Blue light effect on EEG activity – The role of exposure timing and chronotype

There is growing evidence for monochromatic blue light effects. However, the role of individual differences in it has not yet been explored. The aim of this experiment was to examine whether chronotype could moderate the monochromatic blue light effect on electroencephalographic (EEG) activity with regard to the timing of exposure. The participants were 30 young male volunteers. A within-subjects counterbalanced design was applied. There were two light conditions comparable in luminance: Monochromatic blue light of 460 nm and polychromatic white light of 6.5 lux. EEG measurements were taken after 4 hours of exposure in the morning, afternoon, and evening. EEG spectral power was categorized into five frequency ranges: delta, theta, alpha1, alpha2, and beta. Chronotypes were assessed by the Morningness-Eveningness Questionnaire. A mixed analysis of variance was applied. Significant interactions between chronotype, light conditions, and the time of the day were found in theta and alpha1 bands after exposure to monochromatic blue light. These preliminary results indicated that in morning-oriented types the spectral power of theta and alpha1 EEG bands was higher in monochromatic blue light when compared to polychromatic white light in the afternoon hours than in the morning or the evening hours. These results may indicate a decrease in alertness in monochromatic blue light in the afternoon hours in morning-oriented types. This could point to the moderating role of individual differences in the monochromatic blue light effect.

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Germination responses of seeds of Desmodium triflorum

International Journal of Scientific Reports ◽

10.18203/issn.2454-2156.intjscirep20180392 ◽

2018 ◽

Vol 4 (2) ◽

pp. 19 ◽

Cited By ~ 1

Author(s):

Niroj Paudel ◽

Prakash Deep Rai

Keyword(s):

Seed Germination ◽

Blue Light ◽

White Light ◽

Red Light ◽

Light Condition ◽

Dark Condition ◽

Percentage Germination ◽

Negative Effect

Background: Germination of Desmodium triflorum is used for the scarification using the acid is valuable for the different light condition.Methods: The sample was collected as four month of interval of time and the seed is treated with acids with different time. Results: seeds scarified with sulfuric acids for 10 min before sowing had better germination than those scarified for 5 and 15 min. Among them light qualities, red and white light had slightly promoted effect whereas blue light and dark condition had slightly negative effect on seed germination.Conclusions: In comparison to blue light and dark condition, red light and white light were promoted to percentage germination indicating the role of phytochrome in seed germination of Desmodium triflorum.

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Seed Germination of Some Flower Species Under Influence of Different Light Conditions

Агрознање ◽

10.7251/agren1602183t ◽

2017 ◽

Vol 17 (2) ◽

pp. 183

Author(s):

Monika Tkalec ◽

Тijana Mirković ◽

Mario Mitrović ◽

Nada Parađiković ◽

Jasna Kraljičak ◽

...

Keyword(s):

Seed Germination ◽

Blue Light ◽

White Light ◽

Germination Rate ◽

Dianthus Caryophyllus ◽

Light Conditions ◽

Germination Energy ◽

Significant Difference ◽

Set Up ◽

Local Store

The aim of this study was to examine germination energy and seed germination rate of some flower species under influence of different light conditions. Seeds of Zinnia elegans Jacq., Dianthus caryophyllus L. and Callistephus chinensis (L.) Nees that were used in the research were purchased in local store. Experiment was set up in three replicates for each light treatment and each flower species. Petri dishes with seeds were placed in growth chamber under artificial white and blue light under 12hL/12hD photoperiod. Results showed no significant difference in germination energy and total germination of investigated flower species in respect of light. Zinnia seedlings were significantly longer on white light, while Dianthus seedlings were longer on blue light. Both, length and fresh weight of Callistephus seedlings were greater on white light. The absence of significant differences between measured parameters under examined light regimes suggests that germination of Zinnia, Dianthus and Callistephus is not photosensitive.

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Bumblebees land remarkably well in red–blue greenhouse LED light conditions

Biology Open ◽

10.1242/bio.046730 ◽

2020 ◽

Vol 9 (6) ◽

pp. bio046730 ◽

Cited By ~ 1

Author(s):

Lana J. de Vries ◽

Frank van Langevelde ◽

Coby van Dooremalen ◽

Ilse G. Kornegoor ◽

Martin J. Lankheet ◽

...

Keyword(s):

Plant Growth ◽

Blue Light ◽

White Light ◽

High Speed ◽

Bombus Terrestris ◽

Green Light ◽

Light Conditions ◽

Final Phase ◽

Negative Effects ◽

Leg Extension

ABSTRACTRed–blue emitting LEDs have recently been introduced in greenhouses to optimise plant growth. However, this spectrum may negatively affect the performance of bumblebees used for pollination, because the visual system of bumblebees is more sensitive to green light than to red–blue light. We used high-speed stereoscopic videography to three-dimensionally track and compare landing manoeuvres of Bombus terrestris bumblebees in red–blue light and in regular, broad-spectrum white light. In both conditions, the landing approaches were interspersed by one or several hover phases, followed by leg extension and touchdown. The time between leg extension and touchdown was 25% (0.05 s) longer in red–blue light than in white light, caused by a more tortuous flight path in red–blue light. However, the total landing duration, specified as the time between the first hover phase and touchdown, did not differ between the light conditions. This suggests that the negative effects of red–blue light on the landing manoeuvre are confined to the final phase of the landing.This article has an associated First Person interview with the first author of the paper.

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Elaborating the role of reflection and individual differences in the study of folk-economic beliefs

Behavioral and Brain Sciences ◽

10.1017/s0140525x18000274 ◽

2018 ◽

Vol 41 ◽

Author(s):

Kevin Arceneaux

Keyword(s):

Decision Making ◽

Individual Differences ◽

Cognitive Processes ◽

Evolutionary History ◽

Behavioral Responses ◽

History Of ◽

Economic Beliefs

AbstractIntuitions guide decision-making, and looking to the evolutionary history of humans illuminates why some behavioral responses are more intuitive than others. Yet a place remains for cognitive processes to second-guess intuitive responses – that is, to be reflective – and individual differences abound in automatic, intuitive processing as well.

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Variations Across the Menstrual Cycle in EEG Activity During Thinking and Mental Relaxation

Journal of Psychophysiology ◽

10.1027//0269-8803.13.3.163 ◽

1999 ◽

Vol 13 (3) ◽

pp. 163-172 ◽

Cited By ~ 7

Author(s):

R. Krug ◽

M. Mölle ◽

H.L. Fehm ◽

J. Born

Keyword(s):

Menstrual Cycle ◽

Divergent Thinking ◽

Spectral Power ◽

Plasma Concentrations ◽

Task Demands ◽

Menstrual Phase ◽

Convergent Thinking ◽

Eeg Activity ◽

Dimensional Complexity ◽

Mental Relaxation

Abstract Previous studies have indicated: (1) peak performance on tests of divergent creative thinking during the ovulatory phase of the menstrual cycle; (2) compared to convergent analytical thinking, divergent thinking was found to be associated with a distinctly increased dimensional complexity of ongoing EEG activity. Based on these findings, we hypothesized that cortical information processing during the ovulatory phase is characterized by an increased EEG dimensionality. Each of 16 women was tested on 3 occasions: during the ovulatory phase, the luteal phase, and menses. Presence of the phases was confirmed by determination of plasma concentrations of estradiol, progesterone, and luteinizing hormone. The EEG was recorded while the women performed: (1) tasks of divergent thinking; (2) tasks of convergent thinking; and (3) during mental relaxation. In addition to EEG dimensional complexity, conventional spectral power analysis was performed. Behavioral data confirmed enhanced creative performance during the ovulatory phase while convergent thinking did not vary across cycle phases. EEG complexity was higher during divergent than convergent thought, but this difference remained unaffected by the menstrual phase. Influences of the menstrual phase on EEG activity were most obvious during mental relaxation. In this condition, women during the ovulatory phase displayed highest EEG dimensionality as compared with the other cycle phases, with this effect being most prominent over the central and parietal cortex. Concurrently, power within the alpha frequency band as well as theta power at frontal and parietal leads were lower during the luteal than ovulatory phase. EEG results indicate that task demands of thinking overrode effects of menstrual cycle. However, with a less demanding situation, an ovulatory increase in EEG dimensionality became prominent suggesting a loosening of associative habits during this phase.

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Two Short Tests Fail to Detect Vigilance Decrements

European Journal of Psychological Assessment ◽

10.1027//1015-5759.17.1.48 ◽

2001 ◽

Vol 17 (1) ◽

pp. 48-55 ◽

Cited By ~ 6

Author(s):

Juan Botella ◽

María José Contreras ◽

Pei-Chun Shih ◽

Víctor Rubio

Keyword(s):

Individual Differences ◽

High Performance ◽

Selection Process ◽

Vigilance Task ◽

Air Traffic Controllers ◽

Job Selection ◽

Performance Deterioration ◽

Short Test ◽

Psychological Dimensions

Summary: Deterioration in performance associated with decreased ability to sustain attention may be found in long and tedious task sessions. The necessity for assessing a number of psychological dimensions in a single session often demands “short” tests capable of assessing individual differences in abilities such as vigilance and maintenance of high performance levels. In the present paper two tasks were selected as candidates for playing this role, the Abbreviated Vigilance Task (AVT) by Temple, Warm, Dember, LaGrange and Matthews (1996) and the Continuous Attention Test (CAT) by Tiplady (1992) . However, when applied to a sample of 829 candidates in a job-selection process for air-traffic controllers, neither of them showed discriminative capacity. In a second study, an extended version of the CAT was applied to a similar sample of 667 subjects, but also proved incapable of properly detecting individual differences. In short, at least in a selection context such as that studied here, neither of the tasks appeared appropriate for playing the role of a “short” test for discriminating individual differences in performance deterioration in sustained attention.

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Individual Differences in the Name Similarity Effect

Journal of Individual Differences ◽

10.1027/1614-0001/a000133 ◽

2014 ◽

Vol 35 (2) ◽

pp. 111-118

Author(s):

Daniel J. Howard ◽

Roger A. Kerin

Keyword(s):

Individual Differences ◽

Impression Management ◽

Interactive Effect ◽

Purchase Intentions ◽

Brand Attitude ◽

Self Monitoring ◽

Similarity Effect ◽

And Behavior ◽

Usage Context

The name similarity effect is the tendency to like people, places, and things with names similar to our own. Although many researchers have examined name similarity effects on preferences and behavior, no research to date has examined whether individual differences exist in susceptibility to those effects. This research reports the results of two experiments that examine the role of self-monitoring in moderating name similarity effects. In the first experiment, name similarity effects on brand attitude and purchase intentions were found to be stronger for respondents high, rather than low, in self-monitoring. In the second experiment, the interactive effect observed in the first study was found to be especially true in a public (vs. private) usage context. These findings are consistent with theoretical expectations of name similarity effects as an expression of egotism manifested in the image and impression management concerns of high self-monitors.

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The Role of Distress Disclosure Tendencies in the Experience and Expression of Laboratory-Induced Sadness

Journal of Individual Differences ◽

10.1027/1614-0001/a000222 ◽

2017 ◽

Vol 38 (1) ◽

pp. 55-62 ◽

Cited By ~ 1

Author(s):

Jeffrey H. Kahn ◽

Daniel W. Cox ◽

A. Myfanwy Bakker ◽

Julia I. O’Loughlin ◽

Agnieszka M. Kotlarczyk

Keyword(s):

Individual Differences ◽

Emotional Reactivity ◽

Subjective Experience ◽

Negative Emotion ◽

Theoretical Models ◽

Laboratory Research ◽

Emotion Words ◽

Distress Disclosure ◽

Computerized Text Analysis

Abstract. The benefits of talking with others about unpleasant emotions have been thoroughly investigated, but individual differences in distress disclosure tendencies have not been adequately integrated within theoretical models of emotion. The purpose of this laboratory research was to determine whether distress disclosure tendencies stem from differences in emotional reactivity or differences in emotion regulation. After completing measures of distress disclosure tendencies, social desirability, and positive and negative affect, 84 participants (74% women) were video recorded while viewing a sadness-inducing film clip. Participants completed post-film measures of affect and were then interviewed about their reactions to the film; these interviews were audio recorded for later coding and computerized text analysis. Distress disclosure tendencies were not predictive of the subjective experience of emotion, but they were positively related to facial expressions of sadness and happiness. Distress disclosure tendencies also predicted judges’ ratings of the verbal disclosure of emotion during the interview, but self-reported disclosure and use of positive and negative emotion words were not associated with distress disclosure tendencies. The authors present implications of this research for integrating individual differences in distress disclosure with models of emotion.

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