scholarly journals The Effect of Task on Object Processing revealed by EEG decoding

2020 ◽  
Author(s):  
Hoi Ming Ken Yip ◽  
Leo Y. T. Cheung ◽  
Yetta Kwailing Wong ◽  
Alan C.-N. Wong
Keyword(s):  
Temporal Resolution ◽  
Real Life ◽  
Task Demands ◽  
Event Related Potential ◽  
Task Demand ◽  
Time Range ◽  
Late Time ◽  
Object Representations ◽  
Object Processing ◽  
Multivariate Pattern

AbstractAt which phase(s) does task demand affect object processing? Previous studies showed that task demand affects object representations in higher-level visual areas but not so much in earlier areas. There are, however, limitations in those studies concerning the relatively weak manipulation of task due to the use of familiar real-life objects, and/or the low temporal resolution in brain activation measures such as fMRI. In the current study, observers categorized images of artificial objects in one of two orthogonal dimensions, shape and texture. Electroencephalogram (EEG), a technique with higher temporal resolution, and multivariate pattern analysis (MVPA) were employed to reveal object processing across time under different task demands. Results showed that object processing along the task-relevant dimension was enhanced starting from a relatively late time (∼230ms after image onset), within the time range of the event-related potential (ERP) components N170 and N250. The findings are consistent with the view that task exerts an effect on object processing at the later phases of processing in the ventral visual pathway.

scholarly journals Sequential Congruency Effects of Reverse Stroop Interference on Event-Related Potential Components for Go- and Nogo-Stimuli

2021 ◽  
Vol 12 ◽  
Author(s):  
Kota Suzuki
Keyword(s):  
Cognitive Control ◽  
Response Inhibition ◽  
Attentional Control ◽  
Reaction Times ◽  
Event Related Potential ◽  
The Other ◽  
Task Demand ◽  
Time Range ◽  
Color Processing ◽  
Sequential Modulation

Sequential congruency effects are observed in interference tasks, in which reaction times (RTs) are shorter for congruent stimuli preceded by congruent (cC) than incongruent stimuli (iC), and RTs are longer for incongruent stimuli preceded by congruent (cI) than incongruent stimuli (iI). These effects are interpreted as resulting from incongruent stimuli triggering attentional control in the next trial, which reduces cognitive control. This study aimed to examine sequential congruency effects on event-related potential (ERP) components for Go- and Nogo-stimuli. We used the hybrid reverse Stroop Go/Nogo task. The stimuli were Kanji characters, “赤” (i.e., red) and “青” (i.e., blue) painted in congruent and incongruent colors. Participants responded to one of the two characters (i.e, the Go-stimulus) and stopped responding to the other character (i.e., the Nogo-stimulus). The results indicated that the Nogo-N1 was reduced by trials preceded by incongruent stimuli compared with congruent ones, suggesting that color processing was inhibited by attentional control; however, there was no reduction in the Go-N1. In addition, the Nogo-N2 amplitudes were larger for cI than iI and iC than cC. On the other hand, the Go-N2 was not modulated by sequential modulation effects, which was lower for incongruent stimuli than congruent stimuli. These results indicate that the Nogo-N2 is involved in cognitive control, whereas the Go-N2 is associated with selection processing. These findings suggest that the modulation of sequential congruency effects of N1 and N2 required the response inhibition task demand; however, Go-P3 and Nogo-P3 amplitudes were the largest for cI. Therefore, the time range of ERP components might be related to the susceptibility of an interaction effect between response inhibition task demand and sequential congruency effects.

scholarly journals Event-related potential signatures of perceived and imagined emotional and food real-life photos

2015 ◽  
Vol 31 (3) ◽  
pp. 317-330 ◽  
Author(s):  
Fernando Marmolejo-Ramos ◽  
Kim Hellemans ◽  
Amy Comeau ◽  
Adam Heenan ◽  
Andrew Faulkner ◽  
...  
Keyword(s):  
Real Life ◽  
Event Related Potential

scholarly journals Electrophysiological evidence of different neural processing between visual and audiovisual inhibition of return

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiaoyu Tang ◽  
Xueli Wang ◽  
Xing Peng ◽  
Qi Li ◽  
Chi Zhang ◽  
...  
Keyword(s):  
Multisensory Integration ◽  
Temporal Resolution ◽  
Inhibition Of Return ◽  
Neural Correlates ◽  
Event Related Potential ◽  
Perceptual Processing ◽  
High Temporal Resolution ◽  
Neural Processing ◽  
Electrophysiological Evidence ◽  
P3 Component

AbstractInhibition of return (IOR) refers to the slower response to targets appearing on the same side as the cue (valid locations) than to targets appearing on the opposite side as the cue (invalid locations). Previous behaviour studies have found that the visual IOR is larger than the audiovisual IOR when focusing on both visual and auditory modalities. Utilising the high temporal resolution of the event-related potential (ERP) technique we explored the possible neural correlates with the behaviour IOR difference between visual and audiovisual targets. The behavioural results revealed that the visual IOR was larger than the audiovisual IOR. The ERP results showed that the visual IOR effect was generated from the P1 and N2 components, while the audiovisual IOR effect was derived only from the P3 component. Multisensory integration (MSI) of audiovisual targets occurred on the P1, N1 and P3 components, which may offset the reduced perceptual processing due to audiovisual IOR. The results of early and late differences in the neural processing of the visual IOR and audiovisual IOR imply that the two target types may have different inhibitory orientation mechanisms.

An Electrophysiological Measure of Temporal Resolution in Normal Subjects Using Frequency Modulated Signals

2002 ◽  
Vol 11 (1) ◽  
pp. 42-49
Author(s):  
Devin L. McCaslin ◽  
Lawrence L. Feth ◽  
Gary P. Jacobson ◽  
Pamela J. Mishler
Keyword(s):  
Temporal Resolution ◽  
Mismatch Negativity ◽  
Normal Subjects ◽  
Single Step ◽  
Event Related Potential ◽  
Frequency Range ◽  
Temporal Properties ◽  
Step Duration ◽  
The Mean ◽  
Modulated Signals

This investigation was conducted to determine whether an exogenous event-related potential called the mismatch negativity (MMN) would change systematically in response to frequency-modulated signals with varying temporal properties. Both N1 and P2 waveforms were recorded for 50-ms frequency-modulated signals from normal hearing listeners. The standard stimuli for this investigation were continuous sweep tones with center frequencies of 1000 Hz that traversed a frequency range of 200 Hz in a single step. The rare stimuli were signals that traversed the same frequency range in two, four, six, or eight discrete steps. Results suggest that for the 10 participants, 1) the mean MMN peak-to-peak amplitude and mean area decreased significantly with decreases in step duration, 2) MMN area amplitude was the best indicator of psychophysical performance for the two magnitude measures, and 3) MMN onsets and peak latencies did not show either a significant increase or decrease in latency as step duration decreased.

To Predict or Not to Predict: Influences of Task and Strategy on the Processing of Semantic Relations

2007 ◽  
Vol 19 (8) ◽  
pp. 1259-1274 ◽  
Author(s):  
Dietmar Roehm ◽  
Ina Bornkessel-Schlesewsky ◽  
Frank Rösler ◽  
Matthias Schlesewsky
Keyword(s):  
Semantic Relatedness ◽  
Presentation Mode ◽  
Judgment Task ◽  
Sentence Context ◽  
Task Demands ◽  
Event Related Potential ◽  
Semantic Relations ◽  
Decision Task ◽  
Lexical Semantic ◽  
Experimental Environment

We report a series of event-related potential experiments designed to dissociate the functionally distinct processes involved in the comprehension of highly restricted lexical-semantic relations (antonyms). We sought to differentiate between influences of semantic relatedness (which are independent of the experimental setting) and processes related to predictability (which differ as a function of the experimental environment). To this end, we conducted three ERP studies contrasting the processing of antonym relations (black-white) with that of related (black-yellow) and unrelated (black-nice) word pairs. Whereas the lexical-semantic manipulation was kept constant across experiments, the experimental environment and the task demands varied: Experiment 1 presented the word pairs in a sentence context of the form The opposite of X is Y and used a sensicality judgment. Experiment 2 used a word pair presentation mode and a lexical decision task. Experiment 3 also examined word pairs, but with an antonymy judgment task. All three experiments revealed a graded N400 response (unrelated > related > antonyms), thus supporting the assumption that semantic associations are processed automatically. In addition, the experiments revealed that, in highly constrained task environments, the N400 gradation occurs simultaneously with a P300 effect for the antonym condition, thus leading to the superficial impression of an extremely “reduced” N400 for antonym pairs. Comparisons across experiments and participant groups revealed that the P300 effect is not only a function of stimulus constraints (i.e., sentence context) and experimental task, but that it is also crucially influenced by individual processing strategies used to achieve successful task performance.

scholarly journals The Effects of Emotional Content on Phonological Processing in Children Who Stutter

2020 ◽  
Vol 18 (4) ◽  
pp. 431-444
Author(s):  
Sousan Salehi ◽  
◽  
Ahmad Reza Khatoonabadi ◽  
Mahmoud Reza Ashrafi ◽  
Ghasem Mohammadkhani ◽  
...  
Keyword(s):  
Reaction Time ◽  
Language Processing ◽  
Phonological Processing ◽  
Repeated Measures ◽  
Event Related Potential ◽  
Emotional Content ◽  
Time Range ◽  
High Time Resolution ◽  
Similar Distribution ◽  
Emotional Words

Objectives: Stuttering and phonological processing are mutually related. Emotion is an effective factor in fluency and language processing; however, its underlying neural mechanism remains unclear. Event-Related Potential (ERP) is a non-invasive highly-beneficial method with high time resolution for language processing. The present study aimed to explore phonological processing in emotional words in Children Who Stutter (CWS), compared to Typically-Developing Children (TDC). Methods: Ten Persian-speaking CWS (3 girls, 7 boys), aged 7-10 years (Mean±SD = 8.9±0.11) and 10 TDC who are matched in age (Mean±SD = 8.7±0.12) and gender were given 120 emotional words (high-valence low-valence) and neutral words to read. Phonological processing was measured by the aloud reading task, while ERP was simultaneously recorded. The collected results were analyzed as behavioral (reaction time and reading accuracy) and electrophysiological (amplitude and topography). Repeated-measures Analysis of Variance (ANOVA) and Independent Samples t-test were used for between-group comparisons. Results: The obtained behavioral data included Reaction Time (RT) and accuracy. There were no significant differences between the explored CWS and TDC in RT and accuracy (P>0.05). The mean value of amplitudes presented significant differences between CWS and TDC in language processing areas (P<0.05). The collected results indicated higher mean values of amplitude for neutral words. The distribution highly differed between the investigated CWS and TDC in neutral and negative words. However, there were similarities in positive words in distribution between the study groups. Discussion: The studied CWS and TDC were similar concerning behavioral results. High-valence words in the CWS group presented a higher similar distribution, compared to the TDC groups; however, low-valence words in the explored CWS had a more similar amplitude to the TDC group for neutral words. Then, emotional content facilitated phonological processing in the investigated CWS in the given time range.

Twelve-month-old infants learn crossmodal associations between visual objects and natural sounds in ecologically valid situations

2012 ◽  
Vol 25 (0) ◽  
pp. 117 ◽  
Author(s):  
Yi-Chuan Chen ◽  
Gert Westermann
Keyword(s):  
Ecological Validity ◽  
Real Life ◽  
Visual Object ◽  
Eye Tracker ◽  
Natural Sounds ◽  
Object Processing ◽  
Association Learning ◽  
Visual Objects ◽  
Crossmodal Associations ◽  
Novel Associations

Infants are able to learn novel associations between visual objects and auditory linguistic labels (such as a dog and the sound /dɔg/) by the end of their first year of life. Surprisingly, at this age they seem to fail to learn the associations between visual objects and natural sounds (such as a dog and its barking sound). Researchers have therefore suggested that linguistic learning is special (Fulkerson and Waxman, 2007) or that unfamiliar sounds overshadow visual object processing (Robinson and Sloutsky, 2010). However, in previous studies visual stimuli were paired with arbitrary sounds in contexts lacking ecological validity. In the present study, we create animations of two novel animals and two realistic animal calls to construct two audiovisual stimuli. In the training phase, each animal was presented in motions that mimicked animal behaviour in real life: in a short movie, the animal ran (or jumped) from the periphery to the center of the monitor, and it made calls while raising its head. In the test phase, static images of both animals were presented side-by-side and the sound for one of the animals was played. Infant looking times to each stimulus were recorded with an eye tracker. We found that following the sound, 12-month-old infants preferentially looked at the animal corresponding to the sound. These results show that 12-month-old infants are able to learn novel associations between visual objects and natural sounds in an ecologically valid situation, thereby challenging our current understanding of the development of crossmodal association learning.

Comparison of Early Cortical Networks in Efficient and Inefficient Visual Search: An Event-Related Potential Study

2003 ◽  
Vol 15 (7) ◽  
pp. 1039-1051 ◽  
Author(s):  
Ute Leonards ◽  
Julie Palix ◽  
Christoph Michel ◽  
Vicente Ibanez
Keyword(s):  
Event Related Potentials ◽  
Temporal Correlation ◽  
Temporal Analysis ◽  
Search Display ◽  
Stimulus Onset ◽  
Event Related Potential ◽  
Time Range ◽  
Cortical Networks ◽  
Related Potentials ◽  
Spatio Temporal

Functional magnetic resonance imaging studies have indicated that efficient feature search (FS) and inefficient conjunction search (CS) activate partially distinct frontoparietal cortical networks. However, it remains a matter of debate whether the differences in these networks reflect differences in the early processing during FS and CS. In addition, the relationship between the differences in the networks and spatial shifts of attention also remains unknown. We examined these issues by applying a spatio-temporal analysis method to high-resolution visual event-related potentials (ERPs) and investigated how spatio-temporal activation patterns differ for FS and CS tasks. Within the first 450 msec after stimulus onset, scalp potential distributions (ERP maps) revealed 7 different electric field configurations for each search task. Configuration changes occurred simultaneously in the two tasks, suggesting that contributing processes were not significantly delayed in one task compared to the other. Despite this high spatial and temporal correlation, two ERP maps (120–190 and 250–300 msec) differed between the FS and CS. Lateralized distributions were observed only in the ERP map at 250–300 msec for the FS. This distribution corresponds to that previously described as the N2pc component (a negativity in the time range of the N2 complex over posterior electrodes of the hemisphere contralateral to the target hemifield), which has been associated with the focusing of attention onto potential target items in the search display. Thus, our results indicate that the cortical networks involved in feature and conjunction searching partially differ as early as 120 msec after stimulus onset and that the differences between the networks employed during the early stages of FS and CS are not necessarily caused by spatial attention shifts.

Reaction Time for Object Categorization Is Predicted by Representational Distance

2014 ◽  
Vol 26 (1) ◽  
pp. 132-142 ◽  
Author(s):  
Thomas A. Carlson ◽  
J. Brendan Ritchie ◽  
Nikolaus Kriegeskorte ◽  
Samir Durvasula ◽  
Junsheng Ma
Keyword(s):  
Decision Making ◽  
Temporal Cortex ◽  
Internal Representation ◽  
Inferior Temporal Cortex ◽  
Object Categorization ◽  
Object Representations ◽  
Multivariate Pattern Analysis ◽  
Individual Object ◽  
Multivariate Pattern ◽  
The Brain

How does the brain translate an internal representation of an object into a decision about the object's category? Recent studies have uncovered the structure of object representations in inferior temporal cortex (IT) using multivariate pattern analysis methods. These studies have shown that representations of individual object exemplars in IT occupy distinct locations in a high-dimensional activation space, with object exemplar representations clustering into distinguishable regions based on category (e.g., animate vs. inanimate objects). In this study, we hypothesized that a representational boundary between category representations in this activation space also constitutes a decision boundary for categorization. We show that behavioral RTs for categorizing objects are well described by our activation space hypothesis. Interpreted in terms of classical and contemporary models of decision-making, our results suggest that the process of settling on an internal representation of a stimulus is itself partially constitutive of decision-making for object categorization.

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