Stimulus-response Patterns Research Articles

Stimulus-Response Patterns: The Key to Giving Generalizability to Text-Based Depression Detection Models.

Text content analysis for depression detection using machine learning techniques has become a prominent area of research. However, previous studies focused mainly on analyzing the textual content, neglecting the fundamental factors driving text generation. Consequently, existing models face the challenge of poor generalization to out-of-domain data as they struggle to capture the crucial features of depression. To address this, we propose a novel computational perspective of "stimulus-response patterns" that brings us closer to the essence of clinical diagnosis of depression. Adopting this computational perspective allows us to conceptually unify diverse datasets and generalize this perspective to common datasets in the field. We introduce the Stimulus-Response Patterns-aware Network (SRP-Net) as an exemplary approach within this computational perspective. To assess the performance of the SRP-Net, we constructed a multi-stimulus dataset and conducted experimental evaluations, demonstrating its exceptional cross-stimulus generalizability. Furthermore, we demonstrated the promising performance of SPR-Net in real medical scenarios and conducted an interpretability analysis of the stimulus-response patterns. Our research investigates the critical role of stimulus-response patterns in enhancing the generalizability of text-based depression detection models, which can potentially facilitate data-driven depression detection to approach the diagnostic accuracy of psychiatrists.

Synapse-type-specific competitive Hebbian learning forms functional recurrent networks

Cortical networks exhibit complex stimulus-response patterns that are based on specific recurrent interactions between neurons. For example, the balance between excitatory and inhibitory currents has been identified as a central component of cortical computations. However, it remains unclear how the required synaptic connectivity can emerge in developing circuits where synapses between excitatory and inhibitory neurons are simultaneously plastic. Using theory and modeling, we propose that a wide range of cortical response properties can arise from a single plasticity paradigm that acts simultaneously at all excitatory and inhibitory connections-Hebbian learning that is stabilized by the synapse-type-specific competition for a limited supply of synaptic resources. In plastic recurrent circuits, this competition enables the formation and decorrelation of inhibition-balanced receptive fields. Networks develop an assembly structure with stronger synaptic connections between similarly tuned excitatory and inhibitory neurons and exhibit response normalization and orientation-specific center-surround suppression, reflecting the stimulus statistics during training. These results demonstrate how neurons can self-organize into functional networks and suggest an essential role for synapse-type-specific competitive learning in the development of cortical circuits.

Cortical reactivations predict future sensory responses.

Many theories of offline memory consolidation posit that the pattern of neurons activated during a salient sensory experience will be faithfully reactivated, thereby stabilizing the pattern1,2. However, sensory-evoked patterns are not stable but, instead, drift across repeated experiences3-6. Here, to investigate the relationship between reactivations and the drift of sensory representations, we imaged the calcium activity of thousands of excitatory neurons in the mouse lateral visual cortex. During the minute after a visual stimulus, we observed transient, stimulus-specific reactivations, often coupled with hippocampal sharp-wave ripples. Stimulus-specific reactivations were abolished by local cortical silencing during the preceding stimulus. Reactivations early in a session systematically differed from the pattern evoked by the previous stimulus-they were more similar to future stimulus response patterns, thereby predicting both within-day and across-day representational drift. In particular, neurons that participated proportionally more or less in early stimulus reactivations than in stimulus response patterns gradually increased or decreased their future stimulus responses, respectively. Indeed, we could accurately predict future changes in stimulus responses and the separation of responses to distinct stimuli using only the rate and content of reactivations. Thus, reactivations may contribute to a gradual drift and separation in sensory cortical response patterns, thereby enhancing sensory discrimination7.

The relationship between perseverative thinking, proactive control, and inhibition in psychological distress: a study in a women’s cohort

Cognitive control is a core feature of several mental disorders. A recent account poses that health problems may derive from proactive forms of cognitive control that maintain stress representation over time. The working hypothesis of the present study is that psychological distress is caused by the tendency to select a particular maladaptive self-regulation strategy over time, namely perseverative thinking, rather than by transient stimulus–response patterns. To test this hypothesis, we asked 84 women to carry out a battery of standardized questionnaires regarding their tendency to undertake perseverative thinking and their level of psychological distress, followed by cognitive tasks measuring the tendency to use proactive versus reactive control modality and disinhibition. Through a series of mediation analyses, we demonstrate that the tendency to use proactive control correlates with psychological distress and that this relation is mediated by perseverative thinking. Moreover, we show that the relation between low inhibitory control and psychological stress is more strongly mediated by perseverative thinking than impulsiveness, a classical construct that focuses on more transient reactions to stimuli. The present results underline the importance of considering psychological distress as the consequence of a maladaptive way of applying control over time, rather than the result of a general deficit in cognitive control abilities.

Functional sophistication in human escape

Animals including humans must cope with immediate threat and make rapid decisions to survive. Without much leeway for cognitive or motor errors, this poses a formidable computational problem. Utilizing fully immersive virtual reality with 13 natural threats, we examined escape decisions in N= 59 humans. We show that escape goals are dynamically updated according to environmental changes. The decision whether and when to escape depends on time-to-impact, threat identity and predicted trajectory, and stable personal characteristics. Its implementation appears to integrate secondary goals such as behavioral affordances. Perturbance experiments show that the underlying decision algorithm exhibits planning properties and can integrate novel actions. In contrast, rapid information-seeking and foraging-suppression are only partly devaluation-sensitive. Instead of being instinctive or hardwired stimulus-response patterns, human escape decisions integrate multiple variables in a flexible computational architecture. Taken together, we provide steps toward a computational model of how the human brain rapidly solves survival challenges.

Autonomic nervous system and postural control regulation during orthostatic test as putative markers of physical resilience among community-dwelling older adults

IntroductionWe examined whether autonomic nervous system (ANS) and postural control regulation during orthostatic test reflect physical resilience by studying their associations with maximal walking speed and mortality. MethodsThe participants were community-dwelling Finnish men (n = 303) and women (n = 386) aged 75, 80, and 85 years at baseline. Systolic and diastolic blood pressure (BP), heart rate, heart rate variability (HRV), respiratory rate, and postural sway were obtained using a digital sphygmomanometer, a single-channel ECG, and thigh- and chest-worn accelerometers. Linear and Cox regression models were used to estimate the associations of the physiological indices with maximal 10-m walking speed and 5-year mortality separately for sexes. ResultsBetter maintenance of BP under orthostatic stress was associated with faster walking speed in women and lower mortality hazard in men. Greater HRV in terms of low frequency power and lower respiration rate in supine position and smaller orthostatic changes in these were associated with faster walking speed especially in women. Less postural sway after standing up was associated with faster walking speed in women (−0.057, SE 0.022, p = 0.011) and more postural sway with increased mortality hazard in men (HR 1.71, 95 % CI 1.20–2.43) even after controlling for BP responses. ConclusionsIn addition to ANS regulation at rest and under stress, adaptation of postural control system to orthostasis may be used in quantifying older adults' physical resilience. Wearable sensors capturing stimulus-response patterns and natural fluctuations of body functions may provide opportunities to monitor and incorporate different subsystems' resilience also in free-living conditions.

Learning and Synaptic Plasticity in 3D Bioengineered Neural Tissues

Learning is integral to an organism's capacity to adapt to complex changes within its environment. Our understanding of the fundamental mechanisms that underlie learning within biological systems has historically been reliant upon the measurement of established nervous systems and their dissociated parts. However, advances in biomaterials and tissue engineering have made it possible to design and construct artificial neural substrates de novo, building iterative brain models to identify functional cause-effect relationships in vitro. And with the emergence of increasingly complex physiological response patterns among organoids and other laboratory-grown neural tissues, it has become relevant to ask what minimal features of cognition, if any, might be present within said substrates. One approach toward a study of minimal cognition in vitro is to operationalize a basic form of learning and assess information-processing features associated with the system under study. In the present work, we demonstrate that a 3D bioengineered neural tissue model can be habituated with patterned injections of current. Evoked-potentials following injections displayed features of non-associative learning including spontaneous recovery which was transient and reversible. Massed and distributed applications of current contributed to differential effects upon the expression of immediate early genes (IEGs) and, in particular, those regulating early growth response (EGR) transcriptional factors. These are known to facilitate synaptic plasticity and govern memory formation. We conclude that this experimental demonstration of rudimentary stimulus-response patterns represents a first step toward a study of minimal cognition in bioengineered 3D neural tissues. Next steps are discussed with an emphasis on current challenges and limitations to in vivo approaches in the cognitive sciences.

A facet theory approach for the psychometric measurement of conflict monitoring

We investigated psychometric parameters and the factorial validity of a newly developed conflict monitoring questionnaire (CMQ). Whereas the integrative conflict monitoring theory presumes that higher cognitive demand serves as a teaching signal that intensifies conflict monitoring, the revised reinforcement sensitivity theory predicts that more anxious individuals anticipate more negative consequences because of a more active behavioral inhibition system (BIS). Experimental paradigms on conflict and performance monitoring reveal that the determinants of conflict monitoring imply response patterns (e.g., response adaptation or decisions under uncertainty). Since information processing can be conceived as a combination of stimulus monitoring and response patterns, each item of the CMQ comprises a determinant and a response pattern in accordance with facet theory. A total of N = 666 participants (284 male) filled in the CMQ. We performed a bifactor multiple-indicator-multiple-cause (MIMIC) model to investigate the factorial structure and measurement equivalence for gender and place of research. Our data support a four-factor model with two latent factors demonstrating determinants of conflict monitoring and two latent factors revealing response patterns of conflict monitoring. Moreover, a general performance monitoring factor was confirmed. Measurement equivalence of the latent factors was tested for gender and place of research.

On the Generalization of Habituation: How Discrete Biological Systems Respond to Repetitive Stimuli

Habituation, a form of non-associative learning, isno longer studied exclusively within the fields of psychology and neuroscience. Indeed, the same stimulus-response pattern is observed at the molecular, cellular, and organismal scales and is not dependent upon the presence of neurons. Hence, a more inclusive theory is required to accommodate aneural forms of habituation. Here an abstraction of the habituation process that does not rely upon particular biological pathways or substrates is presented. Instead, five generalizable elements that define the habituation process are operationalized. The formulation can be applied to interrogate systems as they respond to several stimulation paradigms, providing new insights and supporting existing behavioral data. The model can be used to deduce the relative contribution of elements that contribute to the measurable output of the system. The results suggest that habituation serves as a general biological strategy that any system can implement to adaptively respond to harmless, repetitive stimuli.

Components in the P300: Don't forget the Novelty P3!

This study investigated stimulus-response patterns of temporal principal components analysis (PCA)-derived event-related potential (ERP) components in a classical auditory habituation paradigm with long interstimulus intervals. The skin conductance response (SCR) was included as the "gold standard" model of the Orienting Reflex. Thirty participants were presented with a single series of 10 identical 60dB tones, followed by a change trial at a different frequency. Single-trial, electrooculography-corrected ERPs were submitted to temporal PCA. The main focus was on the components expected in the P300/Late Positive Complex (LPC), and their electromagnetic tomography-derived cortical sources. Nine components were identified between 90 and 470ms poststimulus (in temporal order): three N1 subcomponents, P2, four LPC components, and a negative Slow Wave (SW). The expected order of P3a, P3b, Novelty P3 (nP3), and positive Slow Wave (+SW) in the LPC was confirmed. SCR demonstrated strong exponential decay and recovery. P3b and nP3 each showed exponential decrement over trials, but only nP3 showed recovery at the change trial. Novelty effects failed to reach significance for the other LPC components, and were not apparent in non-LPC components. Frontal lobe activity in Brodmann areas 6, 8, and 9 was common to P3a, P3b, nP3, and+SW, consistent with the functional integration of these components in the LPC. Individual components had specific sources, although some sources overlapped between components or were reactivated later in the LPC. These data provide a fresh perspective on the components of the LPC and their cortical sources, and offer a processing model for the P300 in a habituation task, potentially generalizable to other paradigms.

Right cerebral hemispheric sensitivity to pH and physiological ions in fixed post-mortem Wistar rat brains

Post-mortem human neural tissues fixed in ethanol and aldehyde-based solutions express modulated frequency-dependent microvolt potentials when probed by chemical and electrical stimuli. These observations run contrary to the assumption that basic tissue functions are irreversibly impaired upon fixation, in the absence of nutrients and sufficient concentrations of physiological ions. The aim of the current study was to investigate the relative effects of pH and specific charged particles relevant to normal cell physiology upon electric potentials associated with fixed post-mortem rat brain tissue. We identified a positive relationship between the total time the brains had been immersed in ethanol-formalin-acetic acid and high-frequency microvolt potentials within the dorsal right hemisphere of the rat cerebrum. Measuring the pH of the fixative solution surrounding the brains indicated that as time increased, a logarithmic trend toward alkalinity could be observed. Further experiments revealed that high-frequency microvolt potentials were related to pH changes within the right hemisphere only. The right ventral cerebrum displayed a unique response to potassium chloride in ways uncounted for by pH alone. The results suggest that the fixed post-mortem right cerebrum of the rat is particularly sensitive to pH and physiological ions which explains a subset of previous findings with respect to stimulus-response patterns in human coronal brain sections. A concluding hypothesis is presented which suggests that brain tissue expresses material properties independent of metabolic activity though perhaps relevant to living brain function.

Significance and Novelty effects in single-trial ERP components and autonomic responses

The phasic orienting reflex (OR) was investigated in two counterbalanced blocks of an auditory dishabituation paradigm differing in stimulus Significance (operationalised as tone counting). Twelve tones were presented at very long, randomly-varying interstimulus intervals (ISIs). Novelty and Significance were varied within subjects. Stimulus-response patterns were assessed to find ERP matches for autonomic measures. The phasic OR index was represented by the skin conductance response (SCR). SCR decremented over 10 standard trials, showed recovery on trial 11 (change trial), enhancement to re-presentation of the standard tone (trial 12: dishabituation), and a main effect of Significance over the first 10 trials – demonstrating the formal criteria for an OR index. The evoked cardiac response (HR) subcomponents ECR1 (deceleration) and ECR2 (acceleration) showed no trial effects, but ECR2 showed a Significance effect. Respiratory pause (RP) decreased linearly over trials, and showed recovery, but no dishabituation or Significance effect. Temporal PCA was applied to single-trial EOG-corrected data. Ten ERP components were extracted: P1, N1-3, N1-1, PN, P2, P3a, P3b, HabP3, a Frontal Slow Wave (FSW), and the Classic SW. The dependent measures showed 4 distinct patterns. Pattern 1: No trial or Significance effects (ECR1, P1, N1-3, P3a, FSW); Pattern 2: No trial effect but a Significance effect (ECR2, N1-1, P2); Pattern 3: Trial but not Significance effects (RP, PN, P3b, HabP3); Pattern 4: Both trial and Significance effects (SCR and Classic SW). The evidenced fractionation of autonomic and central measures is compatible with Preliminary Process Theory (PPT), contrary to the notion of a unitary OR.

Control Techniques for Synchronizing the States of Two Coupled Van der Pol Oscillators

Mathematical models of nonlinear oscillators are used to describe a wide variety of physical and biological phenomena that exhibit self-sustained oscillatory behavior. When these oscillators are strongly driven by forces that are periodic in time, they often exhibit a remarkable ‘‘mode-locking’’ that synchronizes the nonlinear oscillations to the driving force. Oscillation is the repetitive variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states and is characterized by their amplitude and their phase. Their interactions can result in a systematic process of synchronization which is the adjustment of rhythms of oscillating objects due to an interaction and is quite distinct from a simple stimulus response pattern. Oscillators respond to stimuli at some times in their cycle and may not respond at others. Many important physical, chemical and biological systems are composed of coupled nonlinear oscillators. The Van der Pol equation has been used to model a number of biological processes such as the heartbeat, circadian rhythms, biochemical oscillators, and pacemaker neurons. Two such resistively coupled Van der Pol oscillators are analyzed and the phenomenon of synchronization between the states of the coupled oscillators is explored. Several control techniques to achieve synchronization are designed, implemented and performance evaluation carried out by simulation using MATLAB Software.

Distinct Somatic Discrimination Reflected by Laser-Evoked Potentials Using Scalp EEG Leads.

Discrimination is an important function in pain processing of the somatic cortex. The involvement of the somatic cortex has been studied using equivalent dipole analysis and neuroimaging, but the results are inconsistent. Scalp electroencephalography (EEG) can reflect functional changes of particular brain regions underneath a lead. However, the responses of EEG leads close to the somatic cortex in response to pain have not been systematically evaluated. The present study applied CO2 laser stimulation to the dorsum of the left hand. Laser-evoked potentials (LEPs) of C4, T3, and T4 leads and pain ratings in response to four stimulus intensities were analyzed. LEPs started earlier at the C4 and T4 leads. The onset latency and peak latency of LEPs for C4 and T4 leads were the same. Only 10 of 22 subjects (45 %) presented equivalent current dipoles within the primary somatosensory or motor cortices. LEP amplitudes of these leads increased as stimulation intensity increased. The stimulus–response pattern of the C4 lead was highly correlated with pain rating. In contrast, an S-shaped stimulus–response curve was obtained for the T3 and T4 leads. The present study provides supporting evidence that particular scalp channels are able to reflect the functional characteristics of their underlying cortical areas. Our data strengthen the clinical application of somatic-cortex-related leads for pain discrimination.

A Simplified Car-following Model Based on the Artificial Potential Field

Car-following models, which describe the interaction between successive vehicles in the same lane, have been studied for decades. A group of models are derived from the stimulus-response pattern concentrating on the effect of diverse stimulus type. This study presents a potential-based car-following model using the concept of the artificial potential field, which aims for the precise and fast interactive operations in an evolving environment. Spacing headway is divided into two parts according to the potential influence region. The variation rate of the spacing headway generates the control force within the potential influence region, while the difference of desired and current velocity takes control out of the influence range. Calibration and validation of the simplified model are conducted using NGSIM data. Statistical tests show that the proposed model can reproduce the car-following process very well.

Trials and intensity effects in single-trial ERP components and autonomic responses in a dishabituation paradigm with very long ISIs

The phasic orienting reflex (OR) was investigated using single-trial data collected concurrently from 4 autonomic measures and event-related potentials (ERPs). In an auditory dishabituation paradigm, twelve indifferent tones of two intensities (60 or 80dB, intensity change on trial 11, counterbalanced between subjects) were presented at very long interstimulus intervals (ISIs). Novelty and intensity based stimulus–response patterns were examined seeking ERP analogues of autonomic measures representing pre-OR and OR processing. Skin conductance response (SCR) represented the phasic OR index. EOG-corrected ERP data for 16 subjects were decomposed by a temporal Principal Components Analysis (PCA). SCR diminished over 10 standard trials, recovered on change trial 11, dishabituated to the re-presentation of the standard tone on trial 12, and showed intensity effects at the change — formal requirements for an OR index. The evoked cardiac response (HR) showed no trial or intensity effects. Respiratory pause (RP) decreased linearly over trials and showed recovery but no dishabituation or intensity effect. Peripheral vasoconstriction (PVC) failed to decrement but exhibited an intensity effect. Ten identifiable ERP components were extracted: Na, P1, N1-1, PN, P2, P3a, P3b, a novelty-sensitive HabP3, an intensity-sensitive IntP3, and the Slow Wave (SW). Pattern 1 showed no trial or intensity effects (HR, P1, PN, P2); Pattern 2 showed no trial effect but an intensity effect (PVC, Na, N1-1, P3a); and Pattern 3 demonstrated habituation and an intensity effect (SCR, RP, P3b, HabP3, IntP3, SW). The observed fractionation of autonomic and central measures is consistent with Preliminary Process Theory (PPT) rather than the notion of a unitary OR.

Neuroscience Implications of Using Hypnoanalysis: Two Case Studies

Abstract Neuroscience is providing growing evidence that psychopathology is related to neural integration and amygdala-based implicit memories. Understanding the brain provides psychotherapists a guide for treatment, and neuroscience points to hypnosis as a potent treatment tool. Hypnosis affects functional areas of the brain, including the amygdaloid memory system and neural integration. Hypnosis in itself is not curative. Neuroscience, more recent psychotherapy models, and modern understandings of hypnoanalysis appear to confirm Freud’s early observations of hypnosis effectiveness and, for his objection that hypnosis works well for some clients but not for others, explain why. Neuroscience’s understanding of the development of psychopathology and psychotherapy models give us tools and models Freud did not have. Using age regression (abreaction) in hypnosis in the context of psychotherapy appear to provide direct access to amygdala-based implicit memories during which the content of implicit memories can be explored for the unconscious meaning and for the responses conditioned during traumatic events. With the skilled use of psychotherapy treatment models while a client is in hypnosis, new patterns can be created through neurologically vividly experiences. These vivid experiences create new, reconditioned patterns that appear to reflect direct changes in the amygdala-based implicit memories and neural integration, evidenced by clients’new, automatic responses in previously difficult circumstances. Two case studies illustrate the use of Ego Psychology, Self Psychology, Attachment and Narrative psychotherapy models during hypnotic age regressions to disconnect stimulus-response patterns in a phobia client and provide vivid experiences of attachment and guidance for a borderline client.

Beyond nociception

It seemsthat despite extensive advances in multiple fields,we have made little ground. In this topical review, we put forwardanewhypothesisofchronicpainthatexplainsthemostcommonpainful disorders, such as chronic widespread pain, nonspecificback or neck pain, and fibromyalgia. Our hypothesis draws onalonghistoryoffundamentalresearchinassociativelearningandis based on 2 core assumptions (1) that pain can be considereda response, not just a stimulus, and (2) that encoding non-nociceptive information predictably coincident with nociceptiveinput underpins the response to subsequent similar events.Briefly, our hypothesis posits that the precision with whichmultisensoryinformation(temporal,proprioceptive,spatial)aboutthe painful event is encoded and represented in the brain willdetermine the degree to which the painful response willsubsequently generalize to similar events.Much of the literature on pain considers it analogous tonociception, activity in high-threshold afferent neurons and theircentral projections. However, a very large body of evidencedemonstrates that nociception is neither sufficient nor necessaryfor pain (see Refs. 4,11,22). Pain is now considered a consciousexperiencethatcanbe,andoftenis,associatedwithnociception,but it is always modulated by a myriad of neurobiological,environmental, and cognitive factors. Plasticity, or the alterationsin stimulus–response patterns that occur over time, is thought tobeimportantinchronicpainandcanoccurinatleast2ways.Oneis nonassociative when the organism’s response to a stimuluschanges by virtue of repeated exposure to that particularstimulus. Habituation is 1 example of nonassociative plasticity,such that the response to a given stimulus decreases.Sensitization is another example, such that the response toa given stimulus increases. Sensitization of spinal nociceptors isconsidered a key mechanism underpinning persistent pain afterprimary nerve trauma or dysfunction; repeated noxious stimula-tion leads to a shift in the stimulus–response pattern of the spinalnociceptor.Asecondarguablymorecomplexformofplasticityinvolvestheassociation of at least 2 stimuli, such is the typical case ofclassical (Pavlovian) conditioning or associative learning.

Intensity and Trial Effects for Simple Auditory Stimuli in a Dishabituation Paradigm

Event Abstract Back to Event Intensity and Trial Effects for Simple Auditory Stimuli in a Dishabituation Paradigm Brett Macdonald1* and Robert J. Barry1 1 university of wollongong, Australia Aim We examined the influence of novelty and intensity in the rarely used auditory dishabituation paradigm. Stimulus-response (S-R) patterns were examined for autonomic and central measures and quantitatively compared to the phasic skin conductance response (SCR) –the OR benchmark. Differing patterns consistent with Preliminary Process Theory (PPT) were sought. Method Sixteen undergraduates experienced twelve 1000 Hz tones (60/80 dB, 50 ms with 15 ms rise/fall times) presented with random ISIs (45 to 70 s), and no task requirements. Subjects were counterbalanced according to the starting tone intensity. The first 10 standard trials were of one intensity, followed by a change trial at the other intensity (recovery), and a subsequent dishabituation trial at the initial tone. The SCR, Evoked Cardiac Response(ECR), Respiratory Pause (RP), Peripheral Vasoconstriction (PVC), and single-trial ERPs from 19 sites, were collected. EOG-corrected ERP data were submitted to a temporal Principle Components Analysis (PCA). Novelty was assessed via trial decrement, and intensity via the group × trials interaction at recovery. Results SCR displayed decrement, recovery (trials and group × trials), and dishabituation. Three S-R patterns emerged based on the SCR S-R pattern, correlation analysis, and temporal PCA groupings. Pattern 1 (novelty and intensity insensitivity): HR, P1, PN, and P2. Pattern 2 (no decrement but intensity sensitivity): PVC, Na, N1-1, and P3a. Pattern 3 (novelty and intensity sensitivity): SCR, RP, P3b, HabP3, IntP3, and SW. Conclusions The S-R patterns of the autonomic measures were generally consistent with previous findings. Each pattern contained both autonomic and ERP measures. Various ERP components failed to differ from the hallmark S-R pattern of the OR. Fractionation of responses was found for both autonomic and central measures, and their patterns were consistent with PPT. References Barry, R. J. (1984). Preliminary Processes in O-R Elicitation. Acta Psychol., 55, 109-142. Barry, R. J. (1996). Preliminary process theory: Towards an integrated account of the psychophysiology of cognitive processes. Acta Neurobiol. Exp. (War), 56, 469-484. Sokolov, E. N. (1963). Perception and the conditioned reflex. Pergamon, Oxford. Keywords: orienting reflex, Preliminary process theory, dishabituation, Principle components analysis, Intensity Conference: ASP2015 - 25th Annual Conference of the Australasian Society for Psychophysiology, Sydney, Australia, 2 Dec - 4 Dec, 2015. Presentation Type: Poster Presentation Topic: Psychophysiology Citation: Macdonald B and Barry RJ (2015). Intensity and Trial Effects for Simple Auditory Stimuli in a Dishabituation Paradigm. Conference Abstract: ASP2015 - 25th Annual Conference of the Australasian Society for Psychophysiology. doi: 10.3389/conf.fnhum.2015.219.00034 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 22 Oct 2015; Published Online: 30 Nov 2015. * Correspondence: Mr. Brett Macdonald, university of wollongong, wollongong, Australia, brettell08@yahoo.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Brett Macdonald Robert J Barry Google Brett Macdonald Robert J Barry Google Scholar Brett Macdonald Robert J Barry PubMed Brett Macdonald Robert J Barry Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Trial effects in single-trial ERP components and autonomic responses at very long ISIs

Single-trial data from autonomic and ERP measures were used to capture the rapidly decreasing initial responses characteristic of the orienting reflex (OR) to repeated stimuli. Stimulus–response patterns were compared to determine central analogues of autonomic indices of processes leading to the OR, and the OR itself. Participants were presented with 12 indifferent tones in an auditory dishabituation paradigm. Temporal principal component analysis (PCA) decomposed EOG-corrected ERP data for 16 subjects. Response patterns of ERPs, cardiac, and respiratory responses were compared to the phasic skin conductance response (SCR). SCR decremented over trials, recovered on the change trial, and dishabituated to the representation of the standard, meeting the formal definition of habituation required of the OR. The evoked cardiac response showed no trial effects. Respiratory pause (RP) decreased linearly over trials, recovering marginally on the change trial. Nine identifiable ERP components were extracted: P1, N1-3, N1-1, processing negativity (PN), P2, P3a, P3b, a novelty-sensitive P3 component (labelled HabP3), and the slow wave (SW). P3b and SW showed decrement over trials, but with no recovery, HabP3 showed decrement and increased response on the change trial, while the P1, N1 subcomponents, P2 and P3a were insensitive to novelty. Stimulus–response patterns of the RP and HabP3 suggest sensitivity to novelty processing, while the P1, N1-3, N-1, PN, P2, P3a and cardiac deceleration appear to mark processing prior to novelty, such as stimulus transient detection (cardiac deceleration) and/or intensity processing. This study supports predictions of preliminary process theory, demonstrating fractionation of 3 autonomic and 9 ERP components to novelty, and disconfirming the unitary nature of the OR.