Internal versus external auditory hallucinations in schizophrenia: symptom and course correlates

Introduction. The auditory hallucinations associated with schizophrenia are phenomenologically diverse. “External” hallucinations classically have been considered to reflect more severe psychopathology than “internal” hallucinations, but empirical support has been equivocal.

Methods. We examined associations of “internal” versus “external” hallucinations with (1) other characteristics of the hallucinations, (2) severity of other symptoms and (3) course of illness variables, in a sample of 97 stable outpatients with schizophrenia or schizoaffective disorder who experienced auditory hallucinations.

Results. Patients with internal hallucinations did not differ from those with external hallucinations on severity of other symptoms. However, they reported their hallucinations to be more emotionally negative, distressing and long-lasting, less controllable and less likely to remit over time. They also were more likely to experience voices commenting, conversing or commanding. However, they also were more likely to have insight into the self-generated nature of their voices. Patients with internal hallucinations were not older, but had a later age of illness onset.

Conclusions. Differences in characteristics of auditory hallucinations are associated with differences in other characteristics of the disorder, and hence may be relevant to identifying subgroups of patients that are more homogeneous with respect to their underlying disease processes.     

Is this my voice or yours? The role of emotion and acoustic quality in self-other voice discrimination in schizophrenia

Introduction: Impairments in self-other voice discrimination have been consistently reported in schizophrenia, and associated with the severity of auditory verbal hallucinations (AVHs). This study probed the interactions between voice identity, voice acoustic quality, and semantic valence in a self-other voice discrimination task in schizophrenia patients compared with healthy subjects. The relationship between voice identity discrimination and AVH severity was also explored.

Methods: Seventeen chronic schizophrenia patients and 19 healthy controls were asked to read aloud a list of adjectives characterised by emotional or neutral content. Participants’ voice was recorded in the first session. In the behavioural task, 840 spoken words differing in identity (self/non-self), acoustic quality (undistorted/distorted), and semantic valence (negative/positive/neutral) were presented. Participants indicated if the words were spoken in their own voice, another person’s voice, or were unsure.

Results: Patients were less accurate than controls in the recognition of self-generated speech with negative content only. Impaired recognition of negative self-generated speech was associated with AVH severity (“voices conversing”).

Conclusions: These results suggest that abnormalities in higher order processes (evaluation of the salience of a speech stimulus) modulate impaired self-other voice discrimination in schizophrenia. Abnormal processing of negative self-generated speech may play a role in the experience of AVH.     

Inhibitory deterioration may contribute to hallucinations in Alzheimer's disease

Introduction. Although delusions and hallucinations are relatively common symptoms in individuals with Alzheimer's disease (AD), very little is known regarding underlying mechanisms. We examined whether these manifestations could be underpinned by psychological distress and executive impairments.

Methods. Thirty-one participants with probable mild AD and 33 healthy older adults were administered a neuropsychological and clinical battery assessing delusions, hallucinations, anxiety, depression, episodic memory and executive functions (shifting, updating and inhibition).

Results. Prevalence of delusions and hallucinations were significantly higher in AD participants compared to control participants. Further, hallucinations in AD participants were significantly correlated with poor inhibition, with the latter uniquely predicting the former, as compared to other variables. In addition, hallucinations in AD participants were associated with depression, a relationship that was further mediated by inhibition.

Conclusion. Hallucinations in individuals with AD seem to be related to difficulties suppressing irrelevant thoughts, resulting in these irrelevant thoughts becoming confused with ongoing reality.     

Secular trends in cranial morphological traits: a socioeconomic perspective of change and sexual dimorphism in North Americans 1849–1960

Background: The human body has undergone significant changes in stature and other areas, which reflect secular trends associated with socioeconomics.

Aim: To analyse cranial morphological traits for deciphering if they are subject to secular trends.

Subjects and methods: Two documented skeletal collections were sampled for a total of 525 individuals from 1849–1960. Cranial morphological traits were scored and input into time series statistics (logistic regression).

Results: In females, nuchal crests have enlarged, while glabella has decreased. In males, supraorbital margins have dulled, while glabella decreased. Sexual dimorphism increased in supraorbital margins.

Conclusion: The patterns in the data here reflect those found in other areas of the skeleton, namely height, as regards to secular trends. These findings can be extended to stature and cranial changes that parallel socioeconomic trends during the Industrial Revolution, antebellum period and after.     

Preliminary study of a rehabilitation program based on attentional processes to treat auditory hallucinations

Introduction: Despite the effectiveness of pharmacological treatment, residual hallucinations do not completely resolve in some medicated patients. The aim of this study was to investigate the efficacy of attention training for reducing hallucinations in individuals with psychosis.

Methods: A randomised controlled trial was performed in which 20 individuals suffering auditory hallucinations received auditory stimulation similar to their internal voices, which was integrated into the RehaCom program of attention training. An equal number of individuals suffering auditory hallucinations did not receive this training. Cognitive and symptomatological variables were evaluated before and after the intervention period in both groups.

Results: Only data of 16 subjects were analysed. Auditory hallucinations no longer occurred by the end of the training program in five of eight individuals, whereas their frequency, intensity and negative content and associated anxiety were significantly reduced in the remaining three. No changes in hallucinations were observed in the control group. Attentional processes and executive functions were significantly better in patients who underwent the training than in those who did not at the end of the intervention period.

Conclusions: Attention training can help people with auditory hallucinations develop an ability to ignore them, which can reduce or eliminate them entirely.     

Isometric torso muscle endurance profiles in adolescents aged 15–18: normative values for age and gender differences

Objective: The aim of this study was to establish normative values for torso muscle endurance in adolescents aged 15–18 years. It was hypothesized that torso endurance profiles of adolescents differs between males and females and between adolescents and adults.

Background: Decreased torso muscle endurance has been identified as a potential personal risk factor for low back pain development in both adolescents and later years together with being detrimental for athletic performance.

Design: Measurement of torso muscle endurance, established through four tests performed in random order in a healthy adolescent population.

Setting: High school in Novi Sad, Province of Vojvodina, Republic of Serbia.

Methods: Two hundred and ninety-four adolescents from one high school (178 males and 116 females) were grouped into four age strata. Selected isometric torso muscle endurance tests were: Biering-Sørensen test for extensor endurance; Flexor endurance test; right and left Side Bridge tests. The mean, ratio, standard deviation and 25th, 50th and 75th percentile scores were determined for each gender/age strata.

Results and conclusion: Males had higher lateral torso endurance than females. Adolescents in general demonstrate their peak lifetime endurance as they appear more endurable than children and comparable adult groups. These data of endurance times, their ratios and percentiles in healthy normal subjects form a database bridging existing data for children and adults that may be useful for guiding training and rehabilitation.     

Body image,body dissatisfaction and weight status in children from Emilia-Romagna (Italy): comparison between immigrant and native-born

Background: Cross-sectional study among immigrant and native children from Emilia-Romagna (Italy).

Aim: The purpose of the present study was to examine the relative contribution of weight status, ethnicity and sex on body dissatisfaction in a sample of children from Emilia-Romagna (Italy).

Subjects and methods: Primary school children (226 immigrants and 1206 Italians) aged 6–11 years were measured: immigrant children were divided into Asians, Africans, Latin Americans and East Europeans. Height and weight were measured and Body Mass Index (BMI) was calculated. Body image perception was assessed using Body Silhouette Charts. A body dissatisfaction score (BDS) was derived by subtracting the "ideal self" from the "self" score.

Results: Weight status disorders were higher in immigrants than in native-born males; Italian females had higher prevalence of underweight and overweight and lower prevalence of obesity than immigrants peers. BDS rose with the increase of weight status categories.

Conclusions: Awareness of body image size and increasing body dissatisfaction with higher weight status is established in childhood, regardless of ethnicity and gender.     

The Cortical Hyperexcitability Index (CHi): a new measure for quantifying correlates of visually driven cortical hyperexcitability

Introduction. Aberrations of visual experience, including visual hallucinations and visual distortions, are known to be associated with increased cortical hyperexcitability. As a consequence, the presence, intensity and frequency of certain experiences may well be indicative of an underlying increase in cortical hyperexcitability.

Methods. The current study presents a new proxy measure of cortical hyperexcitability, the Cortical Hyperexcitability Index (CHi). Two hundred and fifty healthy participants completed the CHi with the results subjected to exploratory factor analysis (EFA).

Results. The EFA revealed a three-factor model as the most parsimonious solution. The three factors were defined as: (1) heightened visual sensitivity and discomfort; (2) negative aura-type visual aberrations; and (3) positive aura-type visual aberrations. The identification of three factors suggests that multiple mechanisms underlie the notion of cortical hyperexcitability, providing researchers with new and greater precision in delineating these underlying features.

Conclusions. The factorial structure of the CHi and the increased precision could aid the interpretation of findings from neuroscientific (i.e., brain imaging/stimulation) examinations of cortical processes underlying aberrant perceptions across a host of clinical, neurological and pathological conditions. As a consequence, the CHi is a useful and comprehensive proxy measure of cortical hyperexcitability with considerable scientific and clinical utility.     

Cued fluency protocol reveals dynamic symptomatic-dependent processes of goal-directed behaviours in schizophrenia

Introduction. Differential impairments of willed actions and routine behaviours are the subject of many studies into schizophrenia. These impairments in generating and controlling goal-directed behaviours are reported in studies showing the effect of cueing in cognitive or motor tasks in people with schizophrenia. The aim of this study was to assess the performance of people with schizophrenia in a cued fluency protocol reworked to fit the concept of goal-directed behaviour. The extent to which results could be better explained by goal-directed generation issues, according to a symptomatic framework, than by semantic retrieval or semantic processing impairments, was also investigated.

Methods. We compared the performance of 43 individuals with schizophrenia to a control group of 26 participants. Participants were assessed with neuropsychological tests. The dominance of positive and negative symptoms, and apathetic profile, were also evaluated. All participants completed a cued fluency protocol.

Results. Despite a significant improvement, not all people with schizophrenia exhibited equal cueing benefits. The participants with negative symptom dominance appeared to benefit more from cueing, even though their baseline performance was lower.

Conclusions. These results suggest that, in addition to semantic memory impairments, some cognitive tasks may be more broadly influenced by difficulties in generating goal-directed behaviours.     

Hallucinations and inhibitory functioning in healthy young adults with high and low levels of hypomanic personality traits

Introduction. Hallucinations in schizophrenia and hallucination proneness in healthy young adults are associated with a common cognitive mechanism, namely impaired inhibitory control. Hallucinatory-like experiences also seem related to hypomanic symptoms in non-clinical participants; however, the mechanisms involved are unknown. We sought to examine self-reported hallucinatory/anomalous perceptual experiences in students selected for high versus low levels of hypomanic personality traits, and whether hypomania is characterised by deficient inhibitory control.

Method. Undergraduate students with either high (n = 26) or low (n = 28) scores on the Hypomanic Personality Scale-Revised (HPS-20) were compared on: (1) the Launay Slade Hallucination Scale-Revised (LSHS-R), a measure of hallucination proneness, (2) the Cardiff Anomalous Perceptions Scale (CAPS) and (3) the Inhibition of Currently Irrelevant Memories (ICIM) task, an index of intentional inhibition.

Results. The high HPS group had higher total scores, as well as higher frequency (on CAPS only), intrusiveness and distress (CAPS) scores compared to the low HPS group. They also produced significantly more false alarms on the second run of the ICIM task than the low hypomania traits group.

Conclusions. Frequent, intrusive and distressing perceptual anomalies and proneness to hallucinations tend to occur in healthy individuals with hypomanic personality traits and may be associated with transient difficulties with inhibitory control. Inhibitory control may be a cognitive marker of vulnerability to hallucinations across diagnostic boundaries.     

Cognition and social cognition in non-psychotic siblings of patients with schizophrenia

Introduction. Deficits in Social Cognition are common in people with schizophrenia. However, it is not clear if these deficits are a vulnerability marker and whether they are independent to cognitive difficulties. This study investigates these two issues in individuals with a genetic liability to psychosis.

Methods. Twenty-one healthy siblings of patients with schizophrenia were compared with 21 healthy individuals on a range of cognitive and social cognitive measures. Significant differences in cognitive domains were controlled for when comparing the two groups on measures of social cognition.

Results. Siblings of people with schizophrenia performed significantly worst on tests of theory of mind and social perception but not on affect recognition. Scores on tests of executive function, processing speed and general IQ were also lower in the sibling group. When controlled for differences in cognitive tests, the two groups still retained significant differences in theory of mind and social perception. However, executive function significantly contributed to theory of mind and processing speed to social perception differences.

Conclusions. These results further suggest that difficulties in some domains of social cognition are associated with a genetic vulnerability for schizophrenia. In these areas, cognitive difficulties account only partially for social cognition problems suggesting that these two domains may represent relatively independent liability factors.     

Effort discounting and its association with negative symptoms in schizophrenia

Introduction. Deficits in the initiation and persistence of goal-directed behaviour are key aspects of schizophrenia. In this study, the association between these motivational deficits and discounting of reward value in function of increasing physical effort costs was investigated.

Methods. Effort-based decision-making was investigated in 40 patients with a DSM-IV diagnosis of schizophrenia and 30 age- and sex-matched healthy control subjects by means of an effort discounting task. To assess negative symptom severity, we made use of the Scale for the Assessment of Negative Symptoms as well as objective measurements of hedonic response to stimuli and motor activity levels.

Results. Patients as well as control subjects discounted the subjective value of rewards significantly with increasing physical effort costs. However, we failed to find a difference in the discounting curves between patients and controls. Furthermore, effort discounting was not associated with any of the negative symptoms measures.

Conclusions. Physical effort discounting was not found to be associated with motivational symptoms in schizophrenia if other decision costs are constant. However, recent findings show that more cognitive effort and/or an interaction between effort and other decision costs (e.g. temporal delay or uncertainty) are associated with negative symptoms in schizophrenia. This should be investigated further in future research.     

Preserved priming effect in individuals with schizophrenia: cues towards rehabilitation

Introduction. Individuals with schizophrenia and affective disorders show relatively intact implicit memory as compared to declarative memory. Implicit memory is usually assessed with skill learning and priming tasks. Whereas priming is thought to involve storage changes in the posterior neocortex, skill learning is thought to rely more on the corticostriatal pathway. Since frontostriatal and frontotemporal dysfunctions are, respectively, found in schizophrenia and affective disorders, we hypothesised that individuals with schizophrenia and first-episode psychosis would exhibit disturbances in skill learning, but not priming.

Methods. Thirty-five patients (11 first-episode psychosis; 11 schizophrenia; 13 affective disorders) and 10 controls completed a procedural learning and priming task. Participants had to identify fragmented images throughout five training sessions. The improvement of the threshold at which the images could be identified between the first and last session was used as an index of procedural learning. In a final session, the identification thresholds for old and new images were compared to assess the priming effect.

Results. Whereas individuals with schizophrenia and first-episode psychosis showed impaired skill learning, the priming effect was similar in all groups.

Conclusion. Even though some aspects of learning and memory are affected in schizophrenia, our results suggest that the posterior cortical pathway remains efficient at modulating the priming effect. This intact ability could be used to guide the elaboration of new rehabilitation programmes.     

Effects of cognitive remediation therapy on neurocognition and negative symptoms in schizophrenia: an Italian naturalistic study

Introduction: Cognitive remediation therapy (CRT) has been reported to positively affect neurocognitive processes among patients with schizophrenia; however, the degree to which changes in cognition is linked to improved clinical symptoms, remains poorly understood. The current study aimed to investigate whether cognitive gains were associated to improvements in negative symptoms’ severity in patients with schizophrenia living in two Italian psychiatric facilities.

Methods: Patients with a diagnosis of schizophrenia were consecutively assigned to CRT (n?=?33) and compared with an historical control group (n?=?28). Assessments were performed at baseline and post-treatment using a neuropsychological battery (Trail Making Test A and B, Self-Ordered Pointing Task, California Verbal Learning Test), along with clinical and functioning measures.

Results: Visual attention (TMT-A score change) was found as the only significant predictor of improvement in negative symptoms subscale of the Positive and Negative Syndrome Scale. Furthermore, a mediation path analysis confirmed that better performance in visual attention acts as mediator of the positive association between CRT intervention and lower post-treatment negative symptoms score.

Conclusions: CRT can have a positive impact on a measure of visual attention in patients with schizophrenia and on negative symptoms reduction that is mediated by this significant intervention effect.     

Parturition lines in modern human wisdom tooth roots: do they exist,can they be characterized and are they useful for retrospective determination of age at first reproduction and/or inter-birth intervals?

Background: Parturition lines have been described in the teeth of a number of animals, including primates, but never in modern humans. These accentuated lines in dentine are comprised of characteristic dark and light component zones.

Aim: The aim of this study was to review the physiology underlying these lines and to ask if parturition lines exist in the third molar tooth roots of mothers known to have had one or more children during their teenage years.

Methods: Brief retrospective oral medical obstetric histories were taken from four mothers and compared with histological estimates for the timing of accentuated markings visible in longitudinal ground sections of their wisdom teeth.

Results: Evidence of accentuated markings in M3 root dentine matched the age of the mother at the time their first child was born reasonably well. However, the dates calculated for inter-birth intervals did not match well.

Conclusions: Parturition lines corresponding to childbirth during the teenage years can exist in human M3 roots, but may not always do so. Without a written medical history it would not be possible to say with confidence that an accentuated line in M3 root dentine was caused by stress, illness or was a parturition line.     

Modelling foetal growth in a bi-ethnic sample: results from the Born in Bradford (BiB) birth cohort

Background: Attempts to explain the increased risk for metabolic disorders observed in South Asians have focused on the “South Asian” phenotype at birth and subsequent post-natal growth, with little research on pre-natal growth.

Aim: To identify whether divergent growth patterns exist for foetal weight, head (HC) and abdominal circumferences (AC) in a sample of Pakistani and White British foetuses.

Subjects and methods: Models were based on 5553 (weight), 5154 (HC) and 5099 (AC) foetuses from the Born in Bradford birth cohort. Fractional polynomials and mixed effects models were employed to determine growth patterns from ～15 weeks of gestation-birth.

Results: Pakistani foetuses were significantly smaller and lighter as early as 20 weeks. However, there was no ethnic difference in the growth patterns of weight and HC. For AC, Pakistani foetuses displayed a trend for reduced growth in the final trimester.

Conclusion: As the pattern of weight and HC growth was not significantly different during the period under investigation, the mechanism culminating in the reduced Pakistani size at birth may act earlier in gestation. Reduced AC growth in Pakistanis may represent reduced growth of the visceral organs, with consequences for post-natal liver metabolism and renal function.     

The role of physical activity,body mass index and maturity status in body-related perceptions and self-esteem of adolescents

Background: Adolescence represents a transitional period which is marked by physical, social and psychological changes. Changes in body shape and physical activity especially alter and shape the psychological well-being of adolescents.

Aim: The purpose of this study was to determine the role of physical activity level, body mass index and maturity status in body-related perception and self-esteem of 11–18 years old adolescents.

Subjects and methods: A total of 1012 adolescents participated in this study. The “Social Physique Anxiety Scale”, “Body Image Satisfaction Scale”, “Physical Self-Perception Profile for Children” and “Rosenberg Self-Esteem Inventory” were administered. Physical activity level and body mass index were assessed using the “Physical Activity Questionnaire” and “Bioelectrical Impedance Analyzer”, respectively.

Results: Regression analysis indicated that body mass index was the only predictor of perceived body attractiveness, social physique anxiety, body image satisfaction and self-esteem for female adolescents. For male adolescents, both physical activity and body mass index were correlated with perceived body attractiveness and social physique anxiety. Pubertal status were not correlated with self-esteem and body-related perceptions for both males and females adolescents.

Conclusion: In summary, body mass index and physical activity plays an important role in body-related perceptions and self-esteem of adolescents.     

Systematic overview of neuroanatomical differences in ADHD: Definitive evidence

Objectives: This article seeks to identify neuroanatomical differences in ADHD through an overview of systematic reviews that report encephalic differences compared to a control group in volume, area, activation likelihood or chemical composition.

Methods: We conducted a systematic search using Cochrane guidelines and PRISMA criteria in PubMed, Scopus, Web of Science, Cochrane Database of Systematic Reviews and Database of Abstracts of Reviews of Effects.

Results: Results revealed broad encephalic involvement that includes a functional frontal and cingulate hypoactivation and structural differences in corpus callosum, cerebellum and basal nuclei.

Conclusions: ADHD symptoms might be due to a multi-network unbalanced functioning hypothesis.