provide an explanatory target for theoretical models.
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Alucinações/epidemiologia , Alucinações/psicologia , Percepção , Esquizofrenia/epidemiologia , Psicologia do Esquizofrênico , Adulto , Percepção Auditiva , Austrália/epidemiologia , Comorbidade , Feminino , Humanos , Irlanda/epidemiologia , Masculino , Pessoa de Meia-Idade , Percepção Olfatória , Prevalência , Percepção do Tato , Percepção VisualRESUMO
Cognitive models have suggested that auditory hallucinations occur when internal mental events, such as inner speech or auditory verbal imagery (AVI), are misattributed to an external source. This has been supported by numerous studies indicating that individuals who experience hallucinations tend to perform in a biased manner on tasks that require them to distinguish self-generated from non-self-generated perceptions. However, these tasks have typically been of limited relevance to inner speech models of hallucinations, because they have not manipulated the AVI that participants used during the task. Here, a new paradigm was employed to investigate the interaction between imagery and perception, in which a healthy, non-clinical sample of participants were instructed to use AVI whilst completing an auditory signal detection task. It was hypothesized that AVI-usage would cause participants to perform in a biased manner, therefore falsely detecting more voices in bursts of noise. In Experiment 1, when cued to generate AVI, highly hallucination-prone participants showed a lower response bias than when performing a standard signal detection task, being more willing to report the presence of a voice in the noise. Participants not prone to hallucinations performed no differently between the two conditions. In Experiment 2, participants were not specifically instructed to use AVI, but retrospectively reported how often they engaged in AVI during the task. Highly hallucination-prone participants who retrospectively reported using imagery showed a lower response bias than did participants with lower proneness who also reported using AVI. Results are discussed in relation to prominent inner speech models of hallucinations.
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Alucinações/fisiopatologia , Imaginação/fisiologia , Detecção de Sinal Psicológico/fisiologia , Percepção da Fala/fisiologia , Adolescente , Adulto , Percepção Auditiva , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Inner speech has been implicated in important aspects of normal and atypical cognition, including the development of auditory hallucinations. Studies to date have focused on covert speech elicited by simple word or sentence repetition, while ignoring richer and arguably more psychologically significant varieties of inner speech. This study compared neural activation for inner speech involving conversations ('dialogic inner speech') with single-speaker scenarios ('monologic inner speech'). Inner speech-related activation differences were then compared with activations relating to Theory-of-Mind (ToM) reasoning and visual perspective-taking in a conjunction design. Generation of dialogic (compared with monologic) scenarios was associated with a widespread bilateral network including left and right superior temporal gyri, precuneus, posterior cingulate and left inferior and medial frontal gyri. Activation associated with dialogic scenarios and ToM reasoning overlapped in areas of right posterior temporal cortex previously linked to mental state representation. Implications for understanding verbal cognition in typical and atypical populations are discussed.
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Encéfalo/fisiologia , Fala/fisiologia , Teoria da Mente/fisiologia , Pensamento/fisiologia , Mapeamento Encefálico , Dominância Cerebral/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/fisiologiaRESUMO
Cognitive behavioral therapy (CBT) for voice-hearing (i.e., auditory verbal hallucinations; AVH) has, at best, small to moderate effects. One possible reason for this limited efficacy is that current CBT approaches tend to conceptualize voice-hearing as a homogenous experience in terms of the cognitive processes involved in AVH. However, the highly heterogeneous nature of voice-hearing suggests that many different cognitive processes may be involved in the etiology of AVH. These heterogeneous voice-hearing experiences do, however, appear to cluster into a set of subtypes, opening up the possibility of tailoring treatment to the subtype of AVH that a voice-hearer reports. In this paper, we (a) outline our rationale for tailoring CBT to subtypes of voice-hearing, (b) describe CBT for three putative subtypes of AVH (inner speech-based AVH, memory-based AVH, and hypervigilance AVH), and (c) discuss potential limitations and problems with such an approach. We conclude by arguing that tailoring CBT to subtypes of voice-hearing could prove to be a valuable therapeutic development, which may be especially effective when used in early intervention in psychosis services.
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BACKGROUND AND OBJECTIVES: People who experience auditory hallucinations tend to show weak reality discrimination skills, so that they misattribute internal, self-generated events to an external, non-self source. We examined whether inducing negative affect in healthy young adults would increase their tendency to make external misattributions on a reality discrimination task. METHODS: Participants (N = 54) received one of three mood inductions (one positive, two negative) and then performed an auditory signal detection task to assess reality discrimination. RESULTS: Participants who received either of the two negative inductions made more false alarms, but not more hits, than participants who received the neutral induction, indicating that negative affect makes participants more likely to misattribute internal, self-generated events to an external, non-self source. LIMITATIONS: These findings are drawn from an analogue sample, and research that examines whether negative affect also impairs reality discrimination in patients who experience auditory hallucinations is required. CONCLUSIONS: These findings show that negative affect disrupts reality discrimination and suggest one way in which negative affect may lead to hallucinatory experiences.
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Afeto/fisiologia , Alucinações/psicologia , Teste de Realidade , Detecção de Sinal Psicológico/fisiologia , Estimulação Acústica , Adolescente , Adulto , Ansiedade/psicologia , Depressão/psicologia , Feminino , Humanos , Solidão/psicologia , Masculino , Autorrelato , Adulto JovemRESUMO
Despite the recent proliferation of scientific, clinical, and narrative accounts of auditory verbal hallucinations (AVHs), the phenomenology of voice hearing remains opaque and undertheorized. In this article, we outline an interdisciplinary approach to understanding hallucinatory experiences which seeks to demonstrate the value of the humanities and social sciences to advancing knowledge in clinical research and practice. We argue that an interdisciplinary approach to the phenomenology of AVH utilizes rigorous and context-appropriate methodologies to analyze a wider range of first-person accounts of AVH at 3 contextual levels: (1) cultural, social, and historical; (2) experiential; and (3) biographical. We go on to show that there are significant potential benefits for voice hearers, clinicians, and researchers. These include (1) informing the development and refinement of subtypes of hallucinations within and across diagnostic categories; (2) "front-loading" research in cognitive neuroscience; and (3) suggesting new possibilities for therapeutic intervention. In conclusion, we argue that an interdisciplinary approach to the phenomenology of AVH can nourish the ethical core of scientific enquiry by challenging its interpretive paradigms, and offer voice hearers richer, potentially more empowering ways to make sense of their experiences.
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Cultura , Alucinações/psicologia , Meio Social , Comportamento Cooperativo , Alucinações/etnologia , Alucinações/terapia , Ciências Humanas , Humanos , Modelos Psicológicos , Pesquisa , Ciências SociaisRESUMO
AIMS: To test two central assumptions of the Transtheoretical Model (TTM) regarding recovery from alcohol problems: (i) individuals making a forward transition from pre-action to action stages will show greater drinking improvements than those remaining in pre-action stages; and (ii) individuals remaining in pre-action stages will not demonstrate improvements in drinking outcomes. DESIGN AND SETTING: Large, multi-centre, randomized controlled trial of treatment for alcohol problems [United Kingdom Alcohol Treatment Trial (UKATT)]. MEASUREMENTS: Stage of change, drinks per drinking day and percentage days abstinent at baseline, 3- and 12-month follow-ups. FINDINGS: In support of TTM assumption 1, improvements in drinking outcomes were consistently greater among clients who showed a forward stage transition (Cohen's d = 0.68) than among those who did not (d = 0.10). Two tests of assumption 2 showed a significant improvement in drinking outcomes in non-transition groups, inconsistent with the TTM; one test showed a significant deterioration and the other showed equivalent drinking outcomes across time. An explanation is offered as to why, under the relevant assumption of the TTM, clients in non-transition groups showed small changes in drinking outcomes. CONCLUSIONS: In contrast to a previous study by Callaghan and colleagues, our findings largely support the TTM account of recovery from alcohol problems in treatment. The discrepancy can be explained by the use in our study of a more reliable and valid method for assigning stage of change.