Dimensional structure of bodily panic attack symptoms and their specific connections to panic cognitions, anxiety sensitivity and claustrophobic fears.

BACKGROUND: Previous studies of the dimensional structure of panic attack symptoms have mostly identified a respiratory and a vestibular/mixed somatic dimension. Evidence for additional dimensions such as a cardiac dimension and the allocation of several of the panic attack symptom criteria is less consistent. Clarifying the dimensional structure of the panic attack symptoms should help to specify the relationship of potential risk factors like anxiety sensitivity and fear of suffocation to the experience of panic attacks and the development of panic disorder. METHOD: In an outpatient multicentre study 350 panic patients with agoraphobia rated the intensity of each of the ten DSM-IV bodily symptoms during a typical panic attack. The factor structure of these data was investigated with nonlinear confirmatory factor analysis (CFA). The identified bodily symptom dimensions were related to panic cognitions, anxiety sensitivity and fear of suffocation by means of nonlinear structural equation modelling (SEM). RESULTS: CFA indicated a respiratory, a vestibular/mixed somatic and a cardiac dimension of the bodily symptom criteria. These three factors were differentially associated with specific panic cognitions, different anxiety sensitivity facets and suffocation fear. CONCLUSIONS: Taking into account the dimensional structure of panic attack symptoms may help to increase the specificity of the associations between the experience of panic attack symptoms and various panic related constructs.

Precomputed Radiative Heat Transport for Efficient Thermal Simulation.

Architectural design and urban planning are complex design tasks. Predicting the thermal impact of design choices at interactive rates enhances the ability of designers to improve energy efficiency and avoid problematic heat islands while maintaining design quality. We show how to use and adapt methods from computer graphics to efficiently simulate heat transfer via thermal radiation, thereby improving user guidance in the early design phase of large-scale construction projects and helping to increase energy efficiency and outdoor comfort. Our method combines a hardware-accelerated photon tracing approach with a carefully selected finite element discretization, inspired by precomputed radiance transfer. This combination allows us to precompute a radiative transport operator, which we then use to rapidly solve either steady-state or transient heat transport throughout the entire scene. Our formulation integrates time-dependent solar irradiation data without requiring changes in the transport operator, allowing us to quickly analyze many different scenarios such as common weather patterns, monthly or yearly averages, or transient simulations spanning multiple days or weeks. We show how our approach can be used for interactive design workflows such as city planning via fast feedback in the early design phase.

Long-term cognitive and emotional consequences of mild traumatic brain injury.

BACKGROUND: The objective of this study was to investigate long-term cognitive and emotional sequelae of mild traumatic brain injury (mTBI), as previous research has remained inconclusive with respect to their prevalence and extent. METHOD: Thirty-three individuals who had sustained mTBI on average 6 years prior to the study and 33 healthy control subjects were matched according to age, gender and education. Structural brain damage at time of testing was excluded by magnetic resonance imaging (MRI). A comprehensive neuropsychological test battery was conducted to assess learning, recall, working memory, attention and executive function. Psychiatric symptoms were assessed by the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I) and the Beck Depression Inventory (BDI). Possible negative response bias was ruled out by implementing the Word Memory Test (WMT). RESULTS: The mTBI individuals had significant impairments in all cognitive domains compared to the healthy control subjects. Effect sizes of cognitive deficits were medium to large, and could not be accounted for by self-perceived deficits, depression, compensation claims or negative response bias. BDI scores were significantly higher in the patient group, and three patients fulfilled DSM-IV criteria for a mild episode of major depression. CONCLUSIONS: Primarily, well-recovered individuals who had sustained a minor trauma more than half a decade ago continue to have long-term cognitive and emotional sequelae relevant for everyday social and professional life. mTBI may lead to a lasting disruption of neurofunctional circuits not detectable by standard structural MRI and needs to be taken seriously in clinical and forensic evaluations.

The Chemical Odor Sensitivity Scale: reliability and validity of a screening instrument for idiopathic environmental intolerance.

OBJECTIVE: The objective of this study was to examine the psychometric qualities of a brief screening measure for idiopathic environmental intolerance (IEI), the Chemical Odor Sensitivity Scale (COSS). METHODOLOGY: The COSS was administered together with other measures of environmental sensitivity, IEI, and symptom scales in large samples (students, individuals with IEI, and individuals without IEI). RESULTS: The COSS achieved high internal consistency (.88 < or = Cronbach's alpha < or = .96) and good factorial, convergent, and discriminant validity across diverse samples. In a longitudinal sample, the COSS and other IEI features were stable across time. According to receiver operating characteristic analyses, the COSS performs adequately in screening individuals likely to meet case criteria for IEI. CONCLUSIONS: The favorable psychometric qualities of the COSS recommend the scale as a useful tool both for assessing self-reported chemical odor sensitivity as a vulnerability marker and for screening for IEI.

Deficient interference control during working memory updating in adults with ADHD: An event-related potential study.

OBJECTIVE: Little is known about the underlying mechanisms of poor working memory (WM) performance of adults with attention deficit hyperactivity disorder (ADHD). This study investigates interference and load effects during WM updating by use of event-related potentials. METHOD: Forty ADHD patients and 41 controls performed verbal n-back tasks under conditions of low and high WM load. Intrusion probes, i.e., lures, were implemented to challenge interference control abilities during WM processing. RESULTS: Stimulus-dependent N200 amplitude modulation and behavioral performance in lure trials were reduced in adults with ADHD compared to healthy controls. Also, P300 amplitudes tended to be less sensitive to WM load in patients with ADHD. CONCLUSION: Our findings provide electrophysiological evidence for inaccurate discrimination of stimulus categories. Particularly, deficient interference control may lead to overt WM deficits in adult subjects with ADHD. SIGNIFICANCE: The current findings contribute to a deeper understanding of the neural substrates of executive dysfunction in adult ADHD, focusing on the domain of WM.

Error-correcting behavior in schizophrenic patients.

According to Frith (1987) the positive symptoms of schizophrenic patients result from an impaired central monitoring of their own actions. For motor behavior, this impairment implies deficient corrections of erroneous movements. Several studies found that schizophrenic patients did correct erroneous movements less frequently than various control groups. In these studies, movement errors were induced by instructing subjects to alternate between moving a joystick towards a target or away from it. In our study, 27 chronic schizophrenic patients, 27 healthy and 18 alcoholic controls were subjected to a similar task. Spatial and symbolic compatibility between stimuli and responses were varied in order to induce errors. Schizophrenic patients responded more slowly and took more time to reverse wrong movements than both control groups. They did not show fewer error corrections or increased correction latencies. These results did not support the supposed deficit in central monitoring of action. Schizophrenic patients exhibited more short latency movements with multiple changes of movement direction than the control groups. This may indicate a failure to inhibit the initiation of competing responses.

Reaction time paradigms in subjects at risk for schizophrenia.

Deviant response patterns in experimental reaction time paradigms in schizophrenic probands are well documented. Although simple reaction times are strongly influenced by the current psychopathological status of the proband (e.g. florid psychotic patients versus remitted patients) these influences are less clear for measures obtained from more complex reaction time paradigms. These include the crossover paradigm (reaction time to stimuli presented after constant preparatory intervals in comparison to reaction time to stimuli presented after irregular preparatory intervals) and the modality shift paradigm (reaction time to a stimulus (light or tone) when the modality of the stimulus on the preceding trial was the same compared to when it was different). It is not clear if these peculiarities of response patterns occur as a consequence of the disease or if they represent vulnerability markers for schizophrenia. Both crossover reaction time and modality shift reaction time paradigms were applied to 56 drug free schizophrenics, 45 healthy siblings of these patients and 68 healthy controls. The results indicate that retarded reaction times and the occurrence of the crossover effect as well as of the modality shift effect distinguish schizophrenics and controls. Healthy siblings of schizophrenics differed from healthy controls with regard to the crossover effect but not with regard to the modality shift effect. Therefore only the crossover effect represents a vulnerability marker for schizophrenia. Correlations between the modality shift and the crossover effect revealed strong correlations in the schizophrenic group only.

The patient rejection scale: cross-cultural consistency.

The Patient Rejection Scale, which was developed to assess rejecting feelings of family members toward mental patients, was administered to a sample of 80 relatives living with schizophrenic patients in the Federal Republic of Germany. In spite of the cross-cultural differences involved, the response distributions of the German sample and a New York City sample of families were almost identical. The findings are discussed in the context of "expressed emotions" research.

Neuropsychological indicators of the vulnerability to schizophrenia.

Schizophrenia is associated with enduring deficits in neuropsychological functioning. It is widely undecided if the various aspects of neuropsychological impairment are a consequence of the disorder or if they are also present premorbidly and in populations at increased risk for schizophrenia (vulnerability markers). Neuropsychological deficits in healthy relatives of schizophrenic patients who are at an elevated risk for schizophrenia and who did not yet pass the period of risk would indicate that these deficits are vulnerability markers. This hypothesis was tested for three neuropsychological paradigms which have been proven to distinguish schizophrenic patients from controls. 33 siblings of drug-free schizophrenic probands revealed deficits has compared to 33 matched healthy controls in a blurred single target version of the Continuous Performance Test and in a multiple item version of the Span of Apprehension Test but not so in less difficult versions of both tests or in the time needed to react to stimuli with shifting modality.

An event-related brain potential substrate of disturbed response monitoring in paranoid schizophrenic patients.

Response monitoring in schizophrenic patients and healthy controls was assessed by measuring performance and event-related brain potentials in the flanker priming task. Three visual-context conditions were construed: Flankers and targets pointed either into the same direction or into different directions. Stimuli without any response assignment were used as flankers in the neutral context condition. The schizophrenic patients were further subdivided into paranoid (n = 19) and nonparanoid (n = 10) patients and compared with healthy controls (n = 18). Performance scores revealed that the flankers induced a similar degree of distraction by visual context in all 3 groups. Although the schizophrenic patients showed normal error correction performance, the error negativity (NE) was significantly reduced in paranoid schizophrenic patients. The attenuation of the NE possibly reflects disturbed response monitoring in these patients.

Self assessment of social competence in situations with and without alcohol by female alcoholics in treatment.

Female alcoholic in-patients (N = 156) were asked during a three months treatment to rate the degree of discomfort they expected (a) in situations demanding assertiveness, but not involving rejection of alcoholic beverages and (b) in situations characterized by social temptation to drink. Correlations of ratings with age, duration of problem drinking, mean ethanol consumption per day or length of education were insignificant. Actual experience with social temptation situations in the past did not influence the rating. A principal Component Analysis showed that ratings of discomfort in general social situations and in alcohol related social situations are largely unrelated. The result of partially independent appraisals of general and alcohol related assertiveness suggests that both should be assessed independently, and generalizations from one to the other might be misleading.

[An alcohol contact program: training for increased security of alcoholics in trial situations]. / Das Alkoholkontaktprogramm: ein Training zur Erhohung der sicherheit Alkoholkranker in Versuchungs-Situationen.

Alcoholics who have taken the decision to abstain are known to develop, partially out of fear of a relapse, an almost phobic avoidance behaviour towards situations where alcoholic drinks may be proffered. Starting from this observation a four-hour behavioural programme, involving modeling and the discussion of appropriate behaviour, was developed to prepare patients for such situations. The two methods resulted in equally highly significant improvement, as measured both by self-assessment and by the assessment of independent observers.

Selective attention and response competition in schizophrenic patients.

Visual distractibility was studied in schizophrenic patients. Subjects had to respond to target stimuli while they ignored the visual context, which was either congruent, neutral, or incongruent with respect to the target stimulus. Eighteen schizophrenic patients and 18 healthy subjects performed this flanker task. Schizophrenic patients did not show increased distractibility compared with healthy subjects, and both groups showed the same attenuation of visual context effects when the spatial distance between target and flanker stimuli was increased. The two groups showed the same amount of interference by incongruent visual context. Thus, schizophrenic patients did not show enhanced distractibility, spatial extension of attention, or response competition. When flanker and target stimuli were redundant, the responses of schizophrenic patients were less accelerated than those of healthy subjects.

Loudness judgments, evoked potentials, and reaction time to acoustic stimuli early and late in the cardiac cycle in chronic schizophrenics.

Two experiments were performed to test Broen's (1968) theory that chronic schizophrenics show increased sensitivity of the inhibitory mechanisms assumed to follow cardiovascular baroreceptor stimulation. Subjects were chronic schizophrenics and normals matched for age and education. In Experiment I reaction times, vertex potentials, and loudness judgments to single tones presented during systole or diastole were analyzed. Contrary to expectation, schizophrenics more often judged tones presented during systole to be louder than tones presented during diastole; the opposite was true for normals. A similar pattern was found in Experiment II, where pairs of tones were presented instead of single tones. No influence of cardiac cycle on reacion time or evoked potentials emerged. Results do not support Broen's assumption.

Self assessment of relapse risk and assertiveness in relation to treatment outcome of female alcoholics.

Prior to and following social-skills training during a three months inpatient treatment, 145 female alcoholics indicated for various situations involving social pressure to drink alcohol (a) how difficult it would be for them not to drink (Relapse Risk) and (b) the degree of discomfort they expected (Specific Assertiveness). In addition, General Assertiveness situations, not related to alcohol, were evaluated. Patients who relapsed three months after treatment evaluated the situations more difficult to deal with and creating more discomfort than abstaining patients, although the groups did not differ in their self-rated assertiveness in non-alcohol-related situations. All ratings improved throughout the training, but the differences between outcome groups were similar before and after. When patients were excluded who had relapsed already during treatment, Relapse Risk but not Specific Assertiveness still discriminated between outcome groups. The prognostic power of the Risk rating seems to reflect a general efficacy expectation evident in a strong relation to patients' conviction of being able to stay abstinent, stated already at admission.

Placebo injections and surveillance of alcohol intake during inpatient treatment of female alcoholics.

Institutions for treating alcoholics differ widely with respect to how restrictively they apply psychopharmacological agents and how rigorously they control patients for intake of alcohol. This study investigates the impact of such policies on relapse rates. During a three month inpatient treatment, 70 female alcoholics were assigned to one of four conditions: (a) strict surveillance of alcohol intake by means of breath tests and frequent checks of patient's rooms as well as injections of a placebo purportedly reducing craving, (b) no surveillance but placebo injections, (c) surveillance but no placebo injections, and (d) neither surveillance nor placebo injections. The amount of surveillance did not influence relapse rates. However, during inpatient treatment more relapses occurred among patients who received the placebo injections than among those who did not. Although this effect was no longer significant following treatment, the increase of relapse rates suggests caution in the application of nonspecific medication in the treatment of alcoholics.

Implicit memory in schizotypal subjects and normal controls: effects of a secondary task on sequence learning.

Using a serial reaction-time task, the implicit memory performances of 29 high scoring (schizotypes) and 24 low scoring subjects (controls) on the German version of the 1997 Schizotypal Personality Questionnaire by Klein, Andresen, and Jahn were compared. To test the hypothesis that schizotypes show a differential deficit, subjects participated either in a single task condition of the serial reaction-time task or in a dual task condition of a secondary tone-counting task. Neither under single task conditions nor under dual task conditions did schizotypes show any impairment of implicit memory compared with controls. In addition, a separate analysis of the response latencies for the unique and ambiguous transitions of the repeated sequence did not indicate any differences between the two groups. These findings support and augment the results reported by Ferraro and Okerlund (1995).

[Ill due to amalgam? 10 rules for managing the symptomatic patient]. / Krank durch Amalgam? Zehn Regeln für den Umgang mit Betroffenen.

Over the past two decades, mercury released by amalgam fillings has been held responsible for a number of mental and somatic health complaints. However, a systematic relation between increased mercury levels and the severity of the reported symptoms has never been demonstrated in any of the present well-controlled multidisciplinary studies. These studies, however, have found a high prevalence of mental disorders, especially somatization syndromes, among patients with self-diagnosed "amalgam illness". Additionally, our own studies indicate that amalgam anxiety is often merely one aspect of a general environmental anxiety. Overall, the present findings suggest a psychological etiology for amalgam-related complaints. Our psychosomatic model of "amalgam illness" integrates external factors, individual predispositions and specific processes of perception, awareness, evaluation and attribution. Practical management strategies for primary care physicians can be derived from this model.

Electrophysiological indices of error monitoring in juvenile and adult attention deficit hyperactivity disorder (ADHD)--a meta-analytic appraisal.

Attempts to identify the central disturbed processes explaining the overt symptoms of juvenile and adult ADHD rely heavily on the concept of deficient error monitoring processes. A number of studies have investigated event-related potentials (ERPs) and behavioral performance in tasks traditionally used to probe the interference control and inhibition of motor responses. The inspection of the error negativity (Ne/ERN) and error positivity (Pe) components evoked in these tasks has produced conflicting results with respect to the nature and extent of an error monitoring deficit in ADHD. A meta-analytic aggregation of these single studies should help develop a reliable appraisal of the evidence for the compromised performance monitoring processes in ADHD. Our meta-analysis was confined to studies of adult and juvenile ADHD participants examined in GoNogo and Flanker task studies that also reported the Ne/ERN and Pe ERP components. Only seven studies were suited for the meta-analysis, but their aggregation nevertheless led to clear results: Ne was attenuated in adult and adolescent ADHD participants for both tasks, and Pe was attenuated only in the GoNogo tasks. The ADHD participants made more errors than the controls in both tasks but responded slower only in the Flanker task. To our knowledge, this meta-analysis is the first to compare electrophysiological and behavioral indices of error monitoring in adult and juvenile ADHD patients and healthy controls. Admittedly, the data available for this comparison were sparse and heterogeneous; nevertheless, this meta-analysis produced salient results that indicate a monitoring deficit as a central feature of the ADHD syndrome.