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A double-blind placebo controlled trial was carried out to examine the effects of supplementation with anti-oxidant vitamins on mental performance in the elderly. The participants were assigned to either placebo or vitamin groups and assessed at 4, 8 and 12 months. Blood samples were taken to determine vitamin levels at these times. The results showed little effect of supplementation on mental performance and few associations between plasma levels of the vitamins and mental functioning. These results are in contrast to results from assessment of mood, intelligence and cognitive failure which demonstrated beneficial effects of increased levels of vitamin C.

This study examined the effects of breakfast cereal and caffeinated coffee on working memory, attention, mood, and cardiovascular function. One hundred and forty-four volunteers (72 male, 72 female, mean age 21 years) were assigned to one of the groups formed by combining breakfast (cereal versus no breakfast) and caffeine (caffeinated versus decaffeinated coffee) conditions. The volunteers completed a baseline session between 0800 and 0845 h. The breakfast/caffeine administration took place between 0845 and 0915 h. They then completed another test session (starting at 0945) and had a coffee break at 1045, followed by a final session starting at 1145. The results showed that those who consumed breakfast cereal had a more positive mood at the start of the test sessions, performed better on a spatial memory task, and felt calmer at the end of the test session than those in the no breakfast condition. Ingestion of caffeine had no effect on initial mood or working memory, but it did improve encoding of new information and counteracted the fatigue that developed over the test session. Caffeine increased blood pressure and pulse rate, whereas breakfast cereal consumption only had an effect on pulse. Overall, these results confirm previous findings on the effects of breakfast and caffeine, and demonstrate distinct profiles for two common examples of early-morning food and drink, breakfast cereal and caffeinated coffee.

Abstract The present study examined whether volunteers with common colds showed impairments in objective and subjective indicators of alertness. All the volunteers (N = 81) were tested when healthy to provide baseline data for mood, simple and choice reaction time tasks, and an anti-saccadic eye movement task. When subjects developed a cold (N = 17) they returned to the laboratory and repeated the procedure. Volunteers (N = 64) who remained healthy over a 10-week period were recalled as controls. The results showed that those with colds felt significantly less alert and had significantly slower simple and choice reaction times and eye movements. This extends earlier research and shows that electrophysiological measures may also be of use in assessing the behavioral changes induced by upper respiratory tract illnesses.

An experiment was carried out to determine whether idazoxan, a drug which increases the turnover of central noradrenaline, removes the malaise (reduced alertness, slower psychomotor performance) associated with upper respiratory tract illness (URTI). Eighty-one volunteers were tested when healthy and 17 returned to the laboratory when they developed URTIs. Those who remained healthy were then recalled as a control group. Volunteers were tested before and after receiving either idazoxan (40 mg) or a lactose placebo. Idazoxan removed the URTI-induced slowing in a simple reaction time task and this group performed at a comparable level to the healthy group. No significant stimulant effect of idazoxan was found in the healthy subjects. The results suggest that at least part of the malaise induced by URTIs may reflect reductions in central noradrenaline and that this can be reversed by compounds such as idazoxan.

The present study examined the effects of anti-oxidant vitamin supplementation on mood and cognitive functioning in 205 volunteers (110 females, 95 males; age range: 60-80 years). In this randomised, double-blind, placebo-controlled study, the volunteers received either anti-oxidant supplementation (daily dosage 12mg/d β-carotene, 400 mg/d α-tocopherol and 500mg/d ascorbic acid) or placebo. The volunteers were followed up for 12 months. Vitamin levels were assessed from plasma samples. The primary outcome measures were subjective mood, self-reported cognitive failures, and measures of intelligence. These were measured at 4, 8 and 12 months. There were very few significant differences between the placebo and vitamin groups. Analysis of the effects of changes in vitamin levels on mood and cognition revealed significant effects of changes in vitamin C but not the other anti-oxidants. Increases in vitamin C were associated at 12 months with more positive mood, greater improvements in global assessments of intellectual functioning and a reduction in everyday errors of memory, attention and action. These effects were greatest for those volunteers who had a more negative mood and lower levels of cognitive function at baseline. Overall, results support earlier findings based on examination of dietary intake.

Previous research has shown that cessation of caffeine consumption may be associated with a distinct withdrawal syndrome, typified by an increase in headaches. Recent research suggests that low to moderate consumers of caffeine may report an increase in headaches if they perceive caffeine to have been withdrawn regardless of whether it has been or not. The present study provides additional support for the role of subjective perceptions in the caffeine withdrawal syndrome. Forty-three low caffeine consumers recorded the incidence of headaches when drinking caffeinated or decaffeinated beverages. When caffeine was withdrawn the incidence of headaches increased but this effect was only significant in those individuals who could discriminate whether they were consuming caffeinated or decaffeinated beverages. This result suggests a major role of subjective perceptions and expectancies in the caffeine withdrawal syndrome, a view that contrasts with the notion that a significant proportion of caffeine consumers are physically dependent upon caffeine.

The aim of the present study was to attempt to replicate and extend a recent result which showed that breakfast cereal consumption was associated with better mental health. The general population sample studied here (262 volunteers aged between 21 and 85 years, mean age: 60.9 years) was older than the sample in the previous study. The results showed that those who consumed breakfast cereal every day reported better mental and physical health than those who consumed it less frequently. This association was still present when demographic factors, indicators of lifestyle, such as smoking, or other aspects of diet were covaried. Further research is now required to elucidate the mechanisms underlying this robust association between daily breakfast cereal consumption and well-being.

Previous research has shown that both experimentally-induced and naturally occurring upper respiratory tract illnesses (URTIs) influence mood and mental functioning. None of the previous studies of naturally occurring colds has conducted appropriate virological assays to determine the nature of the infecting agent. This is an essential methodological step in studies of malaise associated with URTIs. The aim of this research was to investigate the effects of naturally occurring colds on mood and objective measures of performance. This was done by first conducting a cross-sectional comparison of 37 healthy people and 158 volunteers with colds and then a longitudinal study in which 100 volunteers developed colds and 87 remained healthy. Virological techniques were used to identify infecting agents and comparisons made across the different groups. The results showed that having a cold was associated with reduced alertness and slowed reaction times. These effects were observed both for colds where the infecting virus was identified and those where it was not. Similar effects were obtained for both rhinovirus and coronavirus colds. One may conclude that upper respiratory tract illnesses lead to a reduction in subjective alertness and impaired psychomotor functioning. This was true for both illnesses where the infecting agent was identified and for those clinical illnesses where no virus was detected. It is now important to identify the mechanisms linking infection and illness with the behavioural changes. Similarly, the impact of these effects on real-life activities such as driving needs examining. Finally, methods of treatment need to be developed which not only treat the local symptoms of the illnesses but remove the negative mood and the performance impairments. © 1998 Elsevier Science Ltd. All rights reserved.

Rigopoulou et al., We report the first results from a spectroscopic survey of the [C II] 158 μm line from a sample of intermediate redshift (0.2 1011.5 L ), using the Spectral and Photometric Imaging REceiver-Fourier Transform Spectrometer on board the Herschel Space Observatory. This is the first survey of [C II] emission, an important tracer of star formation, at a redshift range where the star formation rate density of the universe increases rapidly. We detect strong [C II] 158 μm line emission from over 80% of the sample. We find that the [C II] line is luminous, in the range (0.8-4) × 10 -3 of the far-infrared continuum luminosity of our sources, and appears to arise from photodissociation regions on the surface of molecular clouds. The L [C II]/L IR ratio in our intermediate redshift (U)LIRGs is on average 10 times larger than that of local ULIRGs. Furthermore, we find that the L [C II]/L IR and L [C II]/L CO(1-0) ratios in our sample are similar to those of local normal galaxies and high-z star-forming galaxies. ULIRGs at z 0.5 show many similarities to the properties of local normal and high-z star-forming galaxies. Our findings strongly suggest that rapid evolution in the properties of the star-forming regions of (U)LIRGs is likely to have occurred in the last 5 billion years. © 2014. The American Astronomical Society. All rights reserved., D.R. and G.E.M. acknowledge support from grant ST/K00106X/1 and the John Fell Oxford University Press (OUP) Research Fund (G.E.M.). This development has been supported by national funding agencies: CSA (Canada); NAOC (China); CEA, CNES, CNRS (France); ASI (Italy); MCINN (Spain); SNSB (Sweden); STFC, UKSA (UK); and NASA (USA).

This study examined the effects of smoking and smoking deprivation on the articulatory loop of working memory. Forty subjects (20 smokers and 20 non-smokers) performed tasks involving serial recall of letters on two occasions 1 week apart. In each test one part was conducted with articulatory suppression and the other without it. The smokers completed one test following 12 h of smoking deprivation, and the other after smoking a cigarette. The order of suppression/non-suppression conditions and the order of smoking and smoking deprivation were balanced across subjects. The results showed that deprived smokers performed significantly worse than both smoking smokers and non-smokers in the task without suppression. Although all the subjects performed significantly worse whilst under articulatory suppression, smoking status was not found to influence performance here. These results imply that smoking has the effect of returning the smoker to a comparable level of performance to that seen in non-smokers, and suggest that smoking abstinence has a negative effect when performance involves the articulatory loop.

An experiment was conducted to examine the effects of caffeine and noise on mood, mental performance and cardiovascular function. One hundred and six young adults (mean age 21·2 years) took part in the study. Subjects were assigned to one of six groups formed by combining noise/quiet and drink (caffeinated coffee, decaffeinated coffee and fruit juice) conditions. Subjects were familiarized with the tasks and then completed a pre-drink baseline session (conducted in the quiet). Subjects were then given either caffeinated coffee (1·5 mg/kg caffeine), decaffeinated coffee or fruit juice. Following consumption of the drink subjects were re-tested 1 h later, either in noise (75 dBA conglomerate noise, consisting of speech, music and machinery noise) or in quiet. The subjects exposed to noise felt more anxious and showed an increase in blood pressure. Their performance of a cognitive vigilance task also declined over time. There were no significant main effects of caffeine, although simple reaction time was quickest in the caffeinated coffee group. Caffeine did not modify the effects of noise on mood, cardiovascular functioning or sustained attention. Indeed, the only interaction between drinks and noise was found in recall and recognition memory tasks, with the caffeine/noise group having better memory performance than the decaffeinated/noise subjects. Overall, the results show that low levels of caffeine do not increase the behavioural and physiological changes observed in a stressful situation.

Rationale: Compared with healthy individuals, those with upper respiratory tract illnesses (URTIs) report reduced alertness and have slower reaction times. It is important to evaluate medication that can remove this behavioural malaise. Objectives: The aim of this study was to compare the effects of a combination of ibuprofen plus caffeine with ibuprofen and caffeine alone, and placebo on malaise associated with URTIs, as measured by psychomotor performance and mood testing. Methods: Volunteers were randomly assigned to one of four medication conditions as follows: 200 mg ibuprofen and 100 mg caffeine; 200 mg ibuprofen; 100 mg caffeine; placebo. A single oral dose was given and testing followed for 3 h. Efficacy variables were based on the volunteers' performance, measured by psychomotor performance and mood. Results: The pre-drug results confirmed that those with an URTI had a more negative mood and impaired performance. Results from the simple reaction time task, at both 55- and 110-min post-dosing, showed that a single-dose of caffeinated products (I200/C100 and CAF100) led to significantly faster reaction times than IBU200 and placebo. These effects were generally confirmed with the other performance tasks. Subjective measures showed that the combination of ibuprofen and caffeine was superior to the other conditions. There were no serious adverse events reported, and study medication was well tolerated. Conclusions: The results from the post-drug assessments suggest that a combination of ibuprofen and caffeine was the optimum treatment for malaise associated with URTIs in that it had significant effects on objective performance and subjective measures.

Stellar archeology shows that massive elliptical galaxies today formed rapidly about ten billion years ago with star formation rates above several hundreds solar masses per year (M_sun/yr). Their progenitors are likely the sub-millimeter-bright galaxies (SMGs) at redshifts (z) greater than 2. While SMGs' mean molecular gas mass of 5x10^10 M_sun can explain the formation of typical elliptical galaxies, it is inadequate to form ellipticals that already have stellar masses above 2x10^11 M_sun at z ~ 2. Here we report multi-wavelength high-resolution observations of a rare merger of two massive SMGs at z = 2.3. The system is currently forming stars at a tremendous rate of 2,000 M_sun/yr. With a star formation efficiency an order-of-magnitude greater than that of normal galaxies, it will quench the star formation by exhausting the gas reservoir in only ~200 million years. At a projected separation of 19 kiloparsecs, the two massive starbursts are about to merge and form a passive elliptical galaxy with a stellar mass of ~4x10^11 M_sun. Our observations show that gas-rich major galaxy mergers, concurrent with intense star formation, can form the most massive elliptical galaxies by z ~ 1.5., Comment: Appearing in Nature online on May 22 and in print on May 30. Submitted here is the accepted version (including the Supplementary Information), see nature.com for the final version

This chapter aims to provide a “cost–benefit” analysis of the effects of caffeine consumption. It starts by considering what caffeine is, sources of caffeine and levels of consumption. It then considers benefits of caffeine consumption and summarizes recent reviews on caffeine and: sports performance, removal of the effects of sleep deprivation, sustained operations, shift work, human error, and safety at work, mental health, and driving. The next sections consider effects of caffeine on children and adolescents and possible health effects of caffeine. Caffeine and dependence are discussed in the second part of the chapter, as is the issue of effects of caffeinated energy drinks. It is concluded that there are many beneficial effects of caffeine and that negative effects are restricted to consumption of high doses by susceptible individuals. Caffeine is almost certainly the most widely used drug of dependence in the world. Research on caffeine tells us little about the harmful effects of drugs of dependence and shows that dependence per se is not a problem.

Despite the large number of studies on caffeine and attention, interpretation is often difficult because of methodological weaknesses. In the present study, use of a small battery of tests with four key outcome measures, combined with an appropriate sample size, addresses many of these problems. This methodology was used to examine whether effects of caffeine (a dose of 2 mg/kg) could be explained in terms of reversal of the effects of caffeine withdrawal. This was achieved by examining effects in non-consumers ( N = 35), who could not be withdrawn, and also in a group of consumers ( N = 35) who had undergone withdrawal for a week and no longer reported symptoms of withdrawal. The results showed no effect of short-term withdrawal on the performance measures, even though subjective reports showed an increase in symptoms after withdrawal. In contrast, the caffeine challenge carried out on Day 8 showed that ingestion of caffeine was associated with faster simple reaction time, fewer long responses, greater detection of targets in the cognitive vigilance task, and faster encoding of new information. These results suggest that it is important to continue to investigate mechanisms underlying these effects of caffeine and to further evaluate the practical implications of such effects.

BackgroundDifferent definitions of chronic fatigue syndrome (CFS) have different psychiatric exclusion criteria and this affects the type and frequency of associated psychiatric morbidity found. The operational criteria for neuraesthenia in ICD–10 vary in this and other respects from the Centers for Disease Control and Prevention (CDC) criteria for CFS. Neuraesthenia and associated psychiatric morbidity in CDC-defined CFS are evaluated.MethodCFS subjects and controls were interviewed with the Schedule for the Clinical Assessment of Neuropsychiatry (SCAN). The computerised scoring program for SCAN (CATEG05) facilitates the assignment of operational definitions according to DSM–III–R and ICD–10. Subjects were re-interviewed with SCAN an average of 11 months later. No specific treatments or interventions were given during this period.ResultsThe majority of subjects fulfilled ICD–10 operational criteria for neuraesthenia and had two and a half times the rate of psychiatric morbidity as the healthy comparison group according to the CATEG05 Index of Definition (ID). Approximately 80% of subjects fulfilled both DSM–III–R and ICD–10 criteria for sleep disorders. There was a significant fall in the number of subjects fulfilling criteria for depression and anxiety disorders and a significant increase in the number of subjects with no diagnosis for DSM–III–R criteria over time. There were no significant changes over time for any diagnosis according to ICD–10 criteria or for overall levels of psychopathology as reflected in CATEG05 ID levels.ConclusionsThe ICD–10 ‘neuraesthenia’ definition identifies almost all subjects with CDC-defined CFS. Fifty per cent of CFS subjects also had depressive or anxiety disorders, some categories of which remit spontaneously over time.

An experiment was conducted to examine the effects of alcohol consumption and stress on mood, mental performance and cardiovascular function. One hundred and six young adults (mean age 21.2 years) took part in the study. The results showed that alcohol consumption and stress interact to influence performance but not mood. Different effects were obtained depending on whether one examined the total number of units consumed per week or the frequency of drinking alcohol, but in both cases the effects were selective, being found only with certain stress measures and in some aspects of performance. The pattern of results was, however, consistent enough to suggest that these were not chance effects. The number of alcohol units consumed and degree of negative affect in the last week interacted reliably in analyses of the memory tasks. High scores on both were associated with improved performance (relative to low scores on both), whereas a high score on one but not the other was associated with impaired performance. Two types of effect could be distinguished in these interactions: the first, found in the working memory tasks, reflected the personality differences in the various groups; the other, seen in the episodic memory tasks, was present even when personality and gender were statistically controlled. Frequency of alcohol usage and frequency of negative life events were found to interact in the simple reaction time data, with frequent drinkers who had experienced a large number of negative life events having the slowest reaction times.

The aim of the present research was to extend the earlier work of Donald Broadbent on the relationship between cognitive failures scores and the difference between performance of categoric search and focused attention tasks. Results from four experiments, involving over 400 subjects, replicated Broadbent's finding that there was a small negative correlation between level of cognitive failure and the difference in speed of responding in categoric search and focused attention choice reaction time tasks. However, consideration of correlated attributes of cognitive failure showed that this effect could be explained in terms of differences in trait anxiety. It was, however, possible to derive another measure from the tasks, which was correlated with cognitive failure but independent of anxiety. In contrast to the relationship initially described by Broadbent, the correlation between the new measure and cognitive failure proved less reliable, being modified by the different contextual factors in the various experiments.

Reviews of the effects of noise on performance carried out in the 1980s suggested that results depended on the type of noise, nature of the task, and characteristics of the person performing in noise. This general view has been confirmed in the recent meta-analysis and synthesis by Szalma and Hancock (2011). There are, however, some notable omissions from this review. For example, beneficial effects of noise in low alertness states receive no coverage, and yet these provide the strongest support for arousal theories. The importance of predictability and perceived control was also overlooked, yet relevant studies, especially those looking at aftereffects of noise, are crucial for explanations based on compensatory effort. Also neglected was research emphasizing the importance of examining the microstructure of responding and strategies of performance. Recent accounts emphasize the importance of considering the specific processes involved in carrying out a task and show that analyses based on gross characteristics present an inappropriate profile of effects. Laboratory studies of auditory distraction are now largely restricted to investigation of the effects of irrelevant speech. Noise and performance research has also moved toward field studies, including effects of chronic noise exposure on children. Future noise research is likely to focus on different noise parameters and performance outcomes, potentially leading to the investigation of different underlying mechanisms. This type of research will have clear implications for policy and practice.

Research has shown that extraverts performing a working memory task benefit more from caffeine than do introverts. The present study aimed to replicate this and extend our knowledge by using a lower dose of caffeine (65 mg) and a range of tasks related to different components of working memory. In addition, tasks assessing psychomotor speed and the encoding of new information were included to determine whether caffeine-extraversion interactions were restricted to working memory tasks. A double-blind design was used, with 128 participants being randomly assigned to caffeinated or de-caffeinated coffee conditions. The results showed that caffeine interacted with extraversion in the predicted direction for serial recall and running memory tasks. Caffeine improved simple reaction time and the speed of encoding of new information, effects which were not modified by extraversion. These results suggest possible biological mechanisms underlying effects of caffeine on cognitive performance.

Rationale: The present study examined whether caffeine would modify the behavioural effects of alcohol. Objectives: The aim of the study was to determine whether caffeine modifies the effects of alcohol on mood and psychomotor performance and to identify possible dose–response and temporal relationships. Methods: A double-blind study examined the effects of three successive lager drinks (330 ml each) in the early afternoon on mood and psychomotor performance assessed at 30-min intervals over a 2-h period. Participants carried out a baseline session and were then randomly assigned to one of six conditions formed by combining three different doses of caffeine (0, 62.5 and 125 mg per drink) with either no alcohol or 4.3 % alcohol. One hundred and forty-six young adults (65 male, 81 female; age range 18–30 years) participated in the study. Mood (alertness, hedonic tone and anxiety) was assessed before and after performing simple reaction time and choice reaction time tasks. Results: Alcohol was associated with higher hedonic tone (p

Summary Minor illnesses such as the common cold and influenza are frequent and widespread. As well as specific symptoms such as nasal problems and fever, these illnesses are associated with a behavioural malaise. One feature of this malaise is reduced alertness and this has been confirmed using subjective reports and objective measures of performance. Such effects have been obtained with both experimentally induced infections and in studies of naturally occurring illnesses. The mechanisms underlying the effects are unclear but possibly reflect effects of cytokines on the CNS which result in changes in neurotransmitter functioning that lead to reduced alertness. The malaise induced by these illnesses has many real-life consequences and activities such as driving and safety at work may be at risk. These illnesses not only have direct effects on performance and mood but also make the person more sensitive to effects of other negative influences such as noise, alcohol and prolonged work. Countermeasures include ingestion of caffeine and other drugs known to increase alertness.

Rationale: Chewing gum has been shown to reliably increase subjective alertness whereas the effects on attention are more variable. It has been suggested that chewing gum only enhances attention when the person has been performing a task for some time. Objectives: The current research aimed to investigate if time-on-task trends enhancing effects of chewing gum could be observed in alertness and attention during and following chewing. Methods: Study 1 used tests of reported mood, including reported mood, and tests of attention (categoric search, focussed attention, simple reaction time, and vigilance). These tasks were performed shortly after the start of chewing. Study 2 examined effects of previous and current chewing on reported alertness and the attention tests. Results: Study 1 showed that chewing gum increased reported alertness and hedonic tone and improved performance on the categoric search task. Chewing gum maintained reported alertness across sessions in study 2. In the first experimental session of study 2 gum improved categoric search performance, and during the second session gum broadened focus of attention and quickened vigilance reaction time. This effect on vigilance reaction time was moderated by time-on-task, with an initial negative effect being replaced by a positive effect. Discussion: The results confirm the robust effect of chewing gum on reported alertness and show that changes in the effects of chewing gum on attention require further investigation. Future research may also determine underlying mechanisms for an alerting effect.

Survey research has indicated that chewing gum is associated with reduced work stress, although experimental work has shown variable effects on stress and associated biomarkers. Previous intervention research has indicated a positive effect on stress and occupational well-being, although the intervention conditions used have lasted between three days and two weeks. An intervention method is described for examining the effect of gum on occupational well-being during single workdays, using both subjective measures and physiological biomarkers. The costs and benefits of different approaches to researching the effects of chewing gum are discussed.

Previous research has shown that people with the common cold report a more negative mood and psychomotor slowing. Recent research suggests that memory speed may also be impaired. This was examined in the study reported here. A prospective design was used and all participants (N = 200; half male, half female; mean age 21 years, range 18–30 years) carried out a baseline session when healthy. The test battery involved mood rating, simple and choice reaction time, verbal reasoning and semantic processing. Volunteers returned when they developed an upper respiratory tract illness (URTI) and repeated the test battery. If they remained healthy they were recalled as a control. One hundred and eighty-nine participants completed the study and 48 developed URTIs and 141 were in the healthy control group. Symptoms and signs suggested that those who were ill had colds rather than influenza. The results showed that those with colds reported lower alertness, a more negative mood, and psychomotor slowing. They were also slower at encoding new information and slower on the verbal reasoning and semantic processing tasks. The magnitude of the mood changes associated with being ill were correlated with symptom severity. The performance changes were not correlated with symptom severity, sleep duration or mood changes. Further research is now needed to elucidate the underlying mechanisms of the behavioral malaise associated with URTIs.

Previous research has indicated that chewing gum enhances reported alertness, but has variable effects on attention. Demand characteristics may explain these effects. The current study investigated the effects of gum and demand characteristics on attention and reported mood over time. Participants completed measures of mood and attention, with and without chewing gum. To manipulate demand characteristics, they were told that the hypothesised effect of gum was either positive or negative, or no hypothesis was mentioned. Attitudes towards gum were assessed pre- and post-manipulation. Gum increased reported alertness; this effect was only significant for positive and neutral demand characteristics. Vigilance accuracy was reduced for chewing gum, but only in the fourth minute of the task, and gum reduced focussed attention accuracy, but only for the first 64 trials. Demand characteristics did not moderate time-on-task effects. Gum improved selective attention. A positive effect on response organisation was observed; this was significant when demand characteristics and pre-test attitudes to gum were both negative. The results suggest that demand characteristics moderate effects on self-reported alertness and response organisation, but cannot explain time-on-task effects or variable main effects on other aspects of attention.

An experiment was carried out to determine whether a low dose of alcohol produced different behavioural effects in healthy volunteers to those suffering from an upper respiratory tract illness. Ninety-nine subjects were tested, with 48 subjects being assigned to the alcohol condition and 51 to the juice only condition. A dose of 1.5 ml of vodka per kg body weight was used and the alcohol manipulation was double-blind. Approximately half of the subjects in each condition were healthy and the others had upper respiratory tract illnesses, probably colds. Subjects with colds reported an increase in negative affect and were slower at performing psychomotor tasks. Few main effects of alcohol were obtained. Of major interest were the interactions between health status and alcohol conditions. The alcohol improved the mood of healthy subjects but produced greater negative moods in subjects with colds. Similarly, performance of selective and sustained attention tasks showed different effects of alcohol in healthy and ill subjects.

An experiment was carried out to examine the effects of caffeine and evening meals on sleep and performance, mood and cardiovascular functioning in the early morning of the next day. Forty-eight subjects were assigned to one of the four conditions formed by combining caffeine and meal conditions. Subjects in the caffeine condition were given 3 mg/kg caffeine in de-caffeinated coffee. The caffeine manipulation was double blind. Subjects in the meal condition were given a 3-course meal (∼ 1300 calories). Sleep was assessed by subjective ratings and these showed that both caffeine and consumption of the meal influenced sleep, but that there were no interactions between caffeine and meal conditions. Although caffeine disrupted sleep there was no evidence of performance or mood being impaired the next day. However, blood pressure was still higher the next day in subjects given caffeine the previous evening.

There has been considerable recent interest in associations between diet and subjective reports of wellbeing (stress, mental health, cognitive and physical functioning). Such effects have been considered across the lifespan and benefits often observed in all age groups. Effects of diet are often easier to detect in the elderly, either because of the longer period of consumption or the decline in functioning associated with aging. The present paper reports results from surveys examining associations between frequency of consumption of peas and beans and wellbeing. No significant associations were observed in younger samples but in the elderly more frequent consumption of peas and beans was associated with reduced stress, emotional distress, anxiety, depression and somatic symptoms. Further research is now required to examine underlying mechanisms and assess the practical implications of these findings.

Two studies are reported on the effects of drugs on the performance impairments induced by experimentally- produced colds. The first study examined the effects of zinc gluconate on choice reaction time, and showed that the zinc removed the cold-induced performance impairment. The second experiment used nedocromil sodium and, again, the drug was effective in reducing the drop in performance observed in volunteers with colds. While the precise mode of action of these compounds is unclear it is speculated that one mechanism involves changes in trigeminal stimulation, and this could be responsible for both the clinical efficacy and CNS effects of these drugs.

Two experiments were carried out to examine the effects of caffeine on performance, mood and cardiovascular function. The results showed that the effects of caffeine depended on the dose, time of administration, the function being examined and the impulsivity of the subject. Changes in blood pressure were only observed when a high dose (3 mg/kg) was used. The effects of this dose on performance depended on the impulsivity of the subject, with high impulsives performing worse in the de-caffeinated condition but getting a greater benefit from the caffeine. The high dose of caffeine also removed the post-lunch dip in sustained attention. The second experiment, which used a lower dose of caffeine (~60 mg), failed to demonstrate any caffeine x impulsivity or caffeine x time of day effects on performance. However, caffeine improved performance on a logical reasoning task and caffeine x time of day x impulsivity effects were found in analyses of visual search tasks. The mood data also support the view that the effects of caffeine depend on a combination of factors similar to those outlined for performance.

Previous research has shown that both experimentally induced upper respiratory tract illnesses (URTIs) and naturally occurring URTIs influence mood and performance. The present study investigated possible cognitive mechanisms underlying the URTI-performance changes. Those who developed a cold (N = 47) had significantly faster, but less accurate, performance than those who remained healthy (N = 54). Illness had no effect on manipulations designed to influence encoding, response organisation (stimulus-response compatilibility) or response preparation. Similarly, there was no evidence that different components of working memory were impaired. Overall, the present research confirms that URTIs can have an effect on performance efficiency. Further research is required to identify the physiological and behavioral mechanisms underlying these effects.

Anecdotal accounts suggest that colds and influenza may increase human error. This view is supported by laboratory studies of the effects of upper respiratory tract illnesses (URTIs) on performance efficiency, which have shown that both experimentally induced and naturally occurring URTIs reduce aspects of performance efficiency. The present research examined the relationship between accidents and URTIs by studying 923 patients attending an Accident and Emergency department at a time of year when upper respiratory tract viruses were circulating. The results revealed no significant associations between URTIs and workplace accidents, and, similarly, no significant associations emerged when all accidents were compared with other attenders. The only effect which was close to statistical significance was a protective effect of influenza against workplace accidents, which could be explained in terms of a person with influenza or who has recently had influenza being less likely to work and therefore less likely to be at risk of experiencing a workplace accident. Further research must examine this topic with different methodologies, such as selecting controls from fellow workers of the index case, and these studies will provide us with a clearer view as to whether or not there is an association between URTIs and workplace accidents.

Recent research has indicated that chewing gum can relieve perceptions of stress in an occupational sample (Smith, 2009). In the present study, 72 students completed 2 weeks of either chewing gum or refraining from chewing gum. They completed scales measuring perceived stress, anxiety, depression, and single item measures of work levels and tiredness. These were completed both pre- and post-treatment. Perceived stress decreased as a function of the amount of gum chewed. The chewing gum condition was also associated with a decrease in not getting enough academic work done. There were no significant effects of chewing gum on mental health outcomes. These results confirm some of findings from previous studies of chewing gum and stress in other samples.

An intervention study was carried out to examine the effects of chewing gum on occupational stress and related outcomes. 101 volunteers from Cardiff University completed the study. The results showed that chewing gum reduced stress (both at work and outside work), reduced fatigue, reduced anxiety and depression and led to a more positive mood. Chewing gum was also associated with perceptions of better performance (both at work and outside).

Well-being at work has been shown to be influenced by job characteristics and individual differences in coping styles. This study investigated the relationships between job demands, control, social support, efforts, rewards, coping, and attributional style in predicting anxiety, depression, and job satisfaction in a sample of 307 university employees from the UK. Results were compared to those from a sample of 120 members of the general population. Workplace demands, intrinsic and extrinsic effort, and negative coping and attributional behaviors were associated with high levels of depression and anxiety and low job satisfaction in university employees. Rewards, social support, job control, and positive coping and attributional behaviors were associated with lower levels of depression and anxiety and high job satisfaction. The study adds to the growing research on university samples by showing that a transactional approach should be adopted. This has implications for interventions and suggests that rather than just trying to change job characteristics one should identify at-risk individuals in this population and help them adopt appropriate positive coping styles.

Nineteen hospital pharmacies in Britain participated in a study of dispensing errors. All dispensing errors (errors detected outside the department) and a sample of dispensing incidents (errors detected as part of the checking process) were recorded using a standard data collection form over a period of six months. One hundred and seventy-eight errors and 1,500 incidents were analysed. The overall error rate was 18.1/100,000 dispensed items (range 2.9–49.1/100,000). The mean error rate was 11.5/100,000 items in hospitals where all dispensing is checked and 35/100,000 items in hospitals where only items dispensed by non-pharmacists are checked. There were also differences in type between errors and incidents −31.7 per cent of incidents involved incorrect directions on the label compared with 17.4 per cent of errors; 34.2 per cent of incidents involved the wrong drug or drug strength being dispensed compared with 45.5 per cent of errors. One hundred and forty-five different drugs were involved in the 178 errors, with three drugs being involved in six errors each (flucloxacillin, glyceryl trinitrate and frusemide). The results of this study can contribute to the preparation of risk management strategies for dispensing.

The present study examined the effects of sleep deprivation on performance, mood, and cardiovascular functioning in the late morning and early afternoon. The results showed that the sleep-deprived subjects felt less alert and detected fewer targets in a cognitive vigilance task. Selective impairments due to sleep deprivation were also observed in a logical reasoning task. There was little evidence to suggest that consumption of lunch altered these effects of sleep deprivation. However, individual differences in the effects of sleep deprivation were apparent, with trait anxiety being related to the changes in subjective alertness produced by sleep deprivation, and sleep-deprived extraverts showing greater performance impairments than the sleep-deprived introverts.

An experiment was carried out to examine the effects of coffee on performance and alertness in the day and at night. The results showed that caffeinated coffee had a beneficial effect on alertness and improved performance on a variety of tasks in both day and night sessions. The effects were often very large. For example, at night, consumption of caffeinated coffee produced comparable alertness ratings to the day-time ratings given when juice was drunk. In contrast to the effects of caffeinated coffee, the difference between the decaffeinated coffee and juice were small and variable. Overall, these results clearly demonstrate the beneficial effects of consuming caffeinated coffee, and show that this effect is comparable in the day and night.

Rationale: Recent research suggests that chewing gum may improve aspects of cognitive function and mood. There is also evidence suggesting that chewing gum reduces stress. It is important, therefore, to examine these two areas and to determine whether contextual factors (chewing habit, type of gum, and personality) modify such effects. Objectives: The aims of the present study were: (i) to determine whether chewing gum improved mood and mental performance; (ii) to determine whether chewing gum had benefits in stressed individuals; and (iii) to determine whether chewing habit, type of gum and level of anxiety modified the effects of gum. Subjects and methods: A cross-over study involving 133 volunteers was carried out. Each volunteer carried out a test session when they were chewing gum and without gum, with order of gum conditions counterbalanced across subjects. Baseline sessions were conducted prior to each test session. Approximately half of the volunteers were tested in 75 dBA noise (the stress condition) and the rest in quiet. Volunteers were stratified on chewing habit and anxiety level. Approximately, half of the volunteers were given mint gum and half fruit gum. The volunteers rated their mood at the start and end of each session and had their heart rate monitored over the session. Saliva samples were taken to allow cortisol levels (good indicator of alertness and stress) to be assayed. During the session, volunteers carried out tasks measuring a range of cognitive functions (aspects of memory, selective and sustained attention, psychomotor speed and accuracy). Results: Chewing gum was associated with greater alertness and a more positive mood. Reaction times were quicker in the gum condition, and this effect became bigger as the task became more difficult. Chewing gum also improved selective and sustained attention. Heart rate and cortisol levels were higher when chewing which confirms the alerting effect of chewing gum. Conclusions: Overall, the results suggest that chewing gum produces a number of benefits that are generally observed and not context-dependent. In contrast to some previous research, chewing gum failed to improve memory. Further research is now required to increase our knowledge of the behavioral effects of chewing gum and to identify the underlying mechanisms.

The research described in this paper examined the relationship between mood and experimentally-induced upper respiratory virus infections and illnesses. The first aim was to determine whether pre-challenge mood was related to susceptibility to infection and illness. There was no evidence of an association in any of the trials. A second aim of the research was to examine the nature of the mood changes induced by the different viruses. Subjects with influenza showed a general increase in negative affect. Those who developed a cold following challenge with a coronavirus reported a drop in arousal but little change in other aspects of mood. Colds following challenge with rhinoviruses and respiratory syncytial viruses produced little change in mood. There was little evidence of sub-clinical infections changing mood. However, mood changes were also reported after the symptoms of a coronavirus cold had gone. These results demonstrate selective effects of upper respiratory viruses on mood and show that t...

Idazoxan, an α 2-adrenoceptor antagonist, is an effective antidepressant with a mode of action different from that of conventional antidepressants. As it is used as an antidepressant it is important to know whether there are any unwanted CNS side effects. Study of its effects will also provide information on the relationship between noradrenergic function and mood and performance. Twelve normal male volunteers who were given the drug (40 mg orally three times daily for 21 days) were compared with 12 matched controls. A computerized test battery was used to assess mood and various aspects of memory and attention. Many of the tests of memory and attention in the battery have been widely used over the last 20 years, and in addition two new selective attention tasks were included. The subjects were tested 3 days before starting the drug, on days 3 and 17 while on the drug, and after they had stopped taking the drug (4 days after and 24 days after). Control subjects followed a similar testing schedule. The results showed that the drug had no effect on mood, logical reasoning, retrieval from semantic memory or sustained attention. However, the drug did improve one aspect of selective attention (the place repetition effect), although this effect was only observed on the third day on the drug. Overall, the results suggest that idazoxan produces selective performance improvements, and that the measures of selective attention used here may be more sensitive indicators of drug effects than some of the traditional tasks currently in use.

The aim of the present study was to examine the effects of consuming cereal bars, given either for breakfast or a mid-morning snack, on mood and memory. Thirty-two volunteers (16 males, 16 females; mean age, 20 years 9 months) were randomly assigned to one of four groups formed by combining breakfast (cereal bar versus no breakfast) and snack (cereal bar versus no snack) conditions. A baseline session was completed at 08:30 h followed by breakfast at 9:00 h, another test at 10:00 h, followed by a mid-morning snack and then a final test at 12:00 h. In each session, volunteers rated their mood and carried out four memory tasks: free recall; recognition memory; a verbal reasoning task; and a semantic processing task. The results showed that volunteers who consumed a cereal bar for breakfast felt more alert, happy and sociable and less anxious. In addition, they also recalled more words in a free recall task. When the cereal bar was consumed as a mid-morning snack, alertness and hedonic tone increased, especially in the group who received no breakfast. The group who had no breakfast reported reduced anxiety after consumption of the snack. Recall was also improved after the snack. These findings show that consuming cereal bars in the early and mid-morning leads to beneficial behavioural effects. The results confirm earlier research on effects of breakfast and extend our knowledge of effects of snacks. Consumption of cereal bars may have important practical applications especially in situations where preparation of breakfast is difficult.

The effects of three doses of interferon alpha (IFNα, 1.5 Mu, 0.5 Mu and 0.1 Mu) on performance, mood and physiological function were examined in a double-blind placebo controlled trial. The subjects given an injection of 1.5 Mu showed symptoms which closely resembled those seen in influenza, although most of the symptoms had gone by the next day. All of the doses of IFN reduced subjective ratings of alertness, but again this effect was only apparent on the day of challenge. Subjects given the 1.5 Mu injection were slower on two of the performance tasks (a simple reaction time task and a pegboard task) both on the day of challenge and the following day. None of the other tasks in the battery was impaired by any of the doses of IFN, either on the day of challenge or the following day. These results suggest that IFNα has selective effects on performance, and it is possible that IFN-induced changes in CNS function provide a mechanism through which viral infections influence behaviour.

This study examined the effects of the size of the meal on post-lunch changes in attention, mood, blood pressure and pulse. Thirty-five females subjects were tested before and after lunch. One group (n = 12) were than given a normal-sized lunch, another (n = 11) were given a lunch designed to contain 40% more energy than their individual requirement and the third group (n = 12) had a lunch with an energy content 40% less than the estimated requirement. After lunch all groups of subjects reported that they felt more feeble, dreamy and bored, and less alert, excited, clear-headed, energetic, quick-witted, friendly, sociable and elated. However, the size of the meal did not alter the extent of the pre/post-meal differences. Similarly, there was no effect of meal size on pulse rate or blood pressure, although pre/post-meal differences were observed. In contrast, subjects who had a larger lunch than normal made more errors on focussed attention and search tasks (especially the search task) than those who had a normal-sized lunch or one which was smaller than normal.