The impact of tone systems on the categorical perception of lexical tones: An event-related potentials study

2012 ◽  
Vol 27 (2) ◽  
pp. 184-209 ◽  
Author(s):  
Hong-Ying Zheng ◽  
James W. Minett ◽  
Gang Peng ◽  
William S-Y. Wang
2018 ◽  
Vol 30 (05) ◽  
pp. 1850034
Author(s):  
Yeganeh Shahsavar ◽  
Majid Ghoshuni

The main goal of this event-related potentials (ERPs) study was to assess the effects of stimulations in Stroop task in brain activities of patients with different degrees of depression. Eighteen patients (10 males, with the mean age [Formula: see text]) were asked to fill out Beck’s depression questionnaire. Electroencephalographic (EEG) signals of subjects were recorded in three channels (Pz, Cz, and Fz) during Stroop test. This test entailed 360 stimulations, which included 120 congruent, 120 incongruent, and 120 neutral stimulations. To analyze the data, 18 time features in each type of stimulus were extracted from the ERP components and the optimal features were selected. The correlation between the subjects’ scores in Beck’s depression questionnaires and the extracted time features in each recording channel was calculated in order to select the best features. Total area, and peak-to-peak time window in the Cz channel in both the congruent and incongruent stimulus showed significant correlation with Beck scores, with [Formula: see text], [Formula: see text] and [Formula: see text], [Formula: see text], respectively. Consequently, given the correlation between time features and the subjects’ Beck scores with different degrees of depression, it can be interpreted that in case of growth in degrees of depression, stimulations involving congruent images would produce more challenging interferences for the patients compared to incongruent stimulations which can be more effective in diagnosing the level of disorder.


2019 ◽  
Vol 11 (1) ◽  
pp. 80-115
Author(s):  
Eva Koderman

Abstract Anxiety is characterized by a sustained state of heightened vigilance due to uncertain danger, producing increased attention to a perceived threat in one's environment. To further examine this exploited the temporal resolution afforded by event-related potentials to investigate the impact of predictability of threat on early perceptual activity. We recruited 28 participants and utilized a within-subject design to examine hypervigilance in anticipation of shock, unpleasant picture and unpleasant sound during a task with unpredictable, predictable and no threat. We investigated if habituation to stimuli was present by asking the participants to rate unpleasantness and intensity of the stimuli before and after the experiment. We observed hypervigilance in the unpredictable threat of shock. Habituation was observed for the visual stimuli. The present study suggests that unpredictability enhances attentional engagement with neutral somatosensory stimuli when the threat is of the same modality, meaning we observed the presence of hypervigilance which is a characteristic of anxiety.


2019 ◽  
Author(s):  
Solange Denervaud ◽  
Jean-François Knebel ◽  
Emeline Mullier ◽  
Patric Hagmann ◽  
Micah M. Murray

Within an inherently dynamic environment, unexpected outcomes are part of daily life. Performance monitoring allows us to detect these events and adjust behavior accordingly. The necessity of such an optimal functioning has made error-monitoring a prominent topic of research over the last decades. Event-related potentials (ERPs) have differentiated between two brain components involved in error-monitoring: the error-related negativity (ERN) and error-related positivity (Pe) that are thought to reflect detection vs. emotional/motivational processing of errors, respectively. Both ERN and Pe depend on the protracted maturation of the frontal cortices and anterior cingulate through adolescence. To our knowledge, the impact of schooling pedagogy on error-monitoring and its brain mechanisms remains unknown and was the focus of the present study. Swiss schoolchildren completed a continuous recognition task while 64-channel EEG was recorded and later analyzed within an electrical neuroimaging framework. They were enrolled either in a Montessori curriculum (N=13), consisting of self-directed learning through trial-and-error activities with sensory materials, or a traditional curriculum (N=14), focused on externally driven activities mainly based on reward feedback. The two groups were controlled for age, gender, socio-economic status, parental educational style, and scores of fluid intelligence. The ERN was significantly enhanced in Montessori schoolchildren (driven by a larger response to errors), with source estimation differences localized to the cuneus and precuneus. In contrast, the Pe was enhanced in traditional schoolchildren (driven by a larger response to correct trials), with source estimation differences localized to the ventral anterior cingulate. Receiver operating characteristic (ROC) analysis demonstrated that the ERN and Pe could reliably classify if a child was following a Montessori or traditional curriculum. Brain activity subserving error-monitoring is modulated differently according to school pedagogy.


2007 ◽  
Vol 19 (10) ◽  
pp. 1595-1608 ◽  
Author(s):  
Leanne M. Williams ◽  
Andrew H. Kemp ◽  
Kim Felmingham ◽  
Belinda J. Liddell ◽  
Donna M. Palmer ◽  
...  

Although biases toward signals of fear may be an evolutionary adaptation necessary for survival, heightened biases may be maladaptive and associated with anxiety or depression. In this study, event-related potentials (ERPs) were used to examine the time course of neural responses to facial fear stimuli (versus neutral) presented overtly (for 500 msec with conscious attention) and covertly (for 10 msec with immediate masking to preclude conscious awareness) in 257 nonclinical subjects. We also examined the impact of trait anxiety and depression, assessed using psychometric ratings, on the time course of ERPs. In the total subject group, controlled biases to overtly processed fear were reflected in an enhancement of ERPs associated with structural encoding (120–220 msec) and sustained evaluation persisting from 250 msec and beyond, following a temporo-occipital to frontal topography. By contrast, covert fear processing elicited automatic biases, reflected in an enhancement of ERPs prior to structural encoding (80–180 msec) and again in the period associated with automatic orienting and emotion encoding (230–330 msec), which followed the reverse frontal to temporo-occipital topography. Higher levels of trait anxiety (in the clinical range) were distinguished by a heightened bias to covert fear (speeding of early ERPs), compared to higher depression which was associated with an opposing bias to overt fear (slowing of later ERPs). Anxiety also heightened early responses to covert fear, and depression to overt fear, with subsequent deficits in emotion encoding in each case. These findings are consistent with neural biases to signals of fear which operate automatically and during controlled processing, feasibly supported by parallel networks. Heightened automatic biases in anxiety may contribute to a cycle of hypervigilance and anxious thoughts, whereas depression may represent a “burnt out” emotional state in which evaluation of fear stimuli is prolonged only when conscious attention is allocated.


2007 ◽  
Vol 60 (11-12) ◽  
pp. 531-535 ◽  
Author(s):  
Otto Barak ◽  
Vesna Ivetic ◽  
Danka Filipovic ◽  
Nada Naumovic ◽  
Damir Lukac ◽  
...  

Introduction. A number of articles on physical activity analyze the effects of acute bouts of physical exercise on the whole body. These experiments mainly include questionnaires and measurements of reaction time. The use of event-related potentials in laboratories for functional diagnostics is only of recent date. The aim of this experiment was to give insights into the impact of physical activity of different intensity on the amplitude and latency of P300 cognitive potentials. Material and methods. After recording cognitive event-related potentials in 17 young (21.6?1.07 yrs) healthy adults (at Fz and Cz), the participants underwent a controlled bicycle ergometer exercise. Each exercise lasted 10 minutes, with successive increase in the intensity to 60%, 75% and 90% of the maximum pulse rate and maintaining this level of intensity for six minutes. Immediately after each bout of exercise, event-related potentials were recorded. Results. The amplitude of the P300 wave, following exercise intensity at 75% of the maximum pulse (Pmax) (Fz 15.00?4.57; Cz 18.63?8.83 mV) was statistically higher (p<0.05) than the amplitude of the P300 at rest (Fz 11.21?4.15 mV; Cz 13.40?8.04 mV), at 60% (Fz 11.86?5.11 mV; Cz 14.54?8.06 mV) and at 90% of maximum pulse (Fz 13.26?4.73 mV; Cz 14.91?8.91 mV). There were no statistically significant differences (p>0.05) between amplitudes at 60% of Pmax and values obtained at rest and at 90% of Pmax. Also, no statistically significant differences were recorded (p>0.05) among the latencies of P300 recorded at rest (Fz 323.57?13.24 ms; Cz 323.57?13.24 ms) and at 60% of Pmax (Fz 321.14?22.38 ms; Cz 321.86?22.88 ms), at 75% of Pmax (Fz 321.50?16.67 ms; Cz 322.50?14.60 ms) and at 90% of Pmax (Fz 326.29?7.85 ms; Cz 325.43?7.63 ms). Discusssion and Conclusion. Physical activity has a positive impact on cognitive functions. At intermediate intensities, the amplitude of P300 increases, but at submaximal intensities it decreases to values obtained at rest. However, the latency of P300 did not show a statistically significant change after different intensities of exercise.


2020 ◽  
Vol 150 (7) ◽  
pp. 1951-1957 ◽  
Author(s):  
Krishnamachari Srinivasan ◽  
Susan Thomas ◽  
Shilpa Anand ◽  
Mahesh Jayachandra ◽  
Tinku Thomas ◽  
...  

ABSTRACT Background Deficiency of vitamin B-12 is common in pregnant Indian women. Assessment of neurophysiological measures using event-related potentials (ERPs) may yield additional information on the effects of maternal B-12 supplementation on child brain function. Objectives The objective of the study was to evaluate the effects of vitamin B-12 supplementation (50 μg daily orally) during pregnancy on the childhood ERP measures of positive waveform ∼300 ms after stimulus (P300) and mismatch negativity. Methods This study was a follow-up of children born to pregnant women who received oral vitamin B-12 supplements (n = 62) compared with children of pregnant women who received placebo (n = 70) from a randomized controlled trial. The mean ± SD child age was 72 ± 1 mo. We used the Enobio system to assess the ERP measures P300 and mismatch negativity. Results There were no significant differences in the primary outcomes, amplitudes, and latencies of the P300 results and the mismatch negativity between children in the supplementation and placebo groups. We combined the intervention and placebo groups for secondary analyses. On multiple variable regression analysis after adjusting for treatment group, intrauterine growth restriction, and home environment, P300 amplitude in children was significantly higher in the lowest tertile of third-trimester maternal methylmalonic acid (MMA) concentrations (β = 3034.04; 95% CI: 923.24, 5144.83) compared with the highest MMA tertile (β = 1612.12; 95% CI: −258.86, 3483.10, P = 0.005). Conclusions While no significant effects of maternal vitamin B-12 supplementation on children's ERP measures were seen at 72 mo, elevated maternal MMA concentrations in the third trimester were negatively associated with P300 amplitude in children. It may be worthwhile to study the impact of maternal and infant vitamin B-12 supplementation on childhood brain structure and function in longer and larger trials. The parent trial was registered at clinicaltrials.gov as NCT00641862.


Sign in / Sign up

Export Citation Format

Share Document