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Selected AbstractsEffects of suppressing negative memories on intrusions and autobiographical memory specificityAPPLIED COGNITIVE PSYCHOLOGY, Issue 3 2010Elke Geraerts This study examines whether avoidance of negative memories results in intrusions as well as reduced memory specificity. Healthy participants suppressed memories of either a negative or a neutral autobiographical event. Individuals who suppressed negative memories tended to demonstrate smaller increases in negative mood than those who did not suppress their negative target memory. Neither suppression nor valence of the to-be-suppressed memory predicted decreases in memory specificity. Target memory-related intrusions during autobiographical memory retrieval predicted larger reductions in specific memory recall. Our findings are discussed in terms of affect regulation and other accounts of over-general memory. Copyright © 2010 John Wiley & Sons, Ltd. [source] Effects of preoccupation on interpersonal recall: a pilot studyDEPRESSION AND ANXIETY, Issue 1 2009Annukka Lehtonen Ph.D. Abstract Background: The aim of this pilot study was to examine whether priming preoccupation (rumination) in healthy participants adversely affects the processing of interpersonal information. Methods: Sixty female undergraduates with moderate or marked preoccupation proneness (selected on the basis of their high preoccupation on eating, shape, and weight issues) were randomized to receive either a general preoccupation prime, a standardized preoccupation prime, or a control prime. Following the prime, participants watched an 8-min videotape of a family interaction and then were asked free recall questions about the tape. Results: Participants who received the general preoccupation prime scored lower than the other two groups in response to free recall questions regarding emotion-related topics. Conclusions: These findings suggest that when primed by everyday worries and concerns, individuals prone to preoccupation may have their capacity to recall emotion-related interpersonal information compromised. Depression and Anxiety, 2009. © 2008 Wiley-Liss, Inc. [source] Investigation of mood-congruent false and true memory recognition in depressionDEPRESSION AND ANXIETY, Issue 1 2005Steffen Moritz Ph.D. Abstract The present study investigated the extent of mood-congruent false and true memory recognition in depression. A group of 25 patients with depression and 28 healthy controls completed a variant of the Deese-Roediger McDermott task. Four lists were read to participants in sequence, followed by a recognition task. The words in each list were associated with a central but unmentioned theme word that was either depression-relevant (i.e., loneliness), delusion-relevant (betrayal), positive (holidays), or neutral (window). Whereas it was expected to replicate the conventional mood-congruent effect in depression (better recognition of depression-relevant items), the available literature did not allow strong predictions to be made on the extent of mood-congruent false recognition in depression. Results showed that depressed patients learned emotionally charged material equally well as healthy participants but forgot significantly more neutral material. A conventional mood-congruent memory bias was not found, but relative to healthy controls, patients with depression committed more false recognition errors for emotionally charged words, particularly for depression-relevant items. The results confirm that depressed patients are biased toward emotional material. Reasons for the absence of the expected mood-congruent memory bias are discussed. It is suggested that researchers as well as clinicians should pay more attention to mood-congruent false recollection, because it may undermine the validity of autobiographic reports in depressive patients and may represent a maintenance factor for the disorder. Depression and Anxiety 00:000,000, 2005. © 2005 Wiley-Liss, Inc. [source] Working memory and multi-tasking in paranoid schizophrenia with and without comorbid substance use disorderADDICTION, Issue 5 2008Patrizia Thoma ABSTRACT Aims Addiction is a frequent comorbid disorder in schizophrenia and associated with poor outcome. The present study sought to determine whether addicted and non-addicted schizophrenic patients are impaired differentially on the executive abilities of working memory and multi-tasking which are relevant for maintaining abstinence. Design Comparisons of executive performance in clinical and control groups. Setting In-patient setting. Participants The cognitive profile of schizophrenic patients with and without comorbid substance abuse disorder was compared with that of patients suffering from major depression or alcoholism and healthy participants. Measurements A range of cognitive tasks was used to assess: (i) the ability to update continuously context information in working memory and to use it for action selection; and (ii) the capacity to divide attention between different sensory input channels and to coordinate verbal and manual responses. Findings Single-diagnosis schizophrenic patients showed pronounced impairments on measures of online maintenance and use of context information. Their ability to coordinate different sensory input channels (divided attention) was also impaired. Addicted schizophrenics showed evidence of impaired sensory input management and of reduced context sensitivity, when age differences were controlled. Conclusions The present study indicates severe working memory and multi-tasking deficits in schizophrenia which are, however, not exacerbated by comorbid addiction. [source] In-group reassurance in a pain setting produces lower levels of physiological arousal: direct support for a self-categorization analysis of social influence,EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 4 2007Michael J. Platow A large body of research demonstrates a strong social component to people's pain experiences and pain-related behaviours. We investigate this by examining the impact of social-influence processes on laboratory-induced pain responses by manipulating the social-categorical relationship between the person experiencing pain and another who offers reassurance. We show that physiological arousal associated with laboratory-induced pain is significantly lower in normal, healthy participants following reassurance about the pain-inducing activity when that reassurance comes from an in-group member in contrast to reassurance from an out-group member and a no reassurance control. These data are consistent with predictions derived from self-categorization theory, providing convincing empirical support of its analysis of social influence using a non-reactive measure. These data also represent a clear advance within the pain literature by identifying a possible common process to the social-psychological component of pain responses. Copyright © 2006 John Wiley & Sons, Ltd. [source] Effect of unitization on associative recognition in amnesiaHIPPOCAMPUS, Issue 3 2007Joel R. Quamme Abstract We examined how associative recognition performance in amnesic patients is mediated by use of a unitized (i.e., holistic) encoding strategy, and the degree to which the unitization effect is related to sparing of familiarity-based recognition. Participants studied word pairs as either separate lexical units in sentences (i.e., nonunitized) or as compounds (unitized). Under standard recognition instructions, normal controls and patients with left-temporal lobe damage (previously determined to have impairments in both recollection and familiarity) showed no difference for unitized and nonunitized pairs, whereas hypoxics (previously determined to have impaired recollection but relatively preserved familiarity) showed an advantage of unitized over nonunitized pairs. This effect was reproduced in normal healthy participants under instructions to restrict responses to judgments of familiarity. The results indicate that unitization may mediate the degree of associative recognition impairment exhibited by some amnesic patients, and that the effect is related to preserved familiarity capacity. The relevance of the results to the debate over the importance of the hippocampus in memory for associations is discussed. © 2007 Wiley-Liss, Inc. [source] Changes in the interaction of resting-state neural networks from adolescence to adulthoodHUMAN BRAIN MAPPING, Issue 8 2009Michael C. Stevens Abstract This study examined how the mutual interactions of functionally integrated neural networks during resting-state fMRI differed between adolescence and adulthood. Independent component analysis (ICA) was used to identify functionally connected neural networks in 100 healthy participants aged 12,30 years. Hemodynamic timecourses that represented integrated neural network activity were analyzed with tools that quantified system "causal density" estimates, which indexed the proportion of significant Granger causality relationships among system nodes. Mutual influences among networks decreased with age, likely reflecting stronger within-network connectivity and more efficient between-network influences with greater development. Supplemental tests showed that this normative age-related reduction in causal density was accompanied by fewer significant connections to and from each network, regional increases in the strength of functional integration within networks, and age-related reductions in the strength of numerous specific system interactions. The latter included paths between lateral prefrontal-parietal circuits and "default mode" networks. These results contribute to an emerging understanding that activity in widely distributed networks thought to underlie complex cognition influences activity in other networks. Hum Brain Mapp 2009. © 2009 Wiley-Liss, Inc. [source] Brain network dynamics during error commissionHUMAN BRAIN MAPPING, Issue 1 2009Michael C. Stevens Abstract Previous studies suggest that the anterior cingulate and other prefrontal brain regions might form a functionally-integrated error detection network in the human brain. This study examined whole brain functional connectivity to both correct and incorrect button presses using independent component analysis (ICA) of functional magnetic resonance imaging (fMRI) data collected from 25 adolescent and 25 adult healthy participants (ages 11,37) performing a visual Go/No-Go task. Correct responses engaged a network comprising left lateral prefrontal cortex, left postcentral gyrus/inferior parietal lobule, striatum, and left cerebellum. In contrast, a similar network was uniquely engaged during errors, but this network was not integrated with activity in regions believed to be engaged for higher-order cognitive control over behavior. A medial/dorsolateral prefrontal-parietal neural network responded to all No-Go stimuli, but with significantly greater activity to errors. ICA analyses also identified a third error-related circuit comprised of anterior temporal lobe, limbic, and pregenual cingulate cortices, possibly representing an affective response to errors. There were developmental differences in error-processing activity within many of these neural circuits, typically reflecting greater hemodynamic activation in adults. These findings characterize the spatial structure of neural networks underlying error commission and identify neurobiological differences between adolescents and adults. Hum Brain Mapp 2009. © 2007 Wiley-Liss, Inc. [source] Cognitive function, P3a/P3b brain potentials, and cortical thickness in agingHUMAN BRAIN MAPPING, Issue 11 2007Anders M. Fjell Abstract The purpose of the study was to assess the relationship between the P3a/P3b brain potentials, cortical thickness, and cognitive function in aging. Thirty-five younger and 37 older healthy participants completed a visual three-stimuli oddball ERP (event-related potential)-paradigm, a battery of neuropsychological tests, and MRI scans. Groups with short vs. long latency, and low vs. high amplitude, were compared on a point by point basis across the entire cortical mantle. In the young, thickness was only weakly related to P3. In the elderly, P3a amplitude effects were found in parietal areas, the temporoparietal junction, and parts of the posterior cingulate cortex. P3b latency was especially related to cortical thickness in large frontal regions. Path models with the whole sample pooled together were constructed, demonstrating that cortical thickness in the temporoparietal cortex predicted P3a amplitude, which in turn predicted executive function, and that thickness in orbitofrontal cortex predicted P3b latency, which in turn predicted fluid function. When age was included in the model, the relationship between P3 and cognitive function vanished, while the relationship between regional cortical thickness and P3 remained. It is concluded that thickness in specific cortical areas correlates with scalp recorded P3a/P3b in elderly, and that these relationships differentially mediate higher cognitive function. Hum Brain Mapp 2007. © 2007 Wiley-Liss, Inc. [source] fMRI analysis for motor paradigms using EMG-based designs: A validation studyHUMAN BRAIN MAPPING, Issue 11 2007Anne-Fleur van Rootselaar Abstract The goal of the present validation study is to show that continuous surface EMG recorded simultaneously with 3T fMRI can be used to identify local brain activity related to (1) motor tasks, and to (2) muscle activity independently of a specific motor task, i.e. spontaneous (abnormal) movements. Five healthy participants performed a motor task, consisting of posture (low EMG power), and slow (medium EMG power) and fast (high EMG power) wrist flexion,extension movements. Brain activation maps derived from a conventional block design analysis (block-only design) were compared with brain activation maps derived using EMG-based regressors: (1) using the continuous EMG power as a single regressor of interest (EMG-only design) to relate motor performance and brain activity, and (2) using EMG power variability as an additional regressor in the fMRI block design analysis to relate movement variability and brain activity (mathematically) independent of the motor task. The agreement between the identified brain areas for the block-only design and the EMG-only design was excellent for all participants. Additionally, we showed that EMG power variability correlated well with activity in brain areas known to be involved in movement modulation. These innovative EMG-fMRI analysis techniques will allow the application of novel motor paradigms. This is an important step forward in the study of both the normally functioning motor system and the pathophysiological mechanisms in movement disorders. Hum Brain Mapp, 2007. © 2007 Wiley-Liss, Inc. [source] Improving functional magnetic resonance imaging motor studies through simultaneous electromyography recordingsHUMAN BRAIN MAPPING, Issue 9 2007Bradley J. MacIntosh Abstract Specially designed optoelectronic and data postprocessing methods are described that permit electromyography (EMG) of muscle activity simultaneous with functional MRI (fMRI). Hardware characterization and validation included simultaneous EMG and event-related fMRI in 17 healthy participants during either ankle (n = 12), index finger (n = 3), or wrist (n = 2) contractions cued by visual stimuli. Principal component analysis (PCA) and independent component analysis (ICA) were evaluated for their ability to remove residual fMRI gradient-induced signal contamination in EMG data. Contractions of ankle tibialis anterior and index finger abductor were clearly distinguishable, although observing contractions from the wrist flexors proved more challenging. To demonstrate the potential utility of simultaneous EMG and fMRI, data from the ankle experiments were analyzed using two approaches: 1) assuming contractions coincided precisely with visual cues, and 2) using EMG to time the onset and offset of muscle contraction precisely for each participant. Both methods produced complementary activation maps, although the EMG-guided approach recovered more active brain voxels and revealed activity better in the basal ganglia and cerebellum. Furthermore, numerical simulations confirmed that precise knowledge of behavioral responses, such as those provided by EMG, are much more important for event-related experimental designs compared to block designs. This simultaneous EMG and fMRI methodology has important applications where the amplitude or timing of motor output is impaired, such as after stroke. Hum Brain Mapp 2006. © 2006 Wiley-Liss, Inc. [source] Diazepam-induced prospective memory impairment and its relation to retrospective memory, attention, and arousalHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 2 2006Jill B. Rich Abstract The amnestic effects of benzodiazepines are well documented on a variety of memory tasks. However, prospective memory (PM), or remembering to execute an action at a future time, has not been studied previously. This study examined the effect of diazepam on word list recall, PM, sustained attention, and subjective ratings of arousal. Forty-eight healthy participants, aged 19,35, received an average of 0.19,mg/kg oral diazepam or placebo in a double-blind manner. Retrospective memory and PM were assessed by free recall of unrelated word lists and by instructing participants to request a hidden belonging at the end of the session, respectively. Sustained attention was measured by multiple trials of a digit cancellation task, and subjective arousal was assessed by self-ratings of drowsiness. Diazepam impaired performance on all measures, including PM. Reduced PM performance was associated with decreased subjective arousal in the diazepam group but was unrelated to sustained attention. This is the first report of the effects of benzodiazepines on prospective remembering, and further supports the view that the arousal/attentional system is composed of partially independent subsystems that have differential relationships to memory. Copyright © 2005 John Wiley & Sons, Ltd. [source] Prevalence and longitudinal stability of negative symptoms in healthy participantsINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 12 2009Lindsay C. Emmerson Abstract Objective Although negative symptoms are prominent in older patients with schizophrenia, it is unknown whether this pattern is prevalent in healthy participants. The objective of this study was to evaluate whether negative symptoms are present in healthy populations and to determine whether they are linked to illness-related processes or normal aging. Methods A systemic review of 26 studies that have administered negative symptom assessments to healthy participants was conducted. In addition, 213 (age,>,40,years old) healthy participants completed PANSS and SANS ratings at both baseline and 1-year follow-up. One-hundred participants also completed ratings after 3 years. Results Across all reviewed studies, negative symptoms were absent in the majority of participants. Comparable results were found in the current study's large longitudinal evaluation with middle-aged to older adults. Conclusions Taken together, the data suggest that healthy volunteers do not suffer from prominent negative symptoms. This finding is consistent with the hypothesis that the greater prevalence and severity of negative symptoms in older patients is not related to normal aging but to illness-related processes. Copyright © 2009 John Wiley & Sons, Ltd. [source] The Ankylosing Spondylitis Quality of Life Questionnaire: validation in a New Zealand cohortINTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 4 2010Katherine JENKS Abstract Aim:, To examine the validity of the Ankylosing Spondylitis Quality of Life Questionnaire (ASQoL) in a New Zealand population with defined axial spondyloarthritis (SpA). Once validated, the ASQoL will be included as an outcome measure in a proposed multicentre New Zealand study. Methods:, Five healthy participants were interviewed to identify any issues related to local dialect or linguistic comprehension of the questionnaire. Cognitive debriefing interviews were conducted with four participants with SpA to assess the relevance and comprehensiveness of the questionnaire. Internal consistency was established by determining the Cronbach's alpha. Finally, convergent validity of the ASQoL was assessed by testing the correlation with the Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and patient global visual analogue scale (VAS) scores in a cohort of 63 SpA patients. Results:, The language used in the ASQoL was considered clear, comprehensible and accessible to speakers of New Zealand English. The questionnaire displayed content validity for patients with SpA. The ASQoL had good internal consistency in the present sample (, = 0.854). A positive correlation was found between the ASQoL and the BASFI (rho = 0.635, P < 0.001), BASDAI (rho = 0.521, P < 0.001) and patient global assessment VAS (rho = 0.546, P < 0.001), providing evidence that the ASQoL has convergent validity among patients with SpA in New Zealand. Test,retest reliability was good over 16 weeks (rho = 0.730, P < 0.001). Conclusions:, The ASQoL has been demonstrated in this study to be feasible, internally consistent and to have content and convergent validity in a New Zealand population of patients with axial spondyloarthritis; it is a measure of quality of life which is both easy to employ and reliable. [source] Psychological Stress and Oxidative Damage in Lymphocytes of Aerobically Fit and Unfit Individuals,JOURNAL OF APPLIED BIOBEHAVIORAL RESEARCH, Issue 1 2008Kelly Z. Knickelbein Habitual aerobic exercise has a beneficial effect on many systems of the body, and psychological stress has a negative influence on several of the same systems. One possible pathway is through those systems that account for the detrimental effects of stress; by buffering these harmful effects, exercise may reduce the consequences of stress. This study examined increased resistance of cells to stress-induced oxidative damage as a result of fitness. Forty healthy participants were assigned to either a stress group or a no-stress control group, and measures of stress and oxidative damage were collected. Variation in fitness level across participants was also measured. Oxidative damage increased as a function of stress, but this was not buffered by fitness level. These results should be interpreted with caution because of the small sample size and the limited variability of cardiorespiratory fitness levels in the sample. [source] Impaired decision making following 49 h of sleep deprivationJOURNAL OF SLEEP RESEARCH, Issue 1 2006WILLIAM D. S. KILLGORE Summary Sleep deprivation reduces regional cerebral metabolism within the prefrontal cortex, the brain region most responsible for higher-order cognitive processes, including judgment and decision making. Accordingly, we hypothesized that two nights of sleep loss would impair decision making quality and lead to increased risk-taking behavior on the Iowa Gambling Task (IGT), which mimics real-world decision making under conditions of uncertainty. Thirty-four healthy participants completed the IGT at rested baseline and again following 49.5 h of sleep deprivation. At baseline, volunteers performed in a manner similar to that seen in most samples of healthy normal individuals, rapidly learning to avoid high-risk decks and selecting more frequently from advantageous low-risk decks as the game progressed. After sleep loss, however, volunteers showed a strikingly different pattern of performance. Relative to rested baseline, sleep-deprived individuals tended to choose more frequently from risky decks as the game progressed, a pattern similar to, though less severe than, previously published reports of patients with lesions to the ventromedial prefrontal cortex. Although risky decision making was not related to participant age when tested at rested baseline, age was negatively correlated with advantageous decision making on the IGT, when tested following sleep deprivation (i.e. older subjects made more risky choices). These findings suggest that cognitive functions known to be mediated by the ventromedial prefrontal cortex, including decision making under conditions of uncertainty, may be particularly vulnerable to sleep loss and that this vulnerability may become more pronounced with increased age. [source] Effects of bisacodyl on ascending colon emptying and overall colonic transit in healthy volunteersALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2009N. MANABE Summary Background, The mechanism of action of bisacodyl in the unprepared human colon remains unclear. Aim, To evaluate the effect of oral bisacodyl on the overall and regional colonic transit in humans. Methods, In a double-blind, randomized, placebo-controlled study of 25 healthy participants, effects of oral bisacodyl (5 mg p.o. per day) and placebo on colonic transit were compared. A validated scintigraphy method was used to measure colonic transit. The primary transit endpoints, ascending colon emptying t1/2 and geometric centre of colon isotope at 24 h (overall transit), were compared (Wilcoxon rank sum test). Results, There were significant treatment effects on ascending colon t1/2, with the bisacodyl group demonstrating accelerated emptying [median 6.5 h, interquartile range 5.0,8.0 h] relative to the placebo group [11.0 h (7.0,17.1); P = 0.03]. Numerical differences in colonic geometric centre 24 h [bisacodyl median 3.0 (2.2,3.8), placebo 4.0 (3.1,4.6)] were not significant (P = 0.19). There were no significant differences observed in geometric centre 4 h. Conclusion, Oral 5 mg bisacodyl accelerates ascending colon in the unprepared colon in healthy adults; this action may contribute to the drug's efficacy in constipation. [source] Beneficial effect of transcranial magnetic stimulation on sleep in Parkinson's disease,MOVEMENT DISORDERS, Issue 6 2009Karin D. van Dijk MD Abstract Sleep disorders are common in Parkinson's disease (PD) and have profound negative influences on quality of life. Sleep structure in healthy participants can be changed by repetitive transcranial magnetic stimulation (rTMS), but this has never been studied systematically in PD. Therefore, we characterized sleep in PD patients and examined effects of rTMS using a combination of actigraphy and a pressure sensitive pad. Thirteen PD patients received 5 Hz rTMS over the motor or parietal cortex. Actigraphic sleep estimates were obtained before, during and after rTMS, as well as compared with 8 healthy, age-matched controls. Motor symptoms and mood were evaluated before and after rTMS. Mixed-model regression analyses indicated that PD patients slept shorter (350 ± 17 vs. 419 ± 24 min., P = 0.02), more fragmented (fragmentation index 41 ± 4 vs. 22 ± 2, P = 0.0004) and had a lower sleep efficiency (77 ± 2 vs. 86 ± 2%, P = 0.002) and longer nocturnal awakenings (3.4 ± 0.2 vs. 2.3 ± 0.2 min., P = 0.003) than healthy controls. rTMS over the parietal, but not over the motor cortex improved sleep fragmentation (P = 0.0002) and sleep efficiency (P = 0.0002) and reduced the average duration of nocturnal awakenings (P = 0.02). No change of motor symptoms or mood was observed. Disturbed sleep in PD patients may partly be reversed by parietal rTMS, without affecting motor symptoms or mood. © 2009 Movement Disorder Society [source] 35 Electrogastrography in healthy participants: comparison of children and adultsNEUROGASTROENTEROLOGY & MOTILITY, Issue 6 2006CA FRIESEN The current study examined whether electrogastrogram (EGG) patterns differ between children/adolescents and adults, including whether EGG recordings obtained from healthy children would be considered normal by standards established for adults. Twenty-eight healthy children (54% females; ages 8,17, M = 12.4 years) were evaluated and compared to 15 healthy adults. EGGs were recorded for 30 min in the fasting state and for 1 h following a standard meal. For both pediatric and adult participants, there was a significant increase in both the dominant frequency and the dominant power from the pre- to the post , prandial period (p < 0.001 for each). There was a significant post-prandial increase in the %normal slow waves in pediatric participants only (81.5 vs. 89.0% vs. p < 0.001). Children demonstrated a significantly lower mean fasting %normal slow waves (81.5% vs. 94.2%) and a significantly greater fasting % tachygastria (8.9% vs. 2.3%) than did adults. Other parameters did not differ. Using adult standards, the %normal slow waves were ,70% of recording time in 96% children in the fasting state and in 100% in the postprandial period. A postprandial power increase was seen in 89% of the children. In conclusion, while adults should not be used as controls in pediatric studies of EGG, our data would indicate that American Motility Society (AMS) consensus adult criteria for a normal EGG are appropriate to apply to children and adolescents when utilizing methodology and meal challenge similar to that used to establish the adult norms. [source] Normative data on Benton Visual Form Discrimination Test for older adults and impaired scores in Clinical Dementia Rating 0.5 participants: Community-based study.PSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 1 2009Tajiri Project, The Osaki Aims:, The Benton Visual Form Discrimination test (VFD) is one of the non-verbal tests to assess the capacity for complex visual form discrimination. The purposes of the present study were to investigate the effects of age and education level of the VFD in healthy elderly subjects, rigorously excluding participants with Clinical Dementia Rating (CDR) 0.5, and the characteristics of VFD patterns in CDR 0.5 participants. Methods:, The 597 participants included CDR 0 (healthy elderly, n = 405), CDR 0.5 (mild cognitive impairment, n = 161), and CDR 1 and 2 (dementia, n = 31). The VFD, Digit Forwards, Digit Backwards and Rey,Osterrieth Complex Figure Test (RCFT) copying were used for neuropsychological assessment. Results:, There were significant effects of age and education level on the VFD in healthy participants, and the CDR 0.5 group had a lower score on the VFD than the healthy group. Low performance on the VFD was associated with Digit Backward and RCFT copying in both healthy and CDR 0.5 participants. Conclusions:, CDR 0.5 participants exhibit deficits of visual form discrimination related to attention, visual construction and organization. [source] Empathy and error processingPSYCHOPHYSIOLOGY, Issue 3 2010Michael J. Larson Abstract Recent research suggests a relationship between empathy and error processing. Error processing is an evaluative control function that can be measured using post-error response time slowing and the error-related negativity (ERN) and post-error positivity (Pe) components of the event-related potential (ERP). Thirty healthy participants completed two measures of empathy, the Interpersonal Reactivity Index (IRI) and the Empathy Quotient (EQ), and a modified Stroop task. Post-error slowing was associated with increased empathic personal distress on the IRI. ERN amplitude was related to overall empathy score on the EQ and the fantasy subscale of the IRI. The Pe and measures of empathy were not related. Results remained consistent when negative affect was controlled via partial correlation, with an additional relationship between ERN amplitude and empathic concern on the IRI. Findings support a connection between empathy and error processing mechanisms. [source] The effects of paced breathing on respiratory resistance are minimal in healthy individualsPSYCHOPHYSIOLOGY, Issue 5 2009Thomas Ritz Abstract Paced breathing has been criticized for its presumed influences on autonomic and respiratory regulation, among that on respiratory resistance. It has been speculated that excessive pulmonary stretch receptor activation through high tidal volume (VT) would be the mechanism underlying such influences. However, the idea of airway dilation by paced breathing has remained untested. We analyzed inspiratory and expiratory resistance measured by forced oscillations in 26 healthy participants during baseline and two paced breathing conditions, regular pacing with instructions to alter rate only and pacing with additional instructions to alter volume randomly throughout the task. In each condition, four 3-min paced breathing trials at 8, 10.5, 13, and 18 breaths/min were administered. Despite pronounced changes in respiration rates and VT across pacing trials, neither inspiratory nor expiratory resistance were changed significantly under the regular paced breathing condition. A small reduction in resistance was only observed under conditions of variable volume at 18 breaths/min. Thus, regular paced breathing at different speeds across a range of naturally occurring breathing frequencies has only minimal effects on resistance of the airway passages. [source] The electrophysiological correlates sustaining the retrieval of face,name associations: An ERP studyPSYCHOPHYSIOLOGY, Issue 4 2004F. Joassin Abstract An ERP study on 9 healthy participants was carried out to temporally constrain the neural network proposed by Campanella et al. (2001) in a PET study investigating the cerebral areas involved in the retrieval of face,name associations. Three learning sessions served to familiarize the participants with 24 face,name associations grouped in 12 male/female couples. During EEG recording, participants were confronted with four experimental conditions, requiring the retrieval of previously learned couples on the basis of the presentation of name,name (NN), face,face (FF), name,face (NF), or face,name (FN) pairs of stimuli. The main analysis of this experiment consisted in the subtraction of the nonmixed conditions (NN and FF) from the mixed conditions (NF and FN). It revealed two main ERP components: a negative wave peaking at left parieto-occipital sites around 285 ms and its positive counterpart recorded at left centro-frontal electrodes around 300 ms. Moreover, a dipole modeling using three dipoles whose localization corresponded to the three cerebral areas observed in the PET study (left inferior frontal gyrus, left medial frontal gyrus, left inferior parietal lobe) explained more than 90% of the variance of the results. The complementarity between anatomical and neurophysiological techniques allowed us to discuss the temporal course of these cerebral activities and to propose an interactive and original anatomo-temporal model of the retrieval of face,name associations. [source] Electrophysiological insights into language processing in schizophreniaPSYCHOPHYSIOLOGY, Issue 6 2002Tatiana Sitnikova Deficits in language comprehension in schizophrenia were examined using event-related potentials (ERPs). Schizophrenic and healthy participants read sentences in which the first clause ended with a homograph, and the second clause started with a target word that was semantically related to the homograph's dominant meaning (e.g., 1. Diving was forbidden from the bridge because the river had rocks in it. or 2. The guests played bridge because the river had rocks in it.). Processing of the targets (e.g., "river") was expected to be primarily influenced by the preceding overall sentence context (congruent in 1; incongruent in 2) in healthy participants, but to be inappropriately affected by the dominant meaning of homographs (e.g., the "structure" meaning of "bridge") in sentences like 2 in schizophrenic patients. The N400 ERP component that is known to be sensitive to contextual effects during language processing confirmed these predictions. This showed that language abnormalities in schizophrenia may be related to deficient processing of context-irrelevant semantic representations of words from the discourse. [source] Comparison between the Fourier and Wavelet methods of spectral analysis applied to stationary and nonstationary heart period dataPSYCHOPHYSIOLOGY, Issue 5 2001Jan H. Houtveen The aim of this study was to assess the error made by violating the assumption of stationarity when using Fourier analysis for spectral decomposition of heart period power. A comparison was made between using Fourier and Wavelet analysis (the latter being a relatively new method without the assumption of stationarity). Both methods were compared separately for stationary and nonstationary segments. An ambulatory device was used to measure the heart period data of 40 young and healthy participants during a psychological stress task and during periods of rest. Surprisingly small differences (<1%) were found between the results of both methods, with differences being slightly larger for the nonstationary segments. It is concluded that both methods perform almost identically for computation of heart period power values. Thus, the Wavelet method is only superior for analyzing heart period data when additional analyses in the time-frequency domain are required. [source] Cortical folding difference between patients with early-onset and patients with intermediate-onset bipolar disorderBIPOLAR DISORDERS, Issue 4 2009Jani Penttilä Objectives:, Cerebral abnormalities have been detected in patients with bipolar disorder (BD). In comparison to BD with a later onset, early-onset BD has been found to have a poorer outcome. However, it is yet unknown whether neuroanatomical abnormalities differ between age-at-onset subgroups of the illness. We searched for cortical folding differences between early-onset (before 25 years) and intermediate-onset (between 25 and 45 years) BD patients. Methods:, Magnetic resonance images of 22 early-onset BD patients, 14 intermediate-onset BD patients, and 50 healthy participants were analyzed using a fully automated method to extract, label, and measure the sulcal area in the whole cortex. Cortical folding was assessed by computing global sulcal indices (the ratio between total sulcal area and total outer cortex area) for each hemisphere, and local sulcal indices for 12 predefined regions in both hemispheres. Results:, Intermediate-onset BD patients had a significantly reduced local sulcal index in the right dorsolateral prefrontal cortex in comparison to both early-onset BD patients and healthy subjects, and lower global sulcal indices in both hemispheres in comparison to healthy subjects (p < 0.05, Bonferroni corrected). Brain tissue volumes did not differ between groups. Conclusions:, This study provided the first evidence of a neuroanatomic difference between intermediate-onset and early-onset BD, which lends further support to the existence of different age-at-onset subgroups of BD. [source] Preliminary evidence for persistent abnormalities in amygdala volumes in adolescents and young adults with bipolar disorderBIPOLAR DISORDERS, Issue 6 2005Hilary P Blumberg Objectives:, Abnormalities in volumes of the amygdala have been reported previously in adolescents and adults with bipolar disorder (BD). Several studies have reported reduced volumes in adolescents with BD; however, both decreases and increases in volumes have been reported in adults with BD. Understanding of potential developmental contributions to these disturbances in morphology of the amygdala has been limited by the absence of longitudinal data in persons with BD. Here we use a within-subject longitudinal design to investigate whether amygdala volume abnormalities persist in adolescents and young adults with BD over a time interval of approximately 2 years. Methods:, Participants included 18 adolescents and young adults: 10 participants with BD I and 8 healthy comparison participants. Amygdala volumes were measured on high-resolution magnetic resonance imaging scans acquired twice for each subject over intervals of approximately 2 years. Amygdala volumes were the dependent measures in a mixed-model statistical analysis to compare amygdala volumes between groups over time while covarying for total brain volume. Results:, Amygdala volumes were significantly smaller in adolescents and young adults with BD compared with healthy participants (p = 0.018). The effect of time was not significant. Conclusions:, Although the sample size is modest, this study provides preliminary evidence to support the presence of decreased amygdala volumes in adolescents and young adults with BD that persist during this developmental epoch. [source] Apraxia related with subcortical lesions due to cerebrovascular diseaseACTA NEUROLOGICA SCANDINAVICA, Issue 1 2010N. E. Tabaki Tabaki NE, Vikelis M, Besmertis L, Vemmos K, Stathis P, Mitsikostas DD. Apraxia related with subcortical lesions due to cerebrovascular disease. Acta Neurol Scand: 2010: 122: 9,14. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objectives,,, To examine whether ideomotor apraxia exists in patients with subcortical ischemic lesions. Patients and Methods,,, A matched-control, prospective and multi-centered research design was used. Ideomotor apraxia, anxiety and depression were assessed by the Movement Imitation Test and the Hamilton scales, respectively. Results,,, Forty two consecutive patients with subcortical ischemic stroke and an equal number of healthy participants, matched in age and sex were included. Paired-sample t-tests showed that patients had significantly more apractic elements in their movements (t = 5.03, P < 0.01), higher anxiety (t = ,2.55, P = 0.0014) and depression levels (t = ,2.61, P = 0.012) than their healthy matched participants. Participants with higher anxiety and depression scores performed worse on the Movement Imitation Test. Conclusions,,, Ischemic damage of subcortical modular systems may affect praxis. [source] Battery for assessment of neuropsychological status (RBANS) in schizophrenia: a pilot study in the Spanish population,ACTA NEUROPSYCHIATRICA, Issue 1 2009Juan C. Sanz Objectives:, The aims of this study were to research the following issues in a Spanish population of patients with schizophrenia. (a) The sensitivity and reliability of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) to detect cognitive impairment in schizophrenia. (b) The convergent validity of RBANS on a larger battery of neuropsychological tests sensitive to the cognition disorders typically observed in schizophrenia. (c) The correlates of poor performance in RBANS with clinical features and illness severity. Method:, Thirty schizophrenia patients, 30 non-psychotic patients and 30 healthy participants were assessed using RBANS (form A). We administered a battery of neuropsychological tests and four scales to evaluate patient's clinical status. Results:, Schizophrenia patients and non-psychotic patients performed significantly worse than healthy controls on RBANS, and schizophrenia patients performed slightly worse than non-psychiatric controls, but this difference was not significant. Good inter-test reliability and concurrent validity were found. Only a moderate correlation between RBANS performance and illness severity was observed. Conclusions:, RBANS revealed coherence in identifying cognitive impairment in schizophrenia patients of a different cultural background, and it is shown to be a sensitive, valid and easy-to-perform tool for the neuropsychological assessment of Spanish patients with schizophrenia. [source] Lens autofluorescence is not increased at high altitudeACTA OPHTHALMOLOGICA, Issue 2 2010Line Kessel Abstract. Purpose:, To study the relation between ambient environmental ultraviolet radiation exposure and lens fluorescence. Methods:, Non-invasive lens fluorometry measurements were compared in healthy Bolivian and Danish subjects. Background ultraviolet radiation was 4.5 times higher in Bolivia than in Denmark. Results:, No significant differences in lens fluorescence or transmittance were found between Bolivian and Danish volunteers. Conclusion:, Age-corrected lens fluorescence and transmittance were comparable for healthy participants living at high altitude near the equator and healthy volunteers living at sea level at 55° northern latitude. These results suggest that lens ageing, as assessed by lens autofluorometry, is independent of exposure to ultraviolet radiation. [source] | ||||||||||||||||||||||||||||||||||