Effects of intensity and positional predictability of a visual stimulus on simple reaction time

There is a rich repertoire of methods for stress detection using various physiological signals and algorithms. However, there is still a gap in research efforts moving from laboratory studies to real-world settings. A small number of research has verified when a physiological response is a reaction to an extrinsic stimulus of the participant’s environment in real-world settings. Typically, physiological signals are correlated with the spatial characteristics of the physical environment, supported by video records or interviews. The present research aims to bridge the gap between laboratory settings and real-world field studies by introducing a new algorithm that leverages the capabilities of wearable physiological sensors to detect moments of stress (MOS). We propose a rule-based algorithm based on galvanic skin response and skin temperature, combing empirical findings with expert knowledge to ensure transferability between laboratory settings and real-world field studies. To verify our algorithm, we carried out a laboratory experiment to create a “gold standard” of physiological responses to stressors. We validated the algorithm in real-world field studies using a mixed-method approach by spatially correlating the participant’s perceived stress, geo-located questionnaires, and the corresponding real-world situation from the video. Results show that the algorithm detects MOS with 84% accuracy, showing high correlations between measured (by wearable sensors), reported (by questionnaires and eDiary entries), and recorded (by video) stress events. The urban stressors that were identified in the real-world studies originate from traffic congestion, dangerous driving situations, and crowded areas such as tourist attractions. The presented research can enhance stress detection in real life and may thus foster a better understanding of circumstances that bring about physiological stress in humans.

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“…The rising time of GSR decreases as the stimuli increases [73]. This implies that if the duration of GSR is greater, the stimulus is not intense.…”

Section: Methodology and Laboratory Experimentsmentioning

confidence: 99%

Detecting Moments of Stress from Measurements of Wearable Physiological Sensors

Kyriakou

Resch

Sagl

et al. 2019

Sensors

163

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“…Numerous studies, across various domains, using multiple modalities, have demonstrated the important role of stimulus intensity on an individual's reaction time [15], [19], [29], [30]. However, the attempt to map the mechanism of such a response using EEG following an electrical stimulus is an important and unique step in characterizing the sensorimotor pathways involved in the generation of augmented responses.…”

Section: Discussionmentioning

confidence: 99%

Electrophysiological Correlates of Changes in Reaction Time Based on Stimulus Intensity

et al. 2012

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BackgroundAlthough reaction time is commonly used as an indicator of central nervous system integrity, little is currently understood about the mechanisms that determine processing time. In the current study, we are interested in determining the differences in electrophysiological events associated with significant changes in reaction time that could be elicited by changes in stimulus intensity. The primary objective is to assess the effect of increasing stimulus intensity on the latency and amplitude of afferent inputs to the somatosensory cortex, and their relation to reaction time.MethodsMedian nerve stimulation was applied to the non-dominant hand of 12 healthy young adults at two different stimulus intensities (HIGH & LOW). Participants were asked to either press a button as fast as possible with their dominant hand or remain quiet following the stimulus. Electroencephalography was used to measure somatosensory evoked potentials (SEPs) and event related potentials (ERPs). Electromyography from the flexor digitorum superficialis of the button-pressing hand was used to assess reaction time. Response time was the time of button press.ResultsReaction time and response time were significantly shorter following the HIGH intensity stimulus compared to the LOW intensity stimulus. There were no differences in SEP (N20 & P24) peak latencies and peak-to-peak amplitude for the two stimulus intensities. ERPs, locked to response time, demonstrated a significantly larger pre-movement negativity to positivity following the HIGH intensity stimulus over the Cz electrode.DiscussionThis work demonstrates that rapid reaction times are not attributable to the latency of afferent processing from the stimulated site to the somatosensory cortex, and those latency reductions occur further along the sensorimotor transformation pathway. Evidence from ERPs indicates that frontal planning areas such as the supplementary motor area may play a role in transforming the elevated sensory volley from the somatosensory cortex into a more rapid motor response.

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“…Additionally, in Experiment 1, Brighter visual targets and ''bright'' auditory primes produced significantly faster correct responses than Darker targets and ''dark'' primes, irrespective of crossmodal congruency. We theorize that faster RTs in response to brighter stimuli (in both modalities) were the result of differences in intensity/arousal-luminance for visual targets (Carreiro, Haddad, & Baldo, 2011) and spectral center of gravity for auditory primes (Caclin, Giard, Smith, & McAdams, 2007;Wallmark, 2019a)-though future studies using a broader gradient of luminance levels for the targets and, perhaps, fully controlled synthetic tones are required to confirm this intuition.…”

Section: Discussionmentioning

confidence: 96%

Does Timbre Modulate Visual Perception? Exploring Crossmodal Interactions

Wallmark¹,

Nghiem

Marks

2021

Music Perception

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Musical timbre is often described using terms from non-auditory senses, mainly vision and touch; but it is not clear whether crossmodality in timbre semantics reflects multisensory processing or simply linguistic convention. If multisensory processing is involved in timbre perception, the mechanism governing the interaction remains unknown. To investigate whether timbres commonly perceived as “bright-dark” facilitate or interfere with visual perception (darkness-brightness), we designed two speeded classification experiments. Participants were presented consecutive images of slightly varying (or the same) brightness along with task-irrelevant auditory primes (“bright” or “dark” tones) and asked to quickly identify whether the second image was brighter/darker than the first. Incongruent prime-stimulus combinations produced significantly more response errors compared to congruent combinations but choice reaction time was unaffected. Furthermore, responses in a deceptive identical-image condition indicated subtle semantically congruent response bias. Additionally, in Experiment 2 (which also incorporated a spatial texture task), measures of reaction time (RT) and accuracy were used to construct speed-accuracy tradeoff functions (SATFs) in order to critically compare two hypothesized mechanisms for timbre-based crossmodal interactions, sensory response change vs. shift in response criterion. Results of the SATF analysis are largely consistent with the response criterion hypothesis, although without conclusively ruling out sensory change.

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Effects of intensity and positional predictability of a visual stimulus on simple reaction time

Cited by 12 publications

References 29 publications

Detecting Moments of Stress from Measurements of Wearable Physiological Sensors

Detecting Moments of Stress from Measurements of Wearable Physiological Sensors

Electrophysiological Correlates of Changes in Reaction Time Based on Stimulus Intensity

Does Timbre Modulate Visual Perception? Exploring Crossmodal Interactions

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