scholarly journals Real brains in virtual worlds: Validating a novel oddball paradigm in virtual reality

2019 ◽  
Author(s):  
Jonathan W. P. Kuziek ◽  
Abdel R. Tayem ◽  
Jennifer I. Burrell ◽  
Eden X. Redman ◽  
Jeff Murray ◽  
...  

Electroencephalography (EEG) research is typically conducted in controlled laboratory settings. This limits the generalizability to real-world situations. Virtual reality (VR) sits as a transitional tool that provides tight experimental control with more realistic stimuli. To test the validity of using VR for event-related potential (ERP) research we used a well-established paradigm, the oddball task. For our first study, we compared VR to traditional, monitor-based stimulus presentation using visual and auditory oddball tasks while EEG data was recorded. We were able to measure ERP waveforms typically associated with such oddball tasks, namely the P3 and earlier N2 components, in both conditions. Our results suggest that ERPs collected using VR head mounted displays and typical monitors were comparable on measures of latency, amplitude, and spectral composition. In a second study, we implemented a novel depth-based oddball task and we were able to measure the typical oddball-related ERPs elicited by the presentation of near and far stimuli. Interestingly, we observed significant differences in early ERPs components between near and far stimuli, even after controlling for the effects of the oddball task. Current results suggest that VR can serve as a valid means of stimulus presentation in novel or otherwise inaccessible environments for EEG experimentation. We demonstrated the capability of a depth-based oddball in reliably eliciting a P3 waveform. We also found an interaction between the depth at which objects are presented and early ERP responses. Further research is warranted to better explain this influence of depth on the EEG and ERP activity.

2002 ◽  
Vol 16 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Antoinette R. Miller ◽  
J. Peter Rosenfeld ◽  
Matthew Soskins ◽  
Marianne Jhee

Abstract The P300 component of the event-related potential was recorded during two blocks of an autobiographical oddball task. All participants performed honestly during the first block (Phone), i.e., the oddball stimuli were phone numbers. During the second block (Birthday), in which the oddball stimuli were participants' birthdays, a Truth group (N = 13) performed honestly and a Malinger group (N = 14) simulated amnesia. Amnesia simulation significantly reduced P300 amplitudes, both between groups and within the Malinger group (Phone vs. Birthday), possibly because of an increase in task difficulty in the Malinger condition. Analysis of scaled amplitudes also indicated a trend for a feigning-related alteration in P300 topography. Bootstrapping of peak-to-peak amplitudes detected significantly more (93%) Malinger individuals than bootstrapping of baseline-to-peak amplitudes (64%). Bootstrapping also provided evidence of a feigning-related amplitude difference between oddball stimuli (i.e., Phone > Birthday) in 71% of Malinger group individuals. In this comparison, the peak-to-peak measure also performed significantly better in intraindividual diagnostics.


2021 ◽  
Vol 11 (7) ◽  
pp. 835
Author(s):  
Alexander Rokos ◽  
Richard Mah ◽  
Rober Boshra ◽  
Amabilis Harrison ◽  
Tsee Leng Choy ◽  
...  

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.


Author(s):  
Stefan Bittmann

Virtual reality (VR) is the term used to describe representation and perception in a computer-generated, virtual environment. The term was coined by author Damien Broderick in his 1982 novel “The Judas Mandala". The term "Mixed Reality" describes the mixing of virtual reality with pure reality. The term "hyper-reality" is also used. Immersion plays a major role here. Immersion describes the embedding of the user in the virtual world. A virtual world is considered plausible if the interaction is logical in itself. This interactivity creates the illusion that what seems to be happening is actually happening. A common problem with VR is "motion sickness." To create a sense of immersion, special output devices are needed to display virtual worlds. Here, "head-mounted displays", CAVE and shutter glasses are mainly used. Input devices are needed for interaction: 3D mouse, data glove, flystick as well as the omnidirectional treadmill, with which walking in virtual space is controlled by real walking movements, play a role here.


2020 ◽  
Vol 11 ◽  
Author(s):  
Xiaohong Liu ◽  
Hongliang Zhou ◽  
Chenguang Jiang ◽  
Yanling Xue ◽  
Zhenhe Zhou ◽  
...  

Alcohol dependence (AD) presents cognitive control deficits. Event-related potential (ERP) P300 reflects cognitive control-related processing. The aim of this study was to investigate whether cognitive control deficits are a trait biomarker or a state biomarker in AD. Participants included 30 AD patients and 30 healthy controls (HCs). All participants were measured with P300 evoked by a three-stimulus auditory oddball paradigm at a normal state (time 1, i.e., just after the last alcohol intake) and abstinence (time 2, i.e., just after a 4-week abstinence). The results showed that for P3a and P3b amplitude, the interaction effect for group × time point was significant, the simple effect for group at time 1 level and time 2 level was significant, and the simple effect for time point at AD group level was significant; however, the simple effect for time point at HC group level was not significant. Above results indicated that compared to HCs, AD patients present reductions of P3a/3b amplitude, and after 4-week alcohol abstinence, although P3a/3b amplitudes were improved, they were still lower than those of HCs. For P3a and P3b latencies, no significant differences were observed. These findings conclude that AD patients present cognitive control deficits that are reflected by P3a/3b and that cognitive control deficits in AD are trait- and state-dependent. The implication of these findings is helpful to understand the psychological and neural processes for AD, and these findings suggest that improving the cognitive control function may impact the treatment effect for AD.


2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
M. Korostenskaja ◽  
K. Dapsys ◽  
A. Siurkute ◽  
A. Dudlauskaite ◽  
A. Pragaraviciene ◽  
...  

Abnormalities in attention, memory and information processing are considered to be the primary deficits in schizophrenia. Event-related potential (ERP) P300 could reflect deficits in auditory information processing related to active attention in schizophrenia patients. Atypical antipsychotics tend to ameliorate cognitive deficits, however their effects on neural aspects of cognitive dysfunction have not been consistent.Aim:To investigate the effects of quetiapine on auditory information processing by using auditory P300.Methods:We examined 7 patients with schizoaffective disorder, depressive type and 7 age- and sex-matched healthy controls. ERPs were elicited during active auditory “oddball” paradigm. P300 was recorded before and after two weeks of treatment with quetiapine (468.7±143 mg/day).Results:Baseline P300 latencies were significantly delayed in patients compared with controls. Quetiapine did not change P300 amplitudes. However, it normalized P300 latency. These results suggest that already after two weeks of treatment, quetiapine could have a beneficial effect on the active attention reflected in P300 in patients with schizoaffective disorder. Previous studies with antipsychotic drugs such as olanzapine and risperidone failed to show changes in P300 after this treatment interval.Conclusion:Quetiapine may be faster than other neuroleptics in ameliorating attentional dysfunction in patients with schizoaffective disorder. However, studies with a larger sample size must be conducted in order to confirm or reject the results of the current study.


2018 ◽  
Author(s):  
Jonathan W. P. Kuziek ◽  
Eden X. Redman ◽  
Graeme D. Splinter ◽  
Kyle E. Mathewson

AbstractBackgroundElectroencephalography (EEG) experiments often require several computers to ensure accurate stimulus presentation and data collection. However, this requirement can make it more difficult to perform such experiments in mobile settings within, or outside, the laboratoryNew MethodComputer miniaturisation and increasing processing power allow for EEG experiments to become more portable. Our goal is to show that a Latte Panda, a small Windows 10 computer, can be used to accurately collect EEG data in a similar manner to a laptop. Using a stationary bike, we also demonstrate that the Latte Panda will allow for more portable EEG experiments.ResultsSignificant and reliable MMN and P3 responses, event-related potentials (ERPs) typically associated with auditory oddball tasks, were observed and were consistent when using either the laptop or Latte Panda for EEG data collection. Similar MMN and P3 ERPs were also measured in the sitting and stationary biking conditions while using a Latte Panda for data collection.Comparison with Existing MethodData recorded by the Latte Panda computer produced comparable and equally reliable results to the laptop. As well, similar ERPs during sitting and biking would suggest that EEG experiments can be conducted in more mobile situations despite the increased noise and artefacts associated with muscle movement.ConclusionsOur results show that the Latte Panda is a low-cost, more portable alternative to a laptop computer for recording EEG data. Such a device will further allow for more portable and mobile EEG experimentation in a wider variety of environments.


2021 ◽  
Vol 12 ◽  
Author(s):  
Elena Selezneva ◽  
Michael Brosch ◽  
Sanchit Rathi ◽  
T. Vighneshvel ◽  
Nicole Wetzel

Pupil dilation in response to unexpected stimuli has been well documented in human as well as in non-human primates; however, this phenomenon has not been systematically compared between the species. This analogy is also crucial for the role of non-human primates as an animal model to investigate neural mechanisms underlying the processing of unexpected stimuli and their evoked pupil dilation response. To assess this qualitatively, we used an auditory oddball paradigm in which we presented subjects a sequence of the same sounds followed by occasional deviants while we measured their evoked pupil dilation response (PDR). We used deviants (a frequency deviant, a pink noise burst, a monkey vocalization and a whistle sound) which differed in the spectral composition and in their ability to induce arousal from the standard. Most deviants elicited a significant pupil dilation in both species with decreased peak latency and increased peak amplitude in monkeys compared to humans. A temporal Principal Component Analysis (PCA) revealed two components underlying the PDRs in both species. The early component is likely associated to the parasympathetic nervous system and the late component to the sympathetic nervous system, respectively. Taken together, the present study demonstrates a qualitative similarity between PDRs to unexpected auditory stimuli in macaque and human subjects suggesting that macaques can be a suitable model for investigating the neuronal bases of pupil dilation. However, the quantitative differences in PDRs between species need to be investigated in further comparative studies.


2005 ◽  
Vol 100 (2) ◽  
pp. 409-420
Author(s):  
Joel E. Alexander ◽  
Ben Crowson ◽  
Kelly Machan ◽  
Denesa Lockwood ◽  
Ronald G. Alexander ◽  
...  

The effects of self evaluation on the P300 event-related potential (ERP) were explored with 56 participants (16 men, 40 women; M age = 23.4 yr., SD = 1.2) across three conditions. The conditions included (1) a standard ERP auditory oddball discrimination between a random target (15% occurrence) and standard stimuli (85% occurrence), (2) the oddball task followed by the additional cognitive task of maintaining a mental count of the target tones, and (3) the oddball task followed by the additional cognitive task of self-evaluating whether they felt surprised by the current occurrence of the target tone. The added cognitive requirements for Conditions 2 and 3 required the subjects to maintain a cognitive readiness for the secondary stimulus-related task during their sensory discrimination response for the standard oddball task. During the self-evaluation condition, the P300 amplitude was significantly larger across all recording locations than the regular oddball condition and the cognitive count condition.


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