Sensation seeking and error processing

Sensation seeking is defined by a strong need for varied, novel, complex, and intense stimulation, and a willingness to take risks for such experience. Several theories propose that the insensitivity to negative consequences incurred by risks is one of the hallmarks of sensation‐seeking behaviors. In this study, we investigated the time course of error processing in sensation seeking by recording event‐related potentials (ERPs) while high and low sensation seekers performed an Eriksen flanker task. Whereas there were no group differences in ERPs to correct trials, sensation seeking was associated with a blunted error‐related negativity (ERN), which was female‐specific. Further, different subdimensions of sensation seeking were related to ERN amplitude differently. These findings indicate that the relationship between sensation seeking and error processing is sex‐specific.     

Temporal dynamic modulation of acute stress on error processing in healthy males

Error processing is critical for adaptive behaviors. Acute stress has been found to influence error processing. However, the neural dynamic correlates underlying this modulation remain elusive. To address this issue, we recruited 39 healthy male participants, who performed a two‐session task before and after an acute stress test while their behavioral and EEG data were recorded. The participants were randomly exposed to either a stress condition (Maastricht Acute Stress Test) or a control condition. The stress test consisted of several hand immersion tasks (ice‐cold water, 2°C) and mental arithmetic tasks. A color‐word Stroop task was used to investigate the stress effect on error responses. Based on the level of stress‐induced cortisol, the participants in the stress group were further classified as low (N = 13) or high (N = 13) cortisol responders. The results indicated that only in the high cortisol responders, the error‐related negativity (ERN) amplitude was reduced after acute stress. In addition, the ?ERN in the high cortisol responders was significantly smaller than that in the low cortisol responders. These results suggest that acute stress impairs error detection. However, the error positivity amplitudes increased in the stress group compared to the control group, indicating that acute stress leads to greater error assessment. Taken together, these results suggest that acute stress impairs error detection, which is modulated by individuals’ response level following acute stress, and leads to more emotional and/or motivational responses to the error signal once the error is consciously realized.     

Developmental trends of performance monitoring measures in 7‐ to 25‐year‐olds: Unraveling the complex nature of brain measures

This study explores how trial‐to‐trial latency variability contributes to the developmental trends observed in ERN amplitude found in the incorrect trials of a performance monitoring task, the visual flanker task. An Adaptive Woody filter was used to measure and correct for the trial‐to‐trial latency variability of the ERN in 240 participants aged 7–25 years. Using three measures of latency variability, the degree of trial‐to‐trial latency variability was shown to decrease as the age of the participants increased from 7 to 25 years. The success of the Adaptive Woody filter technique to remove the trial‐to‐trial latency variability was demonstrated in a straightforward manner by the significant changes in the measures of fit and intraindividual variability obtained before and after applying the filter. After the latency variability effects were removed and adjusted averaged ERPs were obtained, a more subtle but significant nonlinear developmental trend was still found in the amplitude of the ERN component.     

Neural correlates of successful and partial inhibitions in children: An ERP study

This experiment used event‐related potentials (ERPs) to investigate the neural processes underlying the development of response inhibition in a modified version of the go/no‐go paradigm [Cragg and Nation [2008] Developmental Science 11(6): 819–827]. N2 and P3 ERP components on correct go trials and partial and successful inhibitions were compared in 7‐ and 9‐year‐old children. A larger N2 effect on successful inhibitions was found in 9‐year‐olds compared to 7‐year‐olds at fronto‐central electrodes. N2 amplitude was positively related to behavioral performance in the 7‐year‐olds suggesting it may reflect inhibitory processes; however, this relationship was not present in the 9‐year‐olds. Age differences were also apparent in the go P3, perhaps indicating differences in stimulus processing. The no‐go P3 component was larger on successful than partial inhibitions. In contrast, there was no difference in N2 amplitude between partial and successful inhibitions. A significant difference was found in N2 latency however. This suggests that inhibitory processes are similar in both cases but initiated earlier on successful inhibitions. N2 latency was also shorter in 9‐year‐olds than 7‐year‐olds supporting an increase in the efficiency of response inhibition with age. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 533–543, 2009.     

Empathy and error processing

Recent research suggests a relationship between empathy and error processing. Error processing is an evaluative control function that can be measured using post‐error response time slowing and the error‐related negativity (ERN) and post‐error positivity (Pe) components of the event‐related potential (ERP). Thirty healthy participants completed two measures of empathy, the Interpersonal Reactivity Index (IRI) and the Empathy Quotient (EQ), and a modified Stroop task. Post‐error slowing was associated with increased empathic personal distress on the IRI. ERN amplitude was related to overall empathy score on the EQ and the fantasy subscale of the IRI. The Pe and measures of empathy were not related. Results remained consistent when negative affect was controlled via partial correlation, with an additional relationship between ERN amplitude and empathic concern on the IRI. Findings support a connection between empathy and error processing mechanisms.     

Development of neural processes mediating rhyme judgments: Phonological and orthographic interactions

Development of neural processes underlying integration of phonological and orthographic information were assessed by measuring event-related brain potentials (ERPs), judgment accuracies and reaction times (RTs) in 20 children (9-10 years) and 20 adults performing visual rhyme judgments. Half the trials were phonologically and orthographically congruent across the prime-target pairs (e.g., thrown-own, cake-own), and half were incongruent (e.g., gown-own, cone-own). For both children and adults, behavioral performance was most affected when different phonological representations had to be encoded from similar orthographic representations (e.g., gown-own), and the amplitudes of the N350 reflected effects of both rhyme and phonological/orthographic congruency. Latencies of the N350 were shorter over the left hemisphere only in adults, and phonological/orthographic incongruence produced greater delays in children's processing. Therefore, it appears that neural systems mediating rhyming judgments develop early; however, adults exhibit increased efficiency for left-hemisphere processing and are less affected by interference from incongruent phonological and orthographic codes.     

Developmental differences in learning and error processing: Evidence from ERPs

This study examined developmental differences in the ERP correlates of internal and external error processing (ERN and FRN) during learning. A probabilistic learning task was applied in which feedback validity was manipulated. The behavioral data showed similar accuracy for children and adults when feedback was valid, whereas age differences were obtained when it was partially invalid. We found no reduction of the ERN for children compared to adults when performance levels were equated. Yet, contrary to adults, children did not differentiate between responses when feedback was partially invalid, indicating that they are less able to represent the correctness of a response when there is interference during learning. Moreover, we found a larger FRN and reduced ERP learning effects for positive feedback for children, suggesting that they are more sensitive to external error feedback and less able to disengage from positive feedback during learning.     

The N400 in beginning readers

In an event-related potentials study of brain-behavior relations during learning-to-read, girls in first grade viewed known words, unknown words, difficult words, and nonwords presented in list form. Participants were divided into low-ability and high-ability reading groups based on standardized test scores. During the 300- to 600-ms epoch, low-ability readers lacked a substantial N400 while high-ability readers evidenced a large, widely distributed negativity to all word types. During the 600- to 1,000-ms epoch, high-ability readers showed effects of repetition while low-ability readers did not. The findings indicate a less selective neurocognitive word-processing system in children as compared to adults and suggest that the N400 may serve as an oblique index of the automaticity of lower level processing.     

Chronic medication does not affect hyperactive error responses in obsessive‐compulsive disorder

Patients with obsessive‐compulsive disorder (OCD) show an increased error‐related negativity (ERN), yet previous studies have not controlled for medication use, which may be important given evidence linking performance monitoring to neurotransmitter systems targeted by treatment, such as serotonin. In an examination of 19 unmedicated OCD patients, 19 medicated OCD patients, 19 medicated patient controls without OCD, and 21 unmedicated healthy controls, we found greater ERNs in OCD patients than in controls, irrespective of medication use. Severity of generalized anxiety and depression was associated with ERN amplitude in controls but not patients. These data confirm previous findings of an exaggerated error response in OCD, further showing that it cannot be attributed to medication. The absence in patients of a relationship between ERN amplitude and anxiety/depression, as was found in controls, suggests that elevated error signals in OCD may be disorder‐specific.     

Resting cardiac vagal tone predicts intraindividual reaction time variability during an attention task in a sample of young and healthy adults

Intraindividual reaction time variability (IIV), defined as the variability in trial‐to‐trial response times, is thought to serve as an index of central nervous system function. As such, greater IIV reflects both poorer executive brain function and cognitive control, in addition to lapses in attention. Resting‐state vagally mediated heart rate variability (vmHRV), a psychophysiological index of self‐regulatory abilities, has been linked with executive brain function and cognitive control such that those with greater resting‐state vmHRV often perform better on cognitive tasks. However, research has yet to investigate the direct relationship between resting vmHRV and task IIV. The present study sought to examine this relationship in a sample of 104 young and healthy participants who first completed a 5‐min resting‐baseline period during which resting‐state vmHRV was assessed. Participants then completed an attentional (target detection) task, where reaction time, accuracy, and trial‐to‐trial IIV were obtained. Results showed resting vmHRV to be significantly related to IIV, such that lower resting vmHRV predicted higher IIV on the task, even when controlling for several covariates (including mean reaction time and accuracy). Overall, our results provide further evidence for the link between resting vmHRV and cognitive control, and extend these notions to the domain of lapses in attention, as indexed by IIV. Implications and recommendations for future research on resting vmHRV and cognition are discussed.     

Neural correlates of visual recognition in 3-month-old infants: the role of experience

Early experiences contribute powerfully to the development of neural systems that underlie various perceptual and cognitive abilities in humans. In one of the first studies to systematically control infants' exposure to a familiar object, we examined the effects of controlled experience on the neural correlates of visual recognition in two groups of infants. One group received 1 month of in‐home familiarization to a 3D model of a female face. Another group received 1.5 min of in‐lab familiarization to the 3D model of a female face, creating two conditions that differed in the amount and, importantly, the context of exposure to a familiar stimulus. Following familiarization, event‐related potentials (ERPs) were recorded at 3 months of age while infants viewed pictures of the familiar face and an unfamiliar face. Results demonstrated that while both groups of infants discriminated between the familiar and unfamiliar faces, the pattern of neural processing was reversed for the two groups. Thus, the amount and context of visual exposure altered the neural correlates of recognition processes in young infants. © 2011 Wiley Periodicals, Inc. Dev Psychobiol 53:416–424, 2011.     

Electrocortical and behavioral measures of response monitoring in young children during a Go/No-Go task

The current study examined behavioral measures and response‐locked event‐related brain potentials (ERPs) derived from a Go/No‐Go task in a large (N = 328) sample of 5‐ to 7‐year‐olds in order to better understand the early development of response monitoring and the impact of child age and sex. In particular, the error‐related negativity (ERN, defined on both error trials alone and the difference between error and correct trials, or ΔERN), correct response negativity (CRN), and error positivity (P_e) were examined. Overall, the ERN, CRN, and the P_e were spatially and temporally similar to those measured in adults and older children. Even within our narrow age range, older children were faster and more accurate; a more negative ΔERN and a more positive P_e were associated with: increasing age, increased accuracy, and faster reaction times on errors, suggesting these enhanced components reflected more efficient response monitoring of errors over development. Girls were slower and more accurate than boys, although both genders exhibited comparable ERPs. Younger children and girls were characterized by increased posterror slowing, although they did not demonstrate improved posterror accuracy. Posterror slowing was also related to a larger P_e and reduced posterror accuracy. Collectively, these data suggest that posterror slowing may be unrelated to cognitive control and may, like the P_e, reflect an orienting response to errors. © 2011 Wiley Periodicals, Inc. Dev Psychobiol 54:139‐150, 2012.     

Neural signatures of face-voice synchrony in 5-month-old human infants

Infants' unitary perception of their multisensory world, including learning from people (faces and speech), hinges on temporal synchrony. Despite its importance, relatively little work has investigated the brain processes involved in infants' perception of temporal synchrony. In two experiments, we examined event-related brain potentials (ERPs) to asynchronous and synchronous audio-visual speech in infants. Both experiments showed the early auditory P2 was greater for the synchronously presented pairings and later attentional processing (Nc) was greater for asynchronous pairings. In addition, dynamic stimuli used in Experiment 2 produced a greater early visual response (N1) to the asynchronous condition and an enhanced memory-related slow wave (PSW) later for the synchronous condition. These results suggest that, like adults, auditory-visual integration for young infants begins early during sensory processing rather than later during higher-level cognitive processing. However, unlike adults, infants' brain responses may be biased towards synchrony. Furthermore, effects of attentional and memory processing confirm interpretations of behavioral looking patterns suggesting infants find synchrony more familiar.     

Predictive information and error processing: the role of medial-frontal cortex during motor control

We have recently provided evidence that an error-related negativity (ERN), an ERP component generated within medial-frontal cortex, is elicited by errors made during the performance of a continuous tracking task (O.E. Krigolson & C.B. Holroyd, 2006). In the present study we conducted two experiments to investigate the ability of the medial-frontal error system to evaluate predictive error information. In two experiments participants used a joystick to perform a computer-based continuous tracking task in which some tracking errors were inevitable. In both experiments, half of these errors were preceded by a predictive cue. The results of both experiments indicated that an ERN-like waveform was elicited by tracking errors. Furthermore, in both experiments the predicted error waveforms had an earlier peak latency than the unpredicted error waveforms. These results demonstrate that the medial-frontal error system can evaluate predictive error information.     

Orthographic and phonological processing in developing readers revealed by ERPs

The development of neurocognitive mechanisms in single word reading was studied in children ages 8–10 years using ERPs combined with priming manipulations aimed at dissociating orthographic and phonological processes. Transposed‐letter (TL) priming (barin–BRAIN vs. bosin–BRAIN) was used to assess orthographic processing, and pseudohomophone (PH) priming (brane–BRAIN vs. brant–BRAIN) was used to assess phonological processing. Children showed TL and PH priming effects on both the N250 and N400 ERP components, and the magnitude of TL priming correlated positively with reading ability, with better readers showing larger TL priming effects. Phonological priming, on the other hand, did not correlate with reading ability. The positive correlations between TL priming and reading ability in children points to a key role for flexible sublexical orthographic representations in reading development, in line with their hypothesized role in the efficient mapping of orthographic information onto semantic information in skilled readers.     

Visual stimulation enhances auditory processing in 3‐month‐old infants and adults

Behavioral work demonstrates human infants are sensitive to a host of intersensory properties and this sensitivity promotes early learning and memory. However, little is known regarding the neural basis of this ability in infants. Using event‐related potentials (ERPs) with infants and adults, we show that during passive viewing auditory evoked brain responses are increased with the presence of simultaneous visual stimulation. Results converge with previous adult neuroimaging studies, single‐cell recordings in nonhuman animals, and behavioral studies with human infants to provide evidence for an elevated status of multisensory stimulation in infancy. Furthermore, these results may provide a neural marker of multisensory audio‐visual processing in infants that can be used to test developmental theories of how information is integrated across the senses to form a unitary perception of the world. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 52:181–189, 2010     

Single trial time-frequency domain analysis of error processing in post-traumatic stress disorder

Error processing studies in psychology and psychiatry are relatively common. Event-related potentials (ERPs) are often used as measures of error processing, two such response-locked ERPs being the error-related negativity (ERN) and the error-related positivity (Pe). The ERN and Pe occur following committed error in reaction time tasks as low frequency (4-8Hz) electroencephalographic (EEG) oscillations registered at the midline fronto-central sites. We created an alternative method for analyzing error processing using time-frequency analysis in the form of a wavelet transform. A study was conducted in which subjects with PTSD and healthy control completed a forced-choice task. Single trial EEG data from errors in the task were processed using a continuous wavelet transform. Coefficients from the transform that corresponded to the theta range were averaged to isolate a theta waveform in the time-frequency domain. Measures called the time-frequency ERN and Pe were obtained from these waveforms for five different channels and then averaged to obtain a single time-frequency ERN and Pe for each error trial. A comparison of the amplitude and latency for the time-frequency ERN and Pe between the PTSD and control group was performed. A significant group effect was found on the amplitude of both measures. These results indicate that the developed single trial time-frequency error analysis method is suitable for examining error processing in PTSD and possibly other psychiatric disorders.