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Aging and depression have been found to be associated with poorer performance in mnemonic discrimination. In the current study, a two-response format mnemonic similarity test, Cognitive Drug Research MST, was used to compare these effects. Seventy-six participants were tested; with 52 participants in the young group, aged 18-35 years, and 24 participants in the elderly group, aged 55 years or older. Twenty-two young participants and 10 elderly participants met DSM-IV criteria for MDD or dysthymia. Age-related deficits were found for lure identification and speed of response. Differences in speed of responses to lure images were found for younger depressed participants, and depressive symptom severity was found to be negatively associated with lure identification accuracy in the elderly. These findings may be viewed as putative behavioral correlates of decreased pattern separation ability, which may be indicative of altered hippocampal neurogenesis in aging and depression. [ABSTRACT FROM AUTHOR]

Objective This study aimed to characterise, emotion perception deficits in symptomatic Huntington's disease (HD) via the use of event-related potentials (ERPs). Methods ERP data were recorded during a computerised facial expression task in 11 HD participants and 11 matched controls. Expression (scrambled, neutral, happy, angry, disgust) classification accuracy and intensity were assessed. Relationships between ERP indices and clinical disease characteristics were also examined. Results Accuracy was significantly lower for HD relative to controls, due to reduced performance for neutral, angry and disgust (but not happy) faces. Intensity ratings did not differ between groups. HD participants displayed significantly reduced visual processing amplitudes extending across pre-face (P100) and face-specific (N170) processing periods, whereas subsequent emotion processing amplitudes (N250) were similar across groups. Face-specific and emotion-specific derivations of the N170 and N250 ('neutral minus scrambled' and 'each emotion minus neutral', respectively) did not differ between groups. Conclusions Our data suggest that the facial emotion recognition performance deficits in HD are primarily related to neural degeneration underlying 'generalised' visual processing, rather than face or emotional specific processing. Significance ERPs are a useful tool to separate functionally discreet impairments in HD, and provide an important avenue for biomarker application that could more-selectively track disease progression. [ABSTRACT FROM AUTHOR]

This experiment explored the effects of hypnotic analgesia on painful stimuli in high and low susceptible participants (N = 33). Behavioural (target detection; RTs), subjective (pain ratings) and electrophysiological (SERP) responses of high and low susceptible participants were assessed during control, standard-hypnosis and hypnotic-analgesia conditions. The behavioural and subjective data showed that suggestion of hypnotic analgesia modulated the processing of painful stimuli, particularly in high susceptible participants. In contrast there were no significant changes in electrophysiological responses to these stimuli. Results in high susceptible participants demonstrate that hypnotic analgesia provides an important strategy for modulating experimentally induced pain. They also suggest that different brain mechanisms are involved in the processing of painful stimuli under hypnotic analgesia and attentional distraction instructions and support previous research findings that the differentiation of behavioural, subjective and electrophysiological responses may be a result of a dissociation between the processing of sensory information and the cognitive evaluation of that information. [ABSTRACT FROM AUTHOR]

This experiment explored the effects of hypnotic analgesia on painful stimuli in high and low susceptible participants (N = 33). Behavioural (target detection; RTs), subjective (pain ratings) and electrophysiological (SERP) responses of high and low susceptible participants were assessed during control, standard-hypnosis and hypnotic-analgesia conditions. The behavioural and subjective data showed that suggestion of hypnotic analgesia modulated the processing of painful stimuli, particularly in high susceptible participants. In contrast there were no significant changes in electrophysiological responses to these stimuli. Results in high susceptible participants demonstrate that hypnotic analgesia provides an important strategy for modulating experimentally induced pain. They also suggest that different brain mechanisms are involved in the processing of painful stimuli under hypnotic analgesia and attentional distraction instructions and support previous research findings that the differentiation of behavioural, subjective and electrophysiological responses may be a result of a dissociation between the processing of sensory information and the cognitive evaluation of that information. [ABSTRACT FROM AUTHOR]

Antidepressants targeting the serotonergic system have been shown to modulate biases in emotional processing. The effects of serotonergic modulation on the temporal course of emotional processing (accruing within milliseconds) are unknown. Furthermore, it is unknown how serotonin affects different stages of facial emotional processing. The current study investigated the effects of acute serotonin augmentation on event-related potential (ERP) measures associated with 'structural encoding' (N170) and emotion 'expression decoding' (N250 and a late slow-wave positive potential [LPP]) of happy and sad facial stimuli, relative to neutral facial stimuli. The study was a double-blind, placebo-controlled, cross-over design, in which 14 healthy male participants completed a facial recognition task under two acute treatment conditions: 1) placebo (PLB) and 2) 20 mg citalopram (CIT). ERP recording were conducted while subjects viewed neutral, happy and sad facial stimuli. Findings indicated that under PLB, the N170 was not modulated by valence (happy or sad versus neutral), but the N250 and LPP were enhanced for processing happy (relative to neutral) faces. Citalopram had no effect on the N170, but it enhanced the LPP for processing sad (relative to neutral) faces. These findings suggest that serotonin enhancement has selective and temporal effects on emotional face processing, with evidence for modulating processes associated with 'expression decoding' but not 'structural encoding'. The enhanced cortical response to perception of moderately intense sad facial expressions following citalopram administration may relate to the cognitive processing of the social relevance or significance of such ambiguous stimuli. [ABSTRACT FROM AUTHOR]

Fifty-four patients were treated with intravenous ampicillin and sulbactam in an open study of intra-thoracic and intra-abdominal infection. Thirty-one were treated with 500 mg each of the combination 6-hourly while 23 patients were given 1 g of ampicillin and 500 mg of sulbactam, 6-hourly. Thirteen of fourteen (93%) patients with severe respiratory tract infection and 22/26 (85%) patients in the intra-abdominal infection group responded clinically and bacteriologically. Seven patients with clinical sepsis (but not confirmed bacteriologically) improved on therapy. 50/55 (91%) clinical isolates from this study were eliminated. An increase in MIC was found in two cases. There were minimal side effects, pain at site of injection being the commonest complaint. [ABSTRACT FROM PUBLISHER]

A rare case of free double ileal perforation in previously asymptomatic and undiagnosed Crohn's disease of the terminal ileum is described. At operation, a primary resection and anastomosis of the diseased bowel was performed. The management of free perforation in Crohn's disease is discussed, together with a review of the literature. It is suggested that the absence of steroids in a previously undiagnosed case may favour primary resection and anastomosis. [ABSTRACT FROM PUBLISHER]

ABSTRACT: Nutrient management has become a major focus for watershed-scale planning to sustain or improve groundwater quality in certain areas. The USDA Natural Resources Conservation Service (NRCS) Watershed Science Institute (WSSI), in cooperation with a number of partners, is developing a process for creating unique, watershed-scale models to examine dynamic phosphorus (P) flows into, out of, and within watersheds using a mass balance approach. The Watershed Ecosystem Nutrient Dynamics (WEND) model tracks watershed P balances over time within each of the several land-use sectors. Long-term impacts of various strategic policy decisions on P cycling both within and export from watersheds can be modeled. The Winooski River Watershed in Vermont is a case watershed in which WEND has been used to evaluate the impacts of long-term strategies on nutrient use efficiency. The objective of this study was to describe the effects of three scenarios (status quo, increased rate of development, and increased conservation policies) on P cycling. The model showed increased water quality impairment over 80 years under the status quo and development scenarios. Under the conservation scenario, P movement into the drainage network was significantly reduced. This suggests that the WEND model could be adopted as an NRCS tool for improved watershed-scale P management. [ABSTRACT FROM AUTHOR]

The study addresses the effects of generalization descriptions on risk perceptions. In a 1-factorial online experiment, 629 participants were randomly allocated to one of three groups. Group G1 received an excerpt of an original press release from the International Agency for Research on Cancer (IARC) regarding mobile phones and cancer, classifying RF EMF as possibly carcinogenic to humans. Group G2 received an additional explanatory text module, and Group G3 received a rewritten text, with both G2 and G3 highlighting that the possible cancer risk only refers to mobile phones. Risk perceptions regarding cell phones and related personal devices, base stations, and high voltage power lines were used as dependent variables measured before and after text reading. Further, the degree to which participants generalized from cell phone-related to other RF EMF exposures was assessed to determine whether this was predictive of their post-text risk perceptions. Regarding risk perceptions, no differences between the three groups were observed after reading the presented texts. Instead, all three experimental groups indicated increased risk perceptions for all electromagnetic field sources. However, we found significant differences according to the prevailing risk generalization belief. Respondents expressing a strong risk generalization belief showed significantly higher risk perceptions for all tested EMF sources (except mobile phones) than subjects with a weak risk generalization belief., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The current study aimed to investigate how selective reporting of study results indicating increased health effects will influence its receiver's risk perception. Using the example of the Interphone Study from 2010 on mobile phone usage and cancer, an online experiment was conducted separating respondents into two groups. One group of subjects was informed selectively about a relationship between heavy mobile phone use and an elevated risk of glioma (brain cancer) only. The other group of subjects was informed about the full results of the analyses of glioma risk by cumulative call time, which suggests that other than for the heavy users, there were no statistically significant elevated risks related to mobile phone use. The results showed that selective reporting of risk information increased risk perception when compared to receiving the full information. Additionally, the selectively informed subjects revealed a stronger tendency towards overgeneralization of the 'elevated brain cancer risk' to all mobile phone users, although this did not extend to an overgeneralization to other electromagnetic field sources or differences in the perception of a usage time dependency for possible health risks. These results indicate that reporting of full results is an important factor in effective risk communication., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

The way in which risk communication messages are framed can influence recipients' risk perceptions. Despite this, there is a limited understanding of how framing is responsible for influencing risk perception. One particularly important element may be whether a risk communication message is framed as a completed 'risk assessment' (specifying a magnitude of risk to the public as a function of the exposure level), or as a 'hazard identification' (a statement regarding whether an environmental agent could in principle cause detrimental health effects in humans, without addressing whether such effects may occur in practice). The current study aimed to investigate for the first time whether framing a risk communication message regarding 'mobile phones and health' as a hazard identification or as a risk assessment affects the reader's risk perception. Using an online survey, participants were separated into three groups and shown either an original press release from the International Agency for Research on Cancer regarding mobile phones and cancer (Group 1), or the press release with additional text modules intended to frame the press release as either a risk assessment (Group 2) or a hazard identification (Group 3). The experimental manipulation was successful in that framing the message as a hazard identification reduced the number of people that believed the press release was a risk assessment, whereas framing it as a risk assessment was not able to increase the number of people who thought that it was a risk assessment. However, no differences in risk perception were found between the groups. In an attempt to ascertain the reason for this lack of framing effect on the radiofrequency electromagnetic fields risk perception measures, it was found that pre-existing interpretations of risk and hazard strongly predicted risk perception, regardless of experimental group. Participants who believed that the International Agency for Research on Cancer conducted a hazard identification perceived lower risks and were less convinced that radiofrequency electromagnetic field exposure from mobile phones increases cancer risks. The results of the study demonstrate the importance of understanding the distinction between a hazard identification and a risk assessment, and suggest that radiofrequency electromagnetic field risk communication needs to develop means for empowering the public to differentiate between hazards and risks., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Recent research has provided evidence to suggest that emotional stimuli may interfere with response inhibition, due to automatic capture of attention. Whilst previous studies have provided data regarding changes to event-related potentials (ERPs) in emotional Go/NoGo tasks, few studies to-date have utilized an emotional stop signal task (SST). Thirty-five participants were included in the study; 21 healthy controls and 14 depressed. An indirect emotional SST was employed, which consisted of the presentation of neutral, negative or positive visual images. The primary two-choice reaction time task required responding to frame colour (blue or green), whilst in 33% of trials an auditory stop signal was presented, with stop signal delay adjusted according to an adaptive tracking procedure. ERPs associated with both the primary visual task and the auditory SST were analysed using temporal principle components analysis (tPCA). In the primary task, reaction times were found to be slower for negative compared to neutral images. Stop signal reaction time (SSRT) was not found to be affected by image category or depression status. However, the NoGo-N2 component was found to be reduced for positive images, whilst the NoGo-P3 component was reduced for both positive and negative images in comparison to neutral images in the stop signal task. This effect was found to be enhanced for the depressed participants, indicating that inhibitory processing in the presence of positive stimuli may be inhibited to a greater extent in depressed individuals than in healthy controls. These findings provide further evidence for the ability of emotional valence and major depressive disorder to influence inhibitory processing., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Driving is a complex task, which can be broken down into specific cognitive processes. In order to determine which components contribute to drowsy driving impairments, the current study examined simulated driving and neurocognitive performance after one night of sleep deprivation. Nineteen professional drivers (age 45.3±9.1) underwent two experimental sessions in randomised order: one after normal sleep and one after 27h total sleep deprivation. A simulated driving task (AusEd), the psychomotor vigilance test (PVT), and neurocognitive tasks selected from the Cognitive Drug Research computerised neurocognitive assessment battery (simple and choice RT, Stroop Task, Digit Symbol Substitution Task, and Digit Vigilance Task) were administered at 10:00h in both sessions. Mixed-effects ANOVAs were performed to examine the effect of sleep deprivation versus normal sleep on performance measures. To determine if any neurocognitive tests predicted driving performance (lane position variability, speed variability, braking RT), neurocognitive measures that were significantly affected by sleep deprivation were then added as a covariate to the ANOVAs for driving performance. Simulated driving performance and neurocognitive measures of vigilance and reaction time were impaired after sleep deprivation (p<0.05), whereas tasks examining processing speed and executive functioning were not significantly affected by sleep loss. PVT performance significantly predicted specific aspects of simulated driving performance. Thus, psychomotor vigilance impairment may be a key cognitive component of driving impairment when sleep deprived. The generalisability of this finding to real-world driving remains to be investigated., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: Individuals with Major Depressive Disorder (MDD) tend to be more susceptible to distraction by negative emotional material than their non-depressed counterparts. This extends to an enhanced vulnerability to interference from mood-congruent stimuli during cognitive processing. The current study investigated the electrophysiological correlates of competing cognitive and emotional processing demands in MDD., Methods: Event-related alpha activity within the lower alpha 1 band was examined during the online information retention phase of a non-emotive WM task with extraneous emotional stimuli (positive, negative and neutral) presented as background images. EEG activity over posterior parietal cortex was compared between 15 acutely depressed and 16 never depressed right-handed women., Results: A valence specific dissociation in lower alpha 1 activity was observed between the two groups, consistent with greater attentional resource allocation to positive distracters in control participants and to negative distracters in MDD participants. No group differences were seen when neutral distracters were displayed., Conclusions: These results demonstrate that activity within the lower alpha 1 band is sensitive to competing emotional and cognitive processing demands and highlight the importance of posterior parietal regions in depression-related susceptibility to affective distractibility during cognitive processing., (Copyright © 2012 Elsevier B.V. All rights reserved.)

An impaired capacity to filter or 'gate' sensory information is a core deficit in cognitive function associated with schizophrenia. These deficits have been linked in part to N-methyl-d-aspartate (NMDA) receptor dysfunction. An association between high levels of glycine, a positive allosteric modulator of the NMDA receptor, and sensorimotor gating impairments (i.e. prepulse inhibition (PPI) deficit) have been reported in animal models of schizophrenia as well as patients with schizophrenia. This study examined the acute effects of modulating the glycine site of the NMDA receptor (with high-dose glycine) on sensory gating as measured by PPI. Sixteen healthy male subjects (final sample size of 12) participated in a double-blind, placebo-controlled, crossover design in which each subject was tested under two acute treatment conditions separated by at least a 5-day washout period; placebo and 0.8 g/kg glycine. PPI was recorded 45 min post treatment using electromyography of the eye-blink response. Relative to placebo, high-dose glycine significantly impaired sensorimotor gating as demonstrated by a decrease in PPI (t(11) = -2.983, p < 0.05). Administration of a high dose of glycine is associated with impairments in PPI supporting earlier observations in animals and patients with schizophrenia. This result, when taken together with findings in patients, suggests that high synaptic levels of glycine may have some clinically relevant detrimental effects and suggests a potential dissociation of clinical symptomatology and sensory information processing as a function of NMDA receptor modulation in schizophrenia.

Objective: This study examined sensory and cognitive processing in adolescents, young adults and older adults, when exposed to 2nd (2G) and 3rd (3G) generation mobile phone signals., Methods: Tests employed were the auditory 3-stimulus oddball and the N-back. Forty-one 13-15 year olds, forty-two 19-40 year olds and twenty 55-70 year olds were tested using a double-blind cross-over design, where each participant received Sham, 2G and 3G exposures, separated by at least 4 days., Results: 3-Stimulus oddball task: Behavioural: accuracy and reaction time of responses to targets were not affected by exposure. Electrophysiological: augmented N1 was found in the 2G condition (independent of age group). N-back task: Behavioural: the combined groups performed less accurately during the 3G exposure (compared to Sham), with post hoc tests finding this effect separately in the adolescents only. Electrophysiological: delayed ERD/ERS responses of the alpha power were found in both 3G and 2G conditions (compared to Sham; independent of age group)., Conclusion: Employing tasks tailored to each individual's ability level, this study provides support for an effect of acute 2G and 3G exposure on human cognitive function., Significance: The subtlety of mobile phone effect on cognition in our study suggests that it is important to account for individual differences in future mobile phone research., (Copyright © 2011 International Federation of Clinical Neurophysiology. All rights reserved.)

Lateralized differences in frontal alpha power in individuals with major depressive disorder (MDD) are thought to reflect an aberrant affective processing style. However research into anterior alpha asymmetry and MDD has often produced conflicting results. The current study aimed to investigate whether individualized alpha bandwidths provide a more sensitive measure of anterior alpha asymmetry in MDD than the traditional fixed 8-13 Hz alpha band. Resting EEG was recorded from 34 right-handed female participants (18 controls, 16 MDD). Each participant's Individual Alpha Frequency was used to delineate a broad individualized alpha band and three individualized narrow alpha sub-bands: lower alpha1, lower alpha 2 and upper alpha. Activity within the broad and narrow individualized bandwidths and within the traditional fixed alpha band were used to compare a) controls and acutely depressed individuals and b) medicated and unmedicated MDD participants. Individualizing and subdividing the alpha bandwidth did not add appreciably to the sensitivity of anterior alpha asymmetry in MDD as no significant differences in lateralized alpha power between controls and MDD participants were observed in any alpha bandwidth. This finding was consistent under two reference schemes and across multiple scalp locations. Within the MDD group, antidepressant use was associated with significantly greater right than left hemispheric power in the lower alpha 1 band. The relevance of this finding is discussed in relation to the electrophysiological correlates of antidepressant medication use, lateralized differences in affective processing and treatment resistant MDD.

Background: EEG studies examining 'resting' state (i.e. non-task) state brain activity in major depressive disorder (MDD) have reported numerous abnormalities within the alpha bandwidth. These findings are discussed extensively within affective disorders literature but their relationship to functional aspects of depressive psychopathology remains unclear. Investigating alpha modulation during active cognitive processing may provide a more targeted means of relating aberrant alpha activity to specific aspects of depression symptomatology. Alpha activity is reliably modulated during working memory (WM) processing and WM impairments are a common neuropsychological consequence of MDD. Moreover, it has been suggested that alpha activity reflects internally mediated inhibitory process and attenuated inhibition has been suggested to contribute to WM inefficacy., Aim: The current investigation examined whether alpha was modulated differently in MDD participants during WM processing and whether the pattern of alpha activity was consistent with impairments in inhibitory processes., Method: Event related synchronisation (ERS) within the upper alpha band over the retention interval of a modified Sternberg WM task was examined in 15 acutely depressed and 15 never depressed right-handed female participants., Results: MDD participants displayed greater upper alpha ERS than controls during the online information maintenance component of WM processing. This was evident over left, but not right, parieto-occipital cortex., Conclusion: The results are consistent with increased inhibition of extraneous material during WM processing in depression. This may reflect a neurobiological compensation strategy whereby additional neural resources are required to achieve comparable performance accuracy during effortful cognitive processing in MDD., (Copyright © 2010 Elsevier B.V. All rights reserved.)

The present study was conducted to determine whether adolescents and/or the elderly are more sensitive to mobile phone (MP)-related bioeffects than young adults, and to determine this for both 2nd generation (2G) GSM, and 3rd generation (3G) W-CDMA exposures. To test this, resting alpha activity (8-12 Hz band of the electroencephalogram) was assessed because numerous studies have now reported it to be enhanced by MP exposure. Forty-one 13-15 year olds, forty-two 19-40 year olds, and twenty 55-70 year olds were tested using a double-blind crossover design, where each participant received Sham, 2G and 3G exposures, separated by at least 4 days. Alpha activity, during exposure relative to baseline, was recorded and compared between conditions. Consistent with previous research, the young adults' alpha was greater in the 2G compared to Sham condition, however, no effect was seen in the adolescent or the elderly groups, and no effect of 3G exposures was found in any group. The results provide further support for an effect of 2G exposures on resting alpha activity in young adults, but fail to support a similar enhancement in adolescents or the elderly, or in any age group as a function of 3G exposure., (2010 Wiley-Liss, Inc.)