scholarly journals S-cone signals invisible to the motion system can improve motion extraction via grouping by color

2009 ◽  
Vol 26 (2) ◽  
pp. 237-248 ◽  
Author(s):  
JASNA MARTINOVIC ◽  
GEORG MEYER ◽  
MATTHIAS M. MÜLLER ◽  
SOPHIE M. WUERGER
Keyword(s):  
Event Related Potentials ◽  
Event Related Potential ◽  
Coherent Motion ◽  
Behavioral Experiment ◽  
Motion Processing ◽  
Global Motion ◽  
Local Motion ◽  
Motion System ◽  
Motion Extraction ◽  
Related Potentials

AbstractThe purpose of this study was to test whether color–motion correlations carried by a pure color difference (S-cone component only) can be used to improve global motion extraction. We also examined the neural markers of color–motion correlation processing in event-related potentials. Color and motion information was dissociated using a two-colored random dot kinematogram, wherein coherent motion and motion noise differed from each other only in their S-cone component, with spatial and temporal parameters set so that global motion processing relied solely on a constant L-M component. Hence, when color and the local motion direction are correlated, more efficient segregation of coherent motion can only be brought about by the S-cone difference, and crucially, this S-cone component does not provide any effective input to a global motion mechanism but only changes the color appearance of the moving dots. The color contrasts (vector length in the S vs. L-M plane) of both the dots carrying coherent motion and the dots moving randomly were fixed at motion discrimination threshold to ensure equal effectiveness for motion extraction. In the behavioral experiment, participants were asked to discriminate between coherent and random motion, and d′ was determined for three different conditions: uncorrelated, uncued correlated, and cued correlated. In the electroencephalographic experiment, participants discriminated direction of motion for uncued correlated and cued correlated conditions. Color–motion correlations were found to improve performance. Cueing a specific color also modulated the N1 component of the event-related potential, with sources in visual area middle temporal. We conclude that S-cone signals “invisible” to the motion system can influence the analysis by direction-selective motion mechanisms through grouping of local motion signals by color. This grouping mechanism must precede motion processing and is likely to be under attentional control.

Improving motion detection via anodal transcranial direct current stimulation

2020 ◽  
Vol 38 (5) ◽  
pp. 395-405
Author(s):  
Luca Battaglini ◽  
Federica Mena ◽  
Clara Casco
Keyword(s):  
Direct Current ◽  
Signal To Noise Ratio ◽  
Individual Performance ◽  
Coherent Motion ◽  
Motion Processing ◽  
Global Motion ◽  
Local Motion ◽  
Processing Efficiency ◽  
Temporal Area ◽  
Direct Current Stimulation

Background: To study motion perception, a stimulus consisting of a field of small, moving dots is often used. Generally, some of the dots coherently move in the same direction (signal) while the rest move randomly (noise). A percept of global coherent motion (CM) results when many different local motion signals are combined. CM computation is a complex process that requires the integrity of the middle-temporal area (MT/V5) and there is evidence that increasing the number of dots presented in the stimulus makes such computation more efficient. Objective: In this study, we explored whether anodal direct current stimulation (tDCS) over MT/V5 would increase individual performance in a CM task at a low signal-to-noise ratio (SNR, i.e. low percentage of coherent dots) and with a target consisting of a large number of moving dots (high dot numerosity, e.g. >250 dots) with respect to low dot numerosity (<60 dots), indicating that tDCS favour the integration of local motion signal into a single global percept (global motion). Method: Participants were asked to perform a CM detection task (two-interval forced-choice, 2IFC) while they received anodal, cathodal, or sham stimulation on three different days. Results: Our findings showed no effect of cathodal tDCS with respect to the sham condition. Instead, anodal tDCS improves performance, but mostly when dot numerosity is high (>400 dots) to promote efficient global motion processing. Conclusions: The present study suggests that tDCS may be used under appropriate stimulus conditions (low SNR and high dot numerosity) to boost the global motion processing efficiency, and may be useful to empower clinical protocols to treat visual deficits.

A Neuromorphic Recurrent Model for Figure-Ground Segregation of Coherent Motion

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 84-84
Author(s):  
W H A Beaudot
Keyword(s):  
Temporal Integration ◽  
Receptive Fields ◽  
Optimal Solution ◽  
Coherent Motion ◽  
Motion Processing ◽  
Global Motion ◽  
Local Motion ◽  
Aperture Problem ◽  
Visual Inputs ◽  
Spatial Convergence

A neuromorphic model of the retino-cortical motion processing stream is proposed which incorporates both feedforward and feedback mechanisms. The feedforward stream consists of motion integration from the retina to the MT area. Retinal spatiotemporal filtering provides X-like and Y-like visual inputs with band-pass characteristics to the V1 area (Beaudot, 1996 Perception25 Supplement, 30 – 31). V1 direction-selective cells respond to local motion resulting from nonlinear interactions between retinal inputs. MT direction-selective cells respond to global motion resulting from spatial convergence and temporal integration of V1 signals. This feedforward stream provides a fine representation of local motion in V1 and a coarse representation of global motion in MT. However, it is unable to deal with the aperture problem. Solving this problem requires the adjunction of local constraints related to both smoothness and discontinuity of coherent motion, as well as some minimisation techniques to obtain the optimal solution. We propose a plausible neural substrate for this computation by incorporating excitatory intracortical feedbacks in V1 and their modulation by reciprocal connections from MT. The underlying enhancement or depression of V1 responses according to the strength of MT responses reflects changes in the spatiotemporal properties of the V1 receptive fields. This mechanism induces a dynamic competition between local and global motion representations in V1. On convergence of these dynamics, responses of V1 direction-selective cells provide a fine representation of ‘true’ motion, thus solving the aperture problem and allowing a figure - ground segregation based on coherent motion. The model is compatible with recent anatomical, physiological, and psychophysical evidence [Bullier et al, 1996 Journal de Physiologie (Paris)90 217 – 220].

Motion Perception in Healthy Humans and Cognitive Disorders

2011 ◽  
pp. 156-161 ◽  
Author(s):  
Takao Yamasaki ◽  
Shozo Tobimatsu
Keyword(s):  
Motion Perception ◽  
Cognitive Disorders ◽  
Event Related Potentials ◽  
Coherent Motion ◽  
Motion Processing ◽  
Neural Basis ◽  
Healthy Humans ◽  
Dorsal Pathway ◽  
Close Relationship ◽  
Related Potentials

To elucidate how the dorsal visual pathway is functionally altered in mild cognitive impairment (MCI) and Alzheimer’s disease (AD) patients, first, the neural basis of motion perception in healthy young adults was examined by using visual event-related potentials (ERPs) and functional magnetic resonance imaging (fMRI) with coherent motion stimuli such as radial optic flow (OF) and horizontal motion (HO). Nonspecific, motion-related N170 from V5/MT and OF-specific P200 with an inferior parietal lobule (IPL) origin were obtained in ERPs. fMRI revealed the close relationship between IPL activity and OF stimuli. Next, coherent motion perception was assessed by the psychophysical thresholds for patients with AD and MCI, as well as ERPs for MCI patients. MCI patients manifested a selective elevation of the OF threshold, while AD patients exhibited higher psychophysical thresholds for both OF and HO. In ERPs, the P200 latency for OF (but not the N170 latency for OF and HO) was significantly prolonged in MCI patients. These findings indicate that patients with AD and MCI have impaired coherent motion processing due to higher levels of the dorsal pathway. In particular, OF processing related to the IPL is selectively impaired in patients with MCI. Therefore, a combined approach with psychophysics and ERPs using coherent motion (particularly OF) can be useful to discriminate MCI and AD patients from older but healthy adults.

Neural dynamics of trainee teachers' emotional conflict processing: An event-related potential study

2019 ◽  
Vol 47 (7) ◽  
pp. 1-9
Author(s):  
Li Jin ◽  
Xu Li ◽  
Jiamei Lu ◽  
Nianqu Chen ◽  
Lin Cheng ◽  
...  
Keyword(s):  
School Context ◽  
Event Related Potentials ◽  
Event Related Potential ◽  
The Body ◽  
Educational Context ◽  
Congruent Condition ◽  
Slow Potential ◽  
Emotional Conflict ◽  
Trainee Teachers ◽  
Related Potentials

We investigated emotional conflict in an educational context with an emotional body–word Stroop paradigm, examining whether the N450 (a late fronto-central phasic negative event-related potential signature) and slow potential (SP) effects could be evoked in trainee teachers. The N450 effect is characterized by topography and negative polarity of an incongruent minus congruent difference potential, and the SP effect has positive polarity (incongruent minus congruent difference potential). Positive and negative body language examples were obtained from pupils in an actual school context, and emotional words were selected. Compound stimuli were presented, each comprising a congruent or incongruent word displayed across a body image. Event-related potentials were recorded while participants judged body expression valence. Reaction times were longer and accuracies were lower for the incongruent compared to the congruent condition. The N450 component amplitude in the incongruent condition was more negative than in the congruent condition. Results showed a behavioral interference effect and an N450 effect for trainee teachers in this context, thus indicating that the body–word task was efficient in assessing emotional conflict in an educational context, and trainee teachers' perception of body expressions of students could be influenced by emotional signals. The findings further the understanding of emotional conflict in an educational context.

scholarly journals Eliciting and Recording Event Related Potentials (ERPs) in Behaviourally Unresponsive Populations: A Retrospective Commentary on Critical Factors

2021 ◽  
Vol 11 (7) ◽  
pp. 835
Author(s):  
Alexander Rokos ◽  
Richard Mah ◽  
Rober Boshra ◽  
Amabilis Harrison ◽  
Tsee Leng Choy ◽  
...  
Keyword(s):  
Event Related Potentials ◽  
Stimulus Presentation ◽  
Event Related Potential ◽  
Critical Factors ◽  
Healthy Elderly ◽  
States Of Consciousness ◽  
Long Latency ◽  
Eeg Data ◽  
Related Potentials ◽  
The Relationship

A consistent limitation when designing event-related potential paradigms and interpreting results is a lack of consideration of the multivariate factors that affect their elicitation and detection in behaviorally unresponsive individuals. This paper provides a retrospective commentary on three factors that influence the presence and morphology of long-latency event-related potentials—the P3b and N400. We analyze event-related potentials derived from electroencephalographic (EEG) data collected from small groups of healthy youth and healthy elderly to illustrate the effect of paradigm strength and subject age; we analyze ERPs collected from an individual with severe traumatic brain injury to illustrate the effect of stimulus presentation speed. Based on these critical factors, we support that: (1) the strongest paradigms should be used to elicit event-related potentials in unresponsive populations; (2) interpretation of event-related potential results should account for participant age; and (3) speed of stimulus presentation should be slower in unresponsive individuals. The application of these practices when eliciting and recording event-related potentials in unresponsive individuals will help to minimize result interpretation ambiguity, increase confidence in conclusions, and advance the understanding of the relationship between long-latency event-related potentials and states of consciousness.

scholarly journals Automaticity of Early Sexual Attention: An Event-Related Potential Study

Sexual Abuse ◽  
2021 ◽  
pp. 107906322110242
Author(s):  
Anastasios Ziogas ◽  
Benedikt Habermeyer ◽  
Wolfram Kawohl ◽  
Elmar Habermeyer ◽  
Andreas Mokros
Keyword(s):  
Sexual Orientation ◽  
Sexual Interest ◽  
Event Related Potentials ◽  
Forensic Assessment ◽  
Event Related Potential ◽  
Behavioral Measures ◽  
Sexual Preferences ◽  
Motor Responses ◽  
Related Potentials ◽  
Promising Line

A promising line of research on forensic assessment of paraphilic sexual interest focuses on behavioral measures of visual attention using sexual stimuli as distractors. The present study combined event-related potentials (ERPs) with behavioral measures to investigate whether detection of a hidden sexual preference can be improved with ERPs. Normal variants of sexual orientation were used for a proof-of-concept investigation. Accordingly, 40 heterosexual and 40 gay men participated in the study. Within each group, half of the participants were instructed to hide their sexual orientation. The results showed that a match between sexual orientation and stimulus delays responses and influences ERP before motor responses. Late ERP components showed higher potential in differentiating hidden sexual preferences than motor responses, thereby showing how ERPs can be used in combination with reaction time measures to potentially facilitate the detection of hidden sexual preferences.

Phonetic Encoding Contributes to the Processing of Linguistic Prosody at the Word Level: Cross-Linguistic Evidence From Event-Related Potentials

2021 ◽  
pp. 1-11
Author(s):  
Luodi Yu ◽  
Jiajing Zeng ◽  
Suiping Wang ◽  
Yang Zhang
Keyword(s):  
Auditory Processing ◽  
Event Related Potentials ◽  
Event Related Potential ◽  
Acoustic Cues ◽  
Prosodic Features ◽  
Speech Stimuli ◽  
Word Level ◽  
Acoustic Control ◽  
Related Potentials ◽  
Prosodic Phonology

Purpose This study aimed to examine whether abstract knowledge of word-level linguistic prosody is independent of or integrated with phonetic knowledge. Method Event-related potential (ERP) responses were measured from 18 adult listeners while they listened to native and nonnative word-level prosody in speech and in nonspeech. The prosodic phonology (speech) conditions included disyllabic pseudowords spoken in Chinese and in English matched for syllabic structure, duration, and intensity. The prosodic acoustic (nonspeech) conditions were hummed versions of the speech stimuli, which eliminated the phonetic content while preserving the acoustic prosodic features. Results We observed language-specific effects on the ERP that native stimuli elicited larger late negative response (LNR) amplitude than nonnative stimuli in the prosodic phonology conditions. However, no such effect was observed in the phoneme-free prosodic acoustic control conditions. Conclusions The results support the integration view that word-level linguistic prosody likely relies on the phonetic content where the acoustic cues embedded in. It remains to be examined whether the LNR may serve as a neural signature for language-specific processing of prosodic phonology beyond auditory processing of the critical acoustic cues at the suprasyllabic level.

scholarly journals The Role of Leadership Level in College Students’ Decision-Making: Evidence From Event-Related Potential Analysis

2021 ◽  
Vol 12 ◽  
Author(s):  
Yuwei Yang ◽  
Shunshun Du ◽  
Hui He ◽  
Chengming Wang ◽  
Xueke Shan ◽  
...  
Keyword(s):  
College Students ◽  
Decision Making ◽  
Event Related Potentials ◽  
Event Related Potential ◽  
Economic Decision Making ◽  
Significant Difference ◽  
Leadership Group ◽  
Related Potentials ◽  
Acceptance Rates ◽  
Economic Transaction

Although risk decision-making plays an important role in leadership practice, the distinction in behavior between humans with differing levels of leadership, as well as the underlying neurocognitive mechanisms involved, remain unclear. In this study, the Ultimatum Game (UG) was utilized in concert with electroencephalograms (EEG) to investigate the temporal course of cognitive and emotional processes involved in economic decision-making between high and low leadership level college students. Behavioral results from this study found that the acceptance rates in an economic transaction, when the partner was a computer under unfair/sub unfair condition, were significantly higher than in transactions with real human partners for the low leadership group, while there was no significant difference in acceptance rates for the high leadership group. Results from Event-Related Potentials (ERP) analysis further indicated that there was a larger P3 amplitude in the low leadership group than in the high leadership group. We concluded that the difference between high and low leadership groups was at least partly due to their different emotional management abilities.

scholarly journals ERP CORE: An Open Resource for Human Event-Related Potential Research

2020 ◽  
Author(s):  
Emily S. Kappenman ◽  
Jaclyn Farrens ◽  
Wendy Zhang ◽  
Andrew X Stewart ◽  
Steven J Luck
Keyword(s):  
Data Processing ◽  
Brain Activity ◽  
A Priori ◽  
Event Related Potentials ◽  
Event Related Potential ◽  
Error Related Negativity ◽  
Wide Range ◽  
Experiment Control ◽  
Related Potentials

Event-related potentials (ERPs) are noninvasive measures of human brain activity that index a range of sensory, cognitive, affective, and motor processes. Despite their broad application across basic and clinical research, there is little standardization of ERP paradigms and analysis protocols across studies. To address this, we created ERP CORE (Compendium of Open Resources and Experiments), a set of optimized paradigms, experiment control scripts, data processing pipelines, and sample data (N = 40 neurotypical young adults) for seven widely used ERP components: N170, mismatch negativity (MMN), N2pc, N400, P3, lateralized readiness potential (LRP), and error-related negativity (ERN). This resource makes it possible for researchers to 1) employ standardized ERP paradigms in their research, 2) apply carefully designed analysis pipelines and use a priori selected parameters for data processing, 3) rigorously assess the quality of their data, and 4) test new analytic techniques with standardized data from a wide range of paradigms.

scholarly journals The Relationship Between Childhood Emotional Abuse and Processing of Emotional Facial Expressions in Healthy Young Men: Event-Related Potential and Behavioral Evidence

2021 ◽  
Vol 12 ◽  
Author(s):  
Yutong Liu ◽  
Huini Peng ◽  
Jianhui Wu ◽  
Hongxia Duan
Keyword(s):  
Facial Expressions ◽  
Childhood Maltreatment ◽  
Emotional Abuse ◽  
Young Men ◽  
Event Related Potentials ◽  
Event Related Potential ◽  
Emotional Facial Expressions ◽  
Related Potentials ◽  
Childhood Emotional Abuse ◽  
The Relationship

Background: Individuals exposed to childhood maltreatment present with a deficiency in emotional processing in later life. Most studies have focused mainly on childhood physical or sexual abuse; however, childhood emotional abuse, a core issue underlying different forms of childhood maltreatment, has received relatively little attention. The current study explored whether childhood emotional abuse is related to the impaired processing of emotional facial expressions in healthy young men.Methods: The emotional facial processing was investigated in a classical gender discrimination task while the event-related potentials (ERPs) data were collected. Childhood emotional abuse was assessed by a Childhood Trauma Questionnaire (CTQ) among 60 healthy young men. The relationship between the score of emotional abuse and the behavioral and the ERP index of emotional facial expression (angry, disgust, and happy) were explored.Results: Participants with a higher score of childhood emotional abuse responded faster on the behavioral level and had a smaller P2 amplitude on the neural level when processing disgust faces compared to neutral faces.Discussion: Individuals with a higher level of childhood emotional abuse may quickly identify negative faces with less cognitive resources consumed, suggesting altered processing of emotional facial expressions in young men with a higher level of childhood emotional abuse.

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