what is usesd to document the time-course of neural events

by Dr. Itzel Collier Published 2 years ago Updated 1 year ago 8 min read

How do you record a neural activity?

Electroencephalography (EEG)

Electroencephalography, or EEG, is probably the second-best known technique for recording neural activity. Whereas fMRI records blood flow, a proxy of neuron activation, EEG directly records the brain's electrical activity via electrodes placed on the scalp of the subject.Mar 29, 2018

What part of the brain is responsible for time perception?

Dorsolateral prefrontal right cortex is considered as the region most involved in time perception. This have been observed in patients with lesions in the dorsolateral prefrontal right cortex, showing changes in the performance of temporal discrimination tasks.Apr 1, 2016

What is an EEG event?

1. An Alzheimer's disease event is composed by a set of small EEG signal segments of 50 ms, characterized by a common and single dynamic energy. Learn more in: Alzheimer's Electroencephalogram Event Scalp and Source Localization.

What is a neural event?

neural events (with phasing) are important for neural representation (rather than just neural architecture or snapshots of the network at a single time-step) neural event types can be realized differently on different networks, cf.Mar 14, 2019

How does the brain measure time?

The neural clock operates by organizing the flow of our experiences into an orderly sequence of events. This activity gives rise to the brain's clock for subjective time. Experience, and the succession of events within experience, are thus the substance of which subjective time is generated and measured by the brain.

How do we perceive time?

How we perceive time. Our 'sense' of time is unlike our other senses—i.e. taste, touch, smell, sight and hearing. With time, we don't so much sense it as perceive it. Essentially, our brains take a whole bunch of information from our senses and organize it in a way that makes sense to us, before we ever perceive it.Jul 2, 2013

What is ERP vs EEG?

Event-Related Potentials (ERP) use similar equipment to EEG, electrodes attached to the scalp. However, the key difference is that a stimulus is presented to a participant (for example a picture/sound) and the researcher looks for activity related to that stimulus.

What is the ERP technique?

The event-related potential (ERP) technique, in which neural responses to specific events are extracted from the EEG, provides a powerful noninvasive tool for exploring the human brain. This volume describes practical methods for ERP research along with the underlying theoretical rationale.

What is EEG used for?

The EEG is used to evaluate several types of brain disorders. When epilepsy is present, seizure activity will appear as rapid spiking waves on the EEG. People with lesions of their brain, which can result from tumors or stroke, may have unusually slow EEG waves, depending on the size and the location of the lesion.

What are the four conditions of a practice trial?

Practice trials were completed with feedback until the participant successfully answered at least one question for each of the four conditions (Self-Consistent, Self-Inconsistent, Other-Consistent, Other-Inconsistent).

What is the ToM task?

The current study combined a ToM task that required rapid processing of information about perspectives together with EEG recording. It is commonly supposed that ToM judgments require multiple functional and neural processes, perhaps including some that are truly specific to ToM, and most likely also including generic processes for executive control ( Van Overwalle, 2009 ). However, most studies of ToM have been unable to distinguish between these component processes and study their relative time course. The ToM task in the current study is unusually well suited to this purpose because existing behavioral data indicate a distinction between an initial process of perspective calculation followed by a process of selecting the appropriate (Self or Other) perspective to respond on a given trial. Perspective calculation is not disrupted when participants perform a dual task that taxes inhibitory control (suggesting that it does not require general cognitive processes for inhibition), whereas the same dual task does disrupt perspective selection ( Qureshi et al., 2010 ). By combining this task with EEG recording that allowed neural responses to the task to be monitored with high temporal precision, we found several distinct neural processes, indexed as ERP components. We discuss these components in turn.

What is the TP450 effect?

Although the TP450 effect was limited to a particular region of the scalp, it occurred simultaneously with activity of a larger posterior component. The larger component during this time window likely reflects occipital, temporal, and parietal activity that is shared across our conditions. However, the existence of this broad component simultaneously with the TP450 component of interest complicates unconstrained source analysis procedures, such as s-LORETA and unconstrained current source dipole analyses, particularly when deep sources are implicated. This complication was, in fact, observed in S-LORETA analyses. These analyses, which followed the constrained dipole analyses described here, confirmed that the source solutions using this unconstrained method were dominated by deep sources in the occipital, temporal, and parietal lobes in all conditions. Therefore, given our strong hypothesis that the differences observed in the TP450 component reflect differences in the posterior ToM region, the temporoparietal junction, we conducted confirmatory equivalent dipole analyses with dipoles located in the gray matter of the temporoparietal junction during the time of the TP450 component (fixed location, rotating amplitude vector) ( Fig. 4 ). A model with a unilateral dipole in the right TPJ (rTPJ) (Talairach coordinates: 60, −40, 20) accounted for 63, 60, or 70% of variance for the Self-Consistent, Other-Consistent, and Other-Inconsistent conditions, respectively; adding a second dipole in the left TPJ (lTPJ) [Talairach coordinates: +/−60, −40, 20 (e.g., bilateral TPJ dipoles)] added a significant amount of explained variance (27, 27, 21%, respectively). For the Self-Inconsistent scalp ERP, the unilateral rTPJ model accounted for 76% of the variance, and a bilateral model added only 13% explained variance. For all of these models, additional dipoles located in the medial prefrontal lobes did not add significant additional explained variance (<4%). This confirmatory source analysis for the TP450 component is consistent with a model of bilateral temporoparietal junction activity for Self-Consistent, Other-Consistent, and Other-Inconsistent; predominantly unilateral right temporoparietal junction involvement for Self-Inconsistent; and primarily posterior and lateral sources of brain activity underlying the TP450 results.

Abstract

Improvement in perception takes place within the training session and from one session to the next. The present study aims at determining the time course of perceptual learning as revealed by changes in auditory event-related potentials (ERPs) reflecting preattentive processes.

Footnotes

doi: 10.1101/lm.46502 Learn. Mem. 2002. 9: 138-150 Cold Spring Harbor Laboratory Press