Sensory Events Research Articles

Using event-related brain potentials to evaluate motor-auditory latencies in virtual reality.

Actions in the real world have immediate sensory consequences. Mimicking these in digital environments is within reach, but technical constraints usually impose a certain latency (delay) between user actions and system responses. It is important to assess the impact of this latency on the users, ideally with measurement techniques that do not interfere with their digital experience. One such unobtrusive technique is electroencephalography (EEG), which can capture the users' brain activity associated with motor responses and sensory events by extracting event-related potentials (ERPs) from the continuous EEG recording. Here we exploit the fact that the amplitude of sensory ERP components (specifically, N1 and P2) reflects the degree to which the sensory event was perceived as an expected consequence of an own action (self-generation effect). Participants (N = 24) elicit auditory events in a virtual-reality (VR) setting by entering codes on virtual keypads to open doors. In a within-participant design, the delay between user input and sound presentation is manipulated across blocks. Occasionally, the virtual keypad is operated by a simulated robot instead, yielding a control condition with externally generated sounds. Results show that N1 (but not P2) amplitude is reduced for self-generated relative to externally generated sounds, and P2 (but not N1) amplitude is modulated by delay of sound presentation in a graded manner. This dissociation between N1 and P2 effects maps back to basic research on self-generation of sounds. We suggest P2 amplitude as a candidate read-out to assess the quality and immersiveness of digital environments with respect to system latency.

Multimodal Temporal Pattern Discrimination Is Encoded in Visual Cortical Dynamics.

Discriminating between temporal features in sensory stimuli is critical to complex behavior and decision-making. However, how sensory cortical circuit mechanisms contribute to discrimination between subsecond temporal components in sensory events is unclear. To elucidate the mechanistic underpinnings of timing in primary visual cortex (V1), we recorded from V1 using two-photon calcium imaging in awake-behaving mice performing a go/no-go discrimination timing task, which was composed of patterns of subsecond audiovisual stimuli. In both conditions, activity during the early stimulus period was temporally coordinated with the preferred stimulus. However, while network activity increased in the preferred condition, network activity was increasingly suppressed in the nonpreferred condition over the stimulus period. Multiple levels of analyses suggest that discrimination between subsecond intervals that are contained in rhythmic patterns can be accomplished by local neural dynamics in V1.

Responses to Sensory Events in Daily Life in Children with Cerebral Palsy from a Parent Reported Perspective and in a Swedish Context.

The motor disorders of cerebral palsy (CP) are often accompanied by sensory disturbances, but knowledge of their relationship to motor functioning is sparse. This study explored responses to sensory events in relation to spastic subtype and motor functioning in children with CP. Parents of 60 children with CP (unilateral: 18, bilateral: 42) with GMFCS levels I:29, II:13, III:15 and IV:3 of mean age 12.3 years (3.7 SD) participated. The parents (n = 55) rated their children´s responses with the norm-referenced questionnaire Child Sensory Profile-2© (CSP-2©), Swedish version, incorporating nine sections and four sensory processing patterns/quadrants, and replied (n = 57) to two additional questions. On the CSP-2©, thirty (55%) of the children were reported to have responses "much more than others" (>2 SD) in one or more of the sections and/or quadrants and 22 (40%) in the section of Body Position, overrepresented by the children with bilateral CP. The additional questions revealed that a greater proportion of children at GMFCS levels III-IV compared to level I frequently were requested to sit/stand up straight (14/17 versus 6/26, p < 0.001) and were sound sensitive at a younger age (14/17 versus 10/26, p = 0.005). The findings of this study highlight the sensory aspects of motor functioning in children with spastic CP.

Probabilistic integration of preceding responses explains response bias in perceptual decision making

Expectations of sensory information change not only how well but also what we perceive. Even in an unpredictable environment, the brain is by default constantly engaged in computing probabilities between sensory events. These estimates are used to generate predictions about future sensory events. Here, we investigated the predictability of behavioral responses using three different learning models in three different one-interval two-alternative forced choice experiments with either auditory, vestibular, or visual stimuli. Results indicate that recent decisions, instead of the sequence of generative stimuli, cause serial dependence. By bridging the gap between sequence learning and perceptual decision making, we provide a novel perspective on sequential choice effects. We propose that serial biases reflect the tracking of statistical regularities of the decision variable, offering a broader understanding of this phenomenon.

Principles of nociceptive coding in the anterior cingulate cortex

The perception of pain is a multidimensional sensory and emotional/affective experience arising from distributed brain activity. However, the involved brain regions are not specific for pain. Thus, how the cortex distinguishes nociception from other aversive and salient sensory stimuli remains elusive. Additionally, the resulting consequences of chronic neuropathic pain on sensory processing have not been characterized. Using invivo miniscope calcium imaging with cellular resolution in freely moving mice, we elucidated the principles of nociceptive and sensory coding in the anterior cingulate cortex, a region essential for pain processing. We found that population activity, not single-cell responses, allowed discriminating noxious from other sensory stimuli, ruling out the existence of nociception-specific neurons. Additionally, single-cell stimulus selectivity was highly dynamic over time, but stimulus representation at the population level remained stable. Peripheral nerve injury-induced chronic neuropathic pain led to dysfunctional encoding of sensory events by exacerbation of responses to innocuous stimuli and impairment of pattern separation and stimulus classification, which were restored by analgesic treatment. These findings provide a novel interpretation for altered cortical sensory processing in chronic neuropathic pain and give insights into the effects of systemic analgesic treatment in the cortex.

Impaired perception of temporal contiguity between action and effect is associated with disorders of agency in schizophrenia

Delusions of control in schizophrenia are characterized by the striking feeling that one's actions are controlled by external forces. We here tested qualitative predictions inspired by Bayesian causal inference models, which suggest that such misattributions of agency should lead to decreased intentional binding. Intentional binding refers to the phenomenon that subjects perceive a compression of time between their intentional actions and consequent sensory events. We demonstrate that patients with delusions of control perceived less self-agency in our intentional binding task. This effect was accompanied by significant reductions of intentional binding as compared to healthy controls and patients without delusions. Furthermore, the strength of delusions of control tightly correlated with decreases in intentional binding. Our study validated a critical prediction of Bayesian accounts of intentional binding, namely that a pathological reduction of the prior likelihood of a causal relation between one's actions and consequent sensory events-here captured by delusions of control-should lead to lesser intentional binding. Moreover, our study highlights the import of an intact perception of temporal contiguity between actions and their effects for the sense of agency.

Validation of "Neurit.Space": Three Digital Tests for the Neuropsychological Evaluation of Unilateral Spatial Neglect.

Patients suffering from Unilateral Spatial Neglect (USN) fail to pay attention to, respond to, and report sensory events occurring in the contralesional side of space. The traditional neuropsychological assessment of USN is based on paper-and-pencil tests, whose data recording and scoring may be subjected to human error. The utilization of technological devices can be expected to improve the assessment of USN. Therefore, we built Neurit.Space, a modified digital version of three paper-and-pencil tests, widely used to detect signs of USN, namely: Bells Cancellation, Line Bisection and Five Elements Drawing Test. Administration and data processing is fully automatic. Twelve right brain-damaged patients (six with and six without USN) and 12 age- and education-balanced healthy participants were enrolled in the study. All participants were administered both the computerized and the paper-and-pencil versions of the tests. The results of this preliminary study showed good sensitivity, specificity, and usability of Neurit.Space, suggesting that these digital tests are a promising tool for the evaluation of USN, both in clinical and in research settings.

Ventral striatum dopamine release encodes unique properties of visual stimuli in mice.

The mesolimbic dopamine system is an evolutionarily conserved set of brain circuits that plays a role in attention, appetitive behavior, and reward processing. In this circuitry, ascending dopaminergic projections from the ventral midbrain innervate targets throughout the limbic forebrain, such as the ventral striatum/nucleus accumbens (NAc). Dopaminergic signaling in the NAc has been widely studied for its role in behavioral reinforcement, reward prediction error encoding, and motivational salience. Less well characterized is the role of dopaminergic neurotransmission in the response to surprising or alerting sensory events. To address this, we used the genetically encoded dopamine sensor dLight1 and fiber photometry to explore the ability of striatal dopamine release to encode the properties of salient sensory stimuli in mice, such as threatening looming discs. Here, we report that lateral NAc (LNAc) dopamine release encodes the rate and magnitude of environmental luminance changes rather than visual stimulus threat level. This encoding is highly sensitive, as LNAc dopamine could be evoked by light intensities that were imperceptible to human experimenters. We also found that light-evoked dopamine responses are wavelength-dependent at low irradiances, independent of the circadian cycle, robust to previous exposure history, and involve multiple phototransduction pathways. Thus, we have further elaborated the mesolimbic dopamine system's ability to encode visual information in mice, which is likely relevant to a wide body of scientists employing light sources or optical methods in behavioral research involving rodents.

The sense of smell in contemporary social sciences and human environment

AbstractAcross the ages, attitudes towards particular senses and their hierarchization have shifted. The sense of smell is an element of almost every person's experience. Its impact is physical, psychological and social. Up to this day, smell has been an important element of social interactions, influencing social reception and the quality of interpersonal contacts. Although smell has not always been an object of researchers’ interests, and often its importance has been intentionally depreciated, the tension between disqualification and embrace of olfactory data has not stopped the development of osmological research, also in the social sciences. The first sociologist to pay attention to the important role of senses in the social process was Georg Simmel. Thanks to an innovative approach to senses as social entities, he changed not just the perspective on sensory events but also laid the foundations for the specialist area of the sociology of the senses. This text attempts at introducing the reader to the origins and evolution of the sociology of the senses, placing special attention on the sense of smell, as well as how the ongoing ‘aromatization of culture’ process is opening up a large field of sociological research.

Hippocampal conjunctive and complementary CA1 populations relate sensory events to movement

Hippocampal CA1 neurons respond to sensory stimuli during enforced immobility, movement, and their transitions in a new conveyor belt task. Head-fixed mice were exposed to light flashes or air streams while at rest, spontaneously moving, or running a fixed distance. Two-photon calcium imaging of CA1 neurons revealed that 62% of 3341 imaged cells were active during one or more of 20 sensorimotor events. Of these active cells, 17% were active for any given sensorimotor event, with a higher proportion during locomotion. The study found two types of cells: Conjunctive cells that were active across multiple events, and complementary cells that were active only during individual events, encoding novel sensorimotor events or their delayed repetitions. The configuration of these cells across changing sensorimotor events may signify the role of hippocampus in functional networks integrating sensory information with ongoing movement making it suitable for movement guidance.

Neural correlates of aftereffects induced by adaptations to single and average durations.

Duration perception can be heavily distorted owing to repetitive exposure to a relatively long or short sensory event, often causing a duration aftereffect. Here, we used a novel procedure to show that adaptations to both single and average durations produced the duration aftereffect. Participants completed a duration reproduction task (Experiment 1) or a duration category rating task (Experiment 2) after long-term adaptations to a stimulus of medium duration and to stimuli of averagely medium duration. We found that adaptations to both single and average durations resulted in duration aftereffects. The simultaneously recorded functional magnetic resonance imaging (fMRI) data revealed that the reduction in neural activity due to long-term adaptation to single duration was observed in the right supramarginal gyrus (SMG) of the parietal lobe, while adaptation to average duration resulted in fMRI adaptations in the left postcentral gyrus (PCG) and middle cingulate gyrus (MCG). At the individual level, the magnitude of the behavioral aftereffect was positively correlated with the magnitude of fMRI adaptation in the right SMG after adaptation to single duration, while there were no significantly positive correlations between the behavioral aftereffect and fMRI adaptations in the left PCG and MCG. These results suggest that there are different neural mechanisms for aftereffects caused by adaptations to single and average durations.

An Assessment of Level of Attention and Concentration of High School Students in a Selected School, Chengalpattu District, Tamilnadu, India

Background: Attention is the concentration of consciousness upon one object rather than upon on other.Concentration is the mental effort placed on sensory or mental events deliberate mental effort on what is mostimportant in a given situation. Here the study conducted to assess the knowledge or assess the concentration andattention level in the high school students or effectiveness teaching on how to get concentration and attentionfocused on the high school subjects and the a ttention is a important to used to learning new things. It focus on thenatural of learning in education system in human beings without the concentration and attention leading to thefailures of learning some sorts of information at a particular things. The attention is very important so the studyreveals that effective of attention and assesses the level of concentration of high school students.Objectives: To assess the level of attention of high school students, to assess the level of concentration of highschool students and to associate the level of attention and concentration of high school students with their selecteddemographic variablesMaterials and Methods: Quantitative descriptive research approach was used in this study. 140 high school students(8th&amp; 9th standard) was selected by using randomized sampling technique in selected school in Chengalpattu district.A valid study questionnaire was used to collect data on socio-demographic characteristics of high school students,attention was assessed by using attention control scale and concentration was assessed by using concentrationassessment scale of the high school students. Data were analyzed by Inferential and descriptive statistics.Results: The study shows that the mean score was 1.90, standard deviation was 0.615 on the aspect of level ofattention and the mean score was 1.79, standard deviation was 0.560 on the aspect of level of concentration of highschool students. 61.4% of the high school students had average attention, 64.3% of the high school students hadaverage concentration.Conclusion: Assessment on level of attention and concentration of high school students shows that most of thehigh school students had average attention and the most of the high school students had average concentration.

A perceptual glitch in serial perception generates temporal distortions

Precisely estimating event timing is essential for survival, yet temporal distortions are ubiquitous in our daily sensory experience. Here, we tested whether the relative position, duration, and distance in time of two sequentially-organized events—standard S, with constant duration, and comparison C, with duration varying trial-by-trial—are causal factors in generating temporal distortions. We found that temporal distortions emerge when the first event is shorter than the second event. Importantly, a significant interaction suggests that a longer inter-stimulus interval (ISI) helps to counteract such serial distortion effect only when the constant S is in the first position, but not if the unpredictable C is in the first position. These results imply the existence of a perceptual bias in perceiving ordered event durations, mechanistically contributing to distortion in time perception. We simulated our behavioral results with a Bayesian model and replicated the finding that participants disproportionately expand first-position dynamic (unpredictable) short events. Our results clarify the mechanisms generating time distortions by identifying a hitherto unknown duration-dependent encoding inefficiency in human serial temporal perception, something akin to a strong prior that can be overridden for highly predictable sensory events but unfolds for unpredictable ones.

Altered fronto-central theta-gamma coupling in major depressive disorder during auditory steady-state responses

ObjectiveNeural oscillations during sensory and cognitive events interact at different frequencies. However, such evidence in major depressive disorder (MDD) remains scarce. We explored the possible abnormal neural oscillations in MDD by analyzing theta-phase/gamma-amplitude coupling (TGC). MethodsResting-state and auditory steady-state response (ASSR) electroencephalography recordings were obtained from 35 first-episode MDD and 35 healthy controls (HCs). TGC during rest, ASSR stimulation, and ASSR baseline between and within groups were analyzed to evaluate MDD alterations. Receiver operating characteristic (ROC), TGC comparison between MDD severity subgroups (mild, moderate, major), and correlations were investigated to determine the potential use of altered TGC for identifying MDD. ResultsIn MDD, left fronto-central TGC decreased during stimulation, while right fronto-central TGC increased during baseline. The area under ROC curve for altered TGC was 0.863. Furthermore, during stimulation, moderate and major MDD groups exhibited significantly lower TGC than mild group, and fronto-central TGC was negatively correlated with depression scale scores. ConclusionsOur results provided the first evidence for an abnormal TGC response of fronto-central regions in MDD during an ASSR task. Importantly, altered TGC may be promising biomarkers of MDD. SignificanceOur findings enhance the understanding of physiological mechanisms underlying MDD and aid in its clinical diagnosis.

Sonic Piety in Early New England

Abstract This article reinterprets New England's 1720s Singing Controversy as a sensory event that altered the nature of puritan sonic piety in early New England. Far from a parochial peculiarity in the history of American music, the 1720s singing reforms were part of broader challenges to a previous way of knowing-an epistemology, or, in this context, an “acoustemology.”

The positive valence system, adaptive behaviour and the origins of reward.

Although the hey-day of motivation as an area of study is long past, the issues with which motivational theorists grappled have not grown less important: i.e. the development of deterministic explanations for the particular tuning of the nervous system to specific changes in the internal and external environment and the organisation of adaptive behavioural responses to those changes. Here, we briefly elaborate these issues in describing the structure and function of the 'positive valence system'. We describe the origins of adaptive behaviour in an ascending arousal system, sensitive to peripheral regulatory changes, that modulates and activates various central motivational states. Associations between these motivational states and sensory inputs underlie evaluative conditioning and generate the representation of the 'unconditioned' stimuli fundamental to Pavlovian conditioning. As a consequence, associations with these stimuli can generate Pavlovian conditioned responses through the motivational control of stimulus event associations with sensory and affective components of the valence system to elicit conditioned orienting, consummatory and preparatory responses, particularly the affective responses reflecting Pavlovian excitation and inhibition, arousal and reinforcement, the latter used to control the formation of habits. These affective processes also provoke emotional responses, allowing the externalisation of positive valence in hedonic experience to generate the goal or reward values that mediate goal-directed action. Together these processes form the positive valence system, ensure the maintenance of adaptive behaviour and, through the association of sensory events and emotional responses through consummatory experience, provide the origins of reward.

When more is less: Adding action effects to reduce crosstalk between concurrently performed tasks

Dual-task costs are thought to reflect the architecture of the cognitive processes that guide voluntary action. Thus, manipulations that affect dual-task costs can provide insight into how we represent and select behavior as well as allow us to better design machines and controls for safer, more efficient performance. This line of research has revealed that the sensory events that follow the responses (i.e., action effects) can affect dual-task performance even though the sensory events occur after the actions are produced. The present study assessed three hypotheses regarding how action effects impact dual-task performance: a monitoring bottleneck, central stage shortening, and crosstalk. Across two experiments, we manipulated the content of two concurrently-performed tasks: a visual task that used either spatial or nonspatial stimuli (Experiment 1) and an auditory task that used responses with or without experimentally-induced auditory action effects (Experiments 1 and 2). In Experiment 1, dual-task costs were reduced when experimentally-induced auditory action effects were present, independent of the content of the visual task. In Experiment 2, the dual-task costs depended on the content of the experimentally-induced action effects, such that costs were larger when action effects emphasized ordinal (number) information, which overlapped with the unmanipulated action effects from the visual spatial task. Strikingly, dual-task costs were reduced when added, post-response events supported greater separation between task representations relative to when no post-response events were added. These results support the crosstalk hypothesis, as action effects appear to alter task representations so that they emphasize different types of information, reducing the degree of crosstalk.

Synthetic fertilizers alter floral biophysical cues and bumblebee foraging behavior.

The use of agrochemicals is increasingly recognized as interfering with pollination services due to its detrimental effects on pollinators. Compared to the relatively well-studied chemical toxicity of agrochemicals, little is known on how they influence various biophysical floral cues that are used by pollinating insects to identify floral rewards. Here, we show that widely used horticultural and agricultural synthetic fertilizers affect bumblebee foraging behavior by altering a complex set of interlinked biophysical properties of the flower. We provide empirical and model-based evidence that synthetic fertilizers recurrently alter the magnitude and dynamics of floral electrical cues, and that similar responses can be observed with the neonicotinoid pesticide imidacloprid. We show that biophysical responses interact in modifying floral electric fields and that such changes reduce bumblebee foraging, reflecting a perturbation in the sensory events experienced by bees during flower visitation. This unveils a previously unappreciated anthropogenic interference elicited by agrochemicals within the electric landscape that is likely relevant for a wide range of chemicals and organisms that rely on naturally occurring electric fields.

ANALGESIC ACTIVITY TEST OF WARU (Hibiscus tiliaceus L.) LEAVES ETHANOL EXTRACT IN MALE WHITE MISCULES (Mus musculus)

Herbal remedies in therapy have been used in the treatment of pain since time immemorial. Pain is a sensory and emotional event that causes discomfort due to tissue damage. Most of the analgesics used in modern medicine have side effects on either the gastro-intestinal tract or the nervous system. Empirically waru leaves have been used as traditional medicine. The purpose of this study was to evaluate the analgesic effect of the ethanol extract of waru leaf and compare it with mefenamic acid tablets and then measured by the plantar test infra red (IR) 96 nm. Twenty five mice were divided into five groups. Three of them were treated with ethanol extract of waru leaves with doses of 100, 200, 300 mg/kgbw, 0.5% Na-CMC (negative control), and 500 mg Mefenamic Acid tablets (positive control). Infrared pain induction was performed every 10 minutes for 60 minutes. The maximum analgesic activity was indicated by a dose of 300 mg/kg body weight extract at 60 minutes which was 23.8 where the effectiveness was almost the same as the standard drug Mefenamic Acid, which was 24.3 while the dose of 200 mg/kgBB was 20.9 and 100 mg/kgBW was 19.9. The data obtained were then processed using one way ANOVA. The conclusion of the study revealed that hibiscus leaf (Hibiscus tiliaceus L.) has significant analgesic properties, especially in higher doses

Can the Perceived Timing of Multisensory Events Predict Cybersickness?

Humans are constantly presented with rich sensory information that the central nervous system (CNS) must process to form a coherent perception of the self and its relation to its surroundings. While the CNS is efficient in processing multisensory information in natural environments, virtual reality (VR) poses challenges of temporal discrepancies that the CNS must solve. These temporal discrepancies between information from different sensory modalities leads to inconsistencies in perception of the virtual environment which often causes cybersickness. Here, we investigate whether individual differences in the perceived relative timing of sensory events, specifically parameters of temporal-order judgement (TOJ), can predict cybersickness. Study 1 examined audiovisual (AV) TOJs while Study 2 examined audio-active head movement (AAHM) TOJs. We deduced metrics of the temporal binding window (TBW) and point of subjective simultaneity (PSS) for a total of 50 participants. Cybersickness was quantified using the Simulator Sickness Questionnaire (SSQ). Study 1 results (correlations and multiple regression) show that the oculomotor SSQ shares a significant yet positive correlation with AV PSS and TBW. While there is a positive correlation between the total SSQ scores and the TBW and PSS, these correlations are not significant. Therefore, although these results are promising, we did not find the same effect for AAHM TBW and PSS. We conclude that AV TOJ may serve as a potential tool to predict cybersickness in VR. Such findings will generate a better understanding of cybersickness which can be used for development of VR to help mitigate discomfort and maximize adoption.