Gregory Neely

Overlap in prevalence between various types of environmental intolerance.

Environmental intolerance (EI) is characterized by attribution of several, multisystem symptoms to specific environmental exposures, such as exposure to odorous/pungent chemicals, certain buildings, electromagnetic fields (EMFs) and everyday sounds. The symptoms are medically unexplained, non-specific and the symptoms overlap between different types of EI. To approach the issue of underlying mechanisms the matter of overlap in prevalence between intolerances can provide valuable information. The aim of the study was to examine if the overlap between intolerance to odorous/pungent chemicals, certain buildings, EMFs and sounds is larger than the expected overlap if no association would exist between them. The study was using cross-sectional data from the Västerbotten Environmental Health Study in Sweden; a large questionnaire-based survey. 8520 adults (18-79 years) were randomly selected after stratification for age and sex, of whom 3406 (40%) participated. Individuals with the four types of intolerance were identified either through self-report, or by having been physician-diagnosed with a specific EI. The overlaps between the four EIs were greater than predictions based on coincidence for both self-reported and diagnosed cases (except for the overlap between diagnosed intolerance to sounds and EMFs). The results raise the question whether different types of EI share similar underlying mechanisms, or at least that the sufferers of EI share some predisposition to acquire the conditions.

Treating Major Depression with Physical Activity: A Systematic Overview with Recommendations

The purpose of this systematic overview was to determine the most effective mode and dose of physical activity (PA) for treating major depressive disorder (MDD), and to suggest guidelines and recommendations for clinicians. The selection process consisted of a comprehensive search that was conducted up until April 2014 in the following databases: PsycINFO, Medline, PubMed and Scopus. The inclusion criteria were: (1) a randomized controlled trial (RCT) design, (2) complete description of intensity, duration and frequency of the PA, (3) the participants had to be diagnosed with MDD according to Diagnostic Statistical Manual 4 th edition (DSM-IV) or International Classification of Disease tenth Revision (ICD-10) criteria (4) if the controls received any treatment, it had to be specified, (5) published after 1990, (6) consist of aerobic or anaerobic treatment PA, and (7) not be a pilotor preliminary study. A quality assessment of each study was conducted independently by two reviewers; this stringent selection process resulted in 12 reviewed studies. Conclusion: individually customized PA, for at least 30 minutes, preferably performed under supervision and with a frequency of at least three times per week is recommended when treating MDD. These recommendations must be viewed in light of the relatively few studies matching the inclusion criteria.

Cognitive After-effects of Vibration and Noise Exposure and the Role of Subjective Noise Sensitivity

Cognitive After‐effects of Vibration and Noise Exposure and the Role of Subjective Noise Sensitivity: Jessica K. Ljungberg, et al. National Institute for Working Life, Sweden—This study investigated the effects on attention performance after exposure to noise and whole‐body vibration in relation to subjective noise sensitivity. Sixteen high and 16 low sensitivity male students, as determined by the Weinstein Noise Sensitivity Questionnaire, participated in a within‐subjects experiment. Noise and vibration stimuli similar to those usually occurring in forestry vehicles were presented either individually, combined or not at all in four separate sessions lasting approximately 44 min. After exposure, participants completed an attention task and made subjective ratings of alertness. No main effect of noise sensitivity was observed in MANOVA, thus the data was pooled with the data from a pilot study using the exact same procedure without using a noise sensitivity inclusion criterion. The combined data revealed performance degradation in the attention task after exposure to vibration, regardless as to whether it was presented alone or in combination with noise. Increased ratings of alertness after vibration exposure and decreased ratings of alertness after noise exposure were also found. Neither synergistic nor antagonistic effects were observed from the combined noise and vibration exposure.

Heart rate variability during sedentary work and sleep in normal and sleep‐deprived states

The possibility of using heart rate variability (HRV) as an indicator of sleepiness was investigated by analysing heart rate (HR) activity and electroencephalography (EEG) recordings from 10 individuals who performed a monotonous attention task for 120 min in both sleep‐deprived and rested states. In both conditions, measurements were collected during 60 min of sleep immediately following a 120 min of non‐sleep (awake phase). Although HR decreased significantly in both the rested and the sleep‐deprived states during the awake phase, HR significantly changed sooner when subjects were sleep‐deprived than when they were rested. No significant changes in HRV were found during the awake phase; however, HRV correlated significantly with alpha and theta power densities when rested but not when sleep‐deprived. During the sleep phase, the total HRV and very low and low frequency HRV components significantly decreased approximately 40 min after sleeping in the sleep‐deprived condition. These HRV components were also significantly and negatively correlated with delta power densities. HRV does not seem to be a viable indicator of sleepiness; however, HRV may be useful for determining sleep stages.

Odor and noise intolerance in persons with self-reported electromagnetic hypersensitivity

Lack of confirmation of symptoms attributed to electromagnetic fields (EMF) and triggered by EMF exposure has highlighted the role of individual factors. Prior observations indicate intolerance to other types of environmental exposures among persons with electromagnetic hypersensitivity (EHS). This study assessed differences in odor and noise intolerance between persons with EHS and healthy controls by use of subscales and global measures of the Chemical Sensitivity Scale (CSS) and the Noise Sensitivity Scale (NSS). The EHS group scored significantly higher than the controls on all CSS and NSS scales. Correlation coefficients between CSS and NSS scores ranged from 0.60 to 0.65 across measures. The findings suggest an association between EHS and odor and noise intolerance, encouraging further investigation of individual factors for understanding EMF-related symptoms.

Stress and odor sensitivity in persons with noise sensitivity

Previous research has indicated that sensory sensitivity/intolerance to a specific modality may be part of a more general environmental hypersensitivity, and possibly mediated by stress. This study investigated the relationship between noise sensitivity, perceived stress, and odor sensitivity in a group of men. A quasi-experimental design was used. One-hundred and thirty-four male undergraduate students completed Weinsteins noise sensitivity scale from which a low-sensitivity group (n = 16) and a high-sensitivity (n = 16) group were formed. These two groups were screened for loss in auditory and olfactory detection sensitivity, and completed the perceived stress questionnaire (PSQ) and the chemical sensitivity scale (CSS). One-way analysis of variance and Spearman correlational analyses were performed. Significantly higher scores on the PSQ (P < 0.05) and the CSS (P < 0.05) were found in the high noise-sensitivity group compared to the low noise-sensitivity group. These findings raise the question of whether the relation between noise and odor sensitivity reflects a general environmental sensitivity.

Behavioral activation versus physical activity via the internet: A randomized controlled trial

BACKGROUND A major problem today is that only about fifty percent of those affected by depression seeks help. One way to reach more sufferers would be by offering easily accessible internet based treatments. The purpose of this study was to compare/evaluate four therapist supported internet administered treatments. METHOD/RESULTS Two hundred eighty six participants were included. The treatment period lasted twelve weeks, consisting of the following treatments: 1) physical activity without treatment rational, 2) physical activity with treatment rational, 3) behavioral activation without treatment rational and 4) behavioral activation with treatment rational. All groups (including a control-group) showed a significant decrease in depressive symptoms. When the treatment groups were pooled and compared to the control group, there were significant differences from pretest to posttest (Hedges gav treatment =1.01, control group =0.47). This held true also when each of the four treatment groups was compared to the control group, with one exception: Physical activity without treatment rationale. LIMITATIONS The differences between how many modules the participants completed could indicate that there are other factors than the treatments that caused the symptom reduction, however, the dose-response analysis did not detect any significant differences on account of modules completed. CONCLUSIONS The results support the positive effects of internet administered treatments for depression, and highlights the importance of psychoeducation, which tends to affect both the treatment outcome and the probability of remaining in treatment. These aspects need to be considered when developing and conducting new treatments for depression, since they would increase the likelihood of positive treatment outcomes.

'What's in a name?' 'No more than when it's mine own'. Evidence from auditory oddball distraction

Research of the distractor value of hearing the own name has shown that this self-referring stimulus captures attention in an involuntary fashion and create distraction. The behavioral studies are few and the outcomes are not always clear cut. In this study the distraction by own name compared to a control name was investigated by using a cross-modal oddball task in two experiments. In the first experiment, thirty-nine participants were conducting a computerized categorization task while exposed to, to-be ignored own and matched control names (controlling for familiarity, gender and number of syllables) as unexpected auditory deviant stimulus (12.5% trials for each name category) and a sine wave tone as a standard stimulus (75% of the trials). In the second experiment, another group of thirty-nine participants completed the same task but with the additional deviant stimulus of an irrelevant word added (10% trials for each deviant type and 70% trials with the standard stimulus). Results showed deviant distraction by exposure to both the irrelevant word, own and the control name compared to the standard tone but no differences were found showing that the own name captured attention and distracted the participants more than an irrelevant word or a control name. The results elucidate the role of the own name as a potent auditory distractor and possible limitations with its theoretical significance for general theories of attention are discussed.

Missing a meal: Effects on alertness during sedentary work

The purpose of this investigation was to evaluate the acute effects of missing a meal on alertness. The participants were ten university students between 20–29 years old, five females and five males. Participants were chosen on the basis of their good sleep and eating practices. Measurements were collected during an eight hour period starting at 8.00 AM on four separate days. During the test period, participants carried out their normal study activities while on separate days receiving either just breakfast, just lunch, both lunch and breakfast, or no meal at all. During the test period, EEG was monitored continuously while subjective ratings of performance and tiredness were collected every half-hour. The results showed that while there were neither physiological nor subjective indications of tiredness which could be attributed to meal consumption, subjective feelings of lack of energy and motivation was significantly more pronounced at the end of the workday when missing a meal or two.

Effects on spatial skills after exposure to low frequency noise

A study of spatial skills was conducted with 27 male and 27 female participants. The aim of the study was to examine the post-exposure effect of a complex low frequency noise (21 Hz) on a mental rotation task. It was hypothesised that reaction time and number of errors would increase after 20 minutes exposure to noise exposure compared to performance after a control condition, and that groups exposed to higher intensity noise would exhibit greater impairment. Three groups of participants were exposed to a control condition and a noise condition (either, 77, 81 or 86 dB (A)). After each exposure, subjects completed a mental rotation task where the stimulus consisted of one of three letters presented in five different rotations, showed either normally or mirrored. The participants were asked to respond as quickly and accurately as possible, affirmatively if the letter presented was not mirrored and negatively if it was mirrored. Statistical analysis revealed that the medium intensity level generated significant post-exposure effects while no effects were seen at the low or high intensity levels.