Intramodal and crossmodal refractory effects: Evidence from oscillatory brain activity

2012 ◽  
Vol 25 (0) ◽  
pp. 192
Author(s):  
Davide Bottari ◽  
Sophie Rohlf ◽  
Marlene Hense ◽  
Boukje Habets ◽  
Brigitte Roeder

Event-related potentials (ERP) to the second stimulus of a pair are known to be reduced in amplitude. The magnitude of this ‘refractoriness’ is modulated by both the interstimulus interval and the similarity between the two stimuli. Intramodal refractoriness is interpreted as an index of a temporary decrement in neural responsiveness. So, cross-modal refractoriness might be an indicator of shared neural generators between modalities. We analysed oscillatory neuronal activity while participants were engaged in an oddball paradigm with auditory (4000 Hz, 50 ms-long, 90 db, bilateral) and tactile stimuli (50 ms-long, 125 Hz-vibrations, index fingers) presented in a random order with an ISI of either 1000 or 2000 ms. Participants were required to detect rare tactile (middle fingers) and auditory deviants (600 Hz). A time–frequency analysis of the brain response to the second stimulus of each pair (T-T, A-A, T-A and A-T) contrasting Short and Long ISIs revealed a reduced refractory effect after Long ISI with respect to Short ISI, in all pairs (both intramodal and cross-modal). This emerged as a broadly distributed increase of evoked theta activity (3–7 Hz, 100–500 ms). Only in intramodal tactile pairs and cross-modal tactile-auditory pairs we also observed that Long ISI with respect to Short ISI determined a decrease of induced alpha (8–12 Hz, 200–700 ms), a typical sign of enhanced neural excitability and thus decreased refractoriness. These data suggest that somatosensory and auditory cortices display different neural markers of refractoriness and that the auditory cortex might have a stronger low level degree of influence on the tactile cortex than vice-versa.

2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
M. Constante ◽  
M. Shaikh ◽  
I. Williams ◽  
R. Murray ◽  
E. Bramon

Objective:Abnormalities in event related potentials (ERPs) have long been looked at as markers of disease in Schizophrenia. Over recent years there is a trend in the field to move from averaged trials ERPs analysis in the time-voltage domain, to time-frequency single trials analysis. Oscillations in the Gamma band (30-50Hz) have received particular attention in the context of the theories of core deficits in neuronal synchronization in Schizophrenia. in this study we aimed at replicating previously found Gamma band deficits in a sample of Early Psychosis patients.Methods:EEG was collected from 15 patients and 15 age matched controls using an auditory oddball paradigm. Time-frequency analysis in the Gamma band was performed using a Morlet wavelet transform. We tested differences between the groups using the Wilcoxon rank sum test, given the nonparametric nature of the data, to compare each group's average single trial Gamma power, maximizing the signal-to-noise ratio.Results:Patients with Early Psychosis showed, following target tones, a reduction in the total power of Gamma band activation (p< 0.01) as well as in induced Gamma band activation (p< 0.01). This was observed in a late latency interval at 400-500ms. the late burst of Gamma activity was not found in the frequent condition, for neither subjects group.Conclusion:The findings are compatible with previous studies suggesting deficits in the late intrinsically generated cognitive processing of auditory stimuli in Schizophrenia, already present in its early stage. They add further evidence of deficits in neuronal synchronisation in the early stages of psychotic disorders.


2013 ◽  
Vol 479-480 ◽  
pp. 480-485
Author(s):  
Ming Chung Ho ◽  
Chin Fei Huang ◽  
Chia Yi Chou ◽  
Ming Chi Lu ◽  
Chen Hsieh ◽  
...  

Brain dynamics is an important issue in understanding child development. However, very little research of the event-related responses has been used to explore changes during childhood. The aim of this study was to investigate mature changes in spatiotemporal organization of brain dynamics. We hypothesized that oscillatory event-related brain activity were affected by age-related changes. The sample include three age groups, namely 7 years (N = 18), 11 years (N = 18), and adults (N = 18). The event-related spectral power (ERPSP), and inter-trial phase locking (ITPL) of the event-related potentials (ERPs) were obtained from the time-frequency analysis of the auditory oddball task. Results revealed that: (a) decreased theta power, but alpha power increased with age; (b) the values of ITPL in the theta and alpha bands increased with age. These suggest that ERPSP, and ITPL provide useful indicators of cognitive maturation processes in children aged 7 and 11 years.


2018 ◽  
Author(s):  
Yuri G. Pavlov ◽  
Boris Kotchoubey

AbstractThe nature of cortical plasticity in the course of learning is one of the most intriguing questions of the modern cognitive neuroscience. Aversive conditioning is a type of associative learning produced by continuous pairing of neutral and aversive stimuli. Aversive conditioning and electroencephalography together provide a good framework for expanding our knowledge about fast learning-related cortical changes. In our experiment we tested a novel paradigm to study associative learning where aversive conditioning was combined with passive oddball. We employed conditioned auditory neutral stimuli and unconditioned aversive electrical shocks and used time-frequency, connectivity and event-related potentials (ERP) analyses to explore their interaction. First, we observed changes in the cortical activity in the form of conditioning-induced multisensory integration. The integration manifested itself in (1) desynchronization of lower beta activity in the contralateral to expected electrical shocks hemisphere and (2) enhanced functional connectivity between auditory and somatosensory cortex in the gamma frequency band. Second, we found a larger amplitude of P3a and the late posterior positivity (LPP) components of ERP to conditioned stimuli, which may be related to increased attentional and emotional significance of these stimuli. Our results reproduced and extended previous findings about multisensory integration in classical conditioning and demonstrated the improved discriminability of ERP responses through incorporation of the oddball paradigm in associative learning.


PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0257380
Author(s):  
Marcel Franz ◽  
Barbara Schmidt ◽  
Holger Hecht ◽  
Ewald Naumann ◽  
Wolfgang H. R. Miltner

Several theories of hypnosis assume that responses to hypnotic suggestions are implemented through top-down modulations via a frontoparietal network that is involved in monitoring and cognitive control. The current study addressed this issue re-analyzing previously published event-related-potentials (ERP) (N1, P2, and P3b amplitudes) and combined it with source reconstruction and connectivity analysis methods. ERP data were obtained from participants engaged in a visual oddball paradigm composed of target, standard, and distractor stimuli during a hypnosis (HYP) and a control (CON) condition. In both conditions, participants were asked to count the rare targets presented on a video screen. During HYP participants received suggestions that a wooden board in front of their eyes would obstruct their view of the screen. The results showed that participants’ counting accuracy was significantly impaired during HYP compared to CON. ERP components in the N1 and P2 window revealed no amplitude differences between CON and HYP at sensor-level. In contrast, P3b amplitudes in response to target stimuli were significantly reduced during HYP compared to CON. Source analysis of the P3b amplitudes in response to targets indicated that HYP was associated with reduced source activities in occipital and parietal brain areas related to stimulus categorization and attention. We further explored how these brain sources interacted by computing time-frequency effective connectivity between electrodes that best represented frontal, parietal, and occipital sources. This analysis revealed reduced directed information flow from parietal attentional to frontal executive sources during processing of target stimuli. These results provide preliminary evidence that hypnotic suggestions of a visual blockade are associated with a disruption of the coupling within the frontoparietal network implicated in top-down control.


2021 ◽  
Author(s):  
Santiago Morales ◽  
Maureen Bowers

EEG provides a rich measure of brain activity that can be characterized as neuronal oscillations. However, most developmental EEG work to date has focused on analyzing EEG data as Event-Related Potentials (ERPs) or power based on the Fourier transform. While these measures have been productive, they do not leverage all the information contained within the EEG signal. Namely, ERP analyses ignore non-phase-locked signals and Fourier-based power analyses ignore temporal information. Time-frequency analyses can better characterize the oscillations contained in the EEG data. By separating power and phase information across different frequencies, time-frequency measures provide a closer interpretation of the neurophysiological mechanisms, facilitate translation across neurophysiology disciplines, and capture processes not observed by ERP or Fourier-based analyses (e.g., connectivity). Despite their unique contributions, a literature review of this journal reveals that time-frequency analyses of EEG are yet to be embraced by the developmental cognitive neuroscience field. This manuscript presents a conceptual introduction to time-frequency analyses for developmental researchers. To facilitate the use of time-frequency analyses, we include a tutorial of accessible scripts, based on Cohen (2014), to calculate time-frequency power (signal strength), inter-trial phase synchrony (signal consistency), and two types of phase-based connectivity (inter-channel phase synchrony and weighted phase lag index).


2009 ◽  
Vol 23 (4) ◽  
pp. 157-173 ◽  
Author(s):  
Robert J. Barry ◽  
Adam R. Clarke

Data are presented on EEG activity in typically developing controls, focusing on the traditional delta, theta, alpha, and beta bands through childhood, with some extensions into adolescence and adults. Both eyes-closed and eyes-open resting state data are discussed. These reflections of typical development provide a framework for illustrating EEG differences in people with attention deficit/hyperactivity disorder (AD/HD), and its main diagnostic types, from children to adults. Comorbidity effects in the EEG of children with AD/HD, particularly comorbid reading disabilities and conduct disorders, are also described. Some recent explorations of the links between arousal/activation and EEG activity may contribute to our understanding of the functional nature of brain oscillations in this context. Other aspects of oscillatory brain activity, coherence and event-related potentials, are also briefly discussed within this framework.


2017 ◽  
Vol 31 (7) ◽  
pp. 873-882 ◽  
Author(s):  
Eduardo López-Caneda ◽  
Socorro Rodríguez Holguín ◽  
Ángeles Correas ◽  
Carina Carbia ◽  
Alberto González-Villar ◽  
...  

Introduction: Neurofunctional studies have shown that binge drinking patterns of alcohol consumption during adolescence and youth are associated with anomalies in brain functioning. Recent evidence suggests that event-related oscillations may be an appropriate index of neurofunctional damage associated with alcoholism. However, there is no study to date that has evaluated the effects of binge drinking on oscillatory brain responses related to task performance. The purpose of the present study was to examine brain oscillations linked to motor inhibition and execution in young binge drinkers (BDs) compared with age-matched controls. Methods: Electroencephalographic activity was recorded from 64 electrodes while 72 university students (36 controls and 36 BDs) performed a visual Go/NoGo task. Event-related oscillations along with the Go-P3 and NoGo-P3 event-related potential components were analysed. Results: While no significant differences between groups were observed regarding event-related potentials, event-related oscillation analysis showed that BDs displayed a lower oscillatory response than controls in delta and theta frequency ranges during Go and NoGo conditions. Conclusions: Findings are congruent with event-related oscillation studies showing reduced delta and/or theta oscillations in alcoholics during Go/NoGo tasks. Thus, BDs appear to show disruptions in neural oscillations linked to motor inhibition and execution similar to those observed in alcohol-dependent subjects. Finally, these results are the first to evidence that oscillatory brain activity may be a sensitive indicator of underlying brain anomalies in young BDs, which could complement standard event-related potential measures.


2005 ◽  
Vol 17 (7) ◽  
pp. 1098-1114 ◽  
Author(s):  
Durk Talsma ◽  
Marty G. Woldorff

We used event-related potentials (ERPs) to evaluate the role of attention in the integration of visual and auditory features of multisensory objects. This was done by contrasting the ERPs to multisensory stimuli (AV) to the sum of the ERPs to the corresponding auditory-only (A) and visual-only (V) stimuli [i.e., AV vs. (A + V)]. V, A, and VA stimuli were presented in random order to the left and right hemispaces. Subjects attended to a designated side to detect infrequent target stimuli in either modality there. The focus of this report is on the ERPs to the standard (i.e., nontarget) stimuli. We used rapid variable stimulus onset asynchronies (350-650 msec) to mitigate anticipatory activity and included “no-stim” trials to estimate and remove ERP overlap from residual anticipatory processes and from adjacent stimuli in the sequence. Spatial attention effects on the processing of the unisensory stimuli consisted of a modulation of visual P1 and N1 components (at 90-130 msec and 160-200 msec, respectively) and of the auditory N1 and processing negativity (100-200 msec). Attended versus unattended multisensory ERPs elicited a combination of these effects. Multisensory integration effects consisted of an initial frontal positivity around 100 msec that was larger for attended stimuli. This was followed by three phases of centro-medially distributed effects of integration and/or attention beginning at around 160 msec, and peaking at 190 (scalp positivity), 250 (negativity), and 300-500 msec (positivity) after stimulus onset. These integration effects were larger in amplitude for attended than for unattended stimuli, providing neural evidence that attention can modulate multisensory-integration processes at multiple stages.


Sign in / Sign up

Export Citation Format

Share Document