Citation Context

...ychological studies suggest that at least some of these error processing mechanisms may be implemented in a brain circuit involving the anterior cingulate cortex and lateral prefrontal cortex ~Carter et al., 1998; Gehring & Knight, 2000; Kiehl, Liddle, & Hopfinger, 2000!. Progress on identifying the functional characteristics of the error monitor system has been made primarily through the study of two psychophysiological indices thought to be specifically associated with error processing: ~1! the error negativity ~Ne; Falkenstein, Hohnsbein, & Hoormann, 1991!, or errorrelated negativity ~ERN; Gehring, Goss, Coles, Meyer, & Donchin, 1993!. This is a sharp negative deflection in the event-related brain potential with a frontocentral distribution and peak approximately 80 ms after an incorrect response. The onset of the Ne can be as early as the first EMG activity leading to the incorrect response ~Gehring et al., 1993!; ~2! the error positivity ~Pe; Falkenstein et al., 1991; Falkenstein, Hohnsbein, & Hoormann, 1995!. This is a slow positive wave with centroparietal distribution, which often but not necessarily follows the Ne on incorrect trials. Although most investigators in the field have focused on validating the Ne and not...

Citation Context

...e errors. As has already been noted by Rabbitt ~e.g., 1967!, error processing, at least in the context of reaction time tasks, must involve an error detection mechanism and a set of remedial action mechanisms. The latter mechanisms are responsible for immediate error correction and for adjustments to response settings to prevent errors from recurring in the future. Recent neuroimaging studies and neuropsychological studies suggest that at least some of these error processing mechanisms may be implemented in a brain circuit involving the anterior cingulate cortex and lateral prefrontal cortex ~Carter et al., 1998; Gehring & Knight, 2000; Kiehl, Liddle, & Hopfinger, 2000!. Progress on identifying the functional characteristics of the error monitor system has been made primarily through the study of two psychophysiological indices thought to be specifically associated with error processing: ~1! the error negativity ~Ne; Falkenstein, Hohnsbein, & Hoormann, 1991!, or errorrelated negativity ~ERN; Gehring, Goss, Coles, Meyer, & Donchin, 1993!. This is a sharp negative deflection in the event-related brain potential with a frontocentral distribution and peak approximately 80 ms after an incorrect response. ...

Citation Context

...en made primarily through the study of two psychophysiological indices thought to be specifically associated with error processing: ~1! the error negativity ~Ne; Falkenstein, Hohnsbein, & Hoormann, 1991!, or errorrelated negativity ~ERN; Gehring, Goss, Coles, Meyer, & Donchin, 1993!. This is a sharp negative deflection in the event-related brain potential with a frontocentral distribution and peak approximately 80 ms after an incorrect response. The onset of the Ne can be as early as the first EMG activity leading to the incorrect response ~Gehring et al., 1993!; ~2! the error positivity ~Pe; Falkenstein et al., 1991; Falkenstein, Hohnsbein, & Hoormann, 1995!. This is a slow positive wave with centroparietal distribution, which often but not necessarily follows the Ne on incorrect trials. Although most investigators in the field have focused on validating the Ne and not the Pe, most authors appear to agree that the two indices represent different aspects of error processing ~see Falkenstein, Hoormann, Christ, & Hohnsbein, 2000!. The objective of the present research was to further our understanding of the psychological processes manifested by the Ne and Pe by examining the relationship between these psych...

Citation Context

...d peak approximately 80 ms after an incorrect response. The onset of the Ne can be as early as the first EMG activity leading to the incorrect response ~Gehring et al., 1993!; ~2! the error positivity ~Pe; Falkenstein et al., 1991; Falkenstein, Hohnsbein, & Hoormann, 1995!. This is a slow positive wave with centroparietal distribution, which often but not necessarily follows the Ne on incorrect trials. Although most investigators in the field have focused on validating the Ne and not the Pe, most authors appear to agree that the two indices represent different aspects of error processing ~see Falkenstein, Hoormann, Christ, & Hohnsbein, 2000!. The objective of the present research was to further our understanding of the psychological processes manifested by the Ne and Pe by examining the relationship between these psychophysiological indices and the presence or absence of awareness that a response error has occurred. It is likely that the Ne and Pe reflect the activity of two separate error monitoring processes. The early onset latency of the Ne with respect to the response ~e.g., Gehring et al., 1993! is suggestive of an internal error monitoring system, acting rapidly on information from central ~as opposed to peripheral! sourc...

Citation Context

...all studies of the Ne and Pe, overt response errors have been defined by an inappropriate button press, and participants are typically aware of this type of error. Here we report an experiment in which we obtained error-related ERP components, behavioral accuracy data, and trial-to-trial subjective accuracy judgments from participants performing an antisaccade task. Performance in this type of task shows many inappropriate, reflex-like saccades which are not perceived by the participant, even though they are immediately corrected ~Kramer, Hahn, Irwin, & Theeuwes, 2000; Mokler & Fischer, 1999; Theeuwes, Kramer, Hahn, & Irwin, 1998!. In the remainder of the introduction, we provide a selective review of empirical data and theory regarding the Ne and Pe ~for an extensive review of both components, see Falkenstein et al., 2000!. Then, we will discuss the antisaccade task and how it can be employed to investigate awareness of response errors. Error Negativity The Ne can be observed in both auditory tasks and visual tasks ~e.g., Falkenstein et al., 1991!, and has been reported after both hand and foot errors ~Holroyd, Dien, & Coles, 1998!, and after failures to inhibit eye movements in a saccade variant of the Go—No-go para...

Citation Context

...ady been noted by Rabbitt ~e.g., 1967!, error processing, at least in the context of reaction time tasks, must involve an error detection mechanism and a set of remedial action mechanisms. The latter mechanisms are responsible for immediate error correction and for adjustments to response settings to prevent errors from recurring in the future. Recent neuroimaging studies and neuropsychological studies suggest that at least some of these error processing mechanisms may be implemented in a brain circuit involving the anterior cingulate cortex and lateral prefrontal cortex ~Carter et al., 1998; Gehring & Knight, 2000; Kiehl, Liddle, & Hopfinger, 2000!. Progress on identifying the functional characteristics of the error monitor system has been made primarily through the study of two psychophysiological indices thought to be specifically associated with error processing: ~1! the error negativity ~Ne; Falkenstein, Hohnsbein, & Hoormann, 1991!, or errorrelated negativity ~ERN; Gehring, Goss, Coles, Meyer, & Donchin, 1993!. This is a sharp negative deflection in the event-related brain potential with a frontocentral distribution and peak approximately 80 ms after an incorrect response. The onset of the Ne can ...

Citation Context

... amplitude and the degree of error. Here, the degree of error refers to the difference between the correct and the incorrect response in terms of temporal ~Luu, Flaisch, et al., 2000! or spatial parameters ~Bernstein et al., 1995; Scheffers et al., 1996; Van’t Ent & Apkarian, 1999; but see Gehring et al., 1993!. The second type of evidence comes from studies showing that the Ne amplitude is smaller under circumstances that may be expected to affect the quality of perceptual processing. These circumstances include experimental settings in which participants have to respond under time pressure ~Falkenstein, Hohnsbein, Hoormann, & Blanke, 1990; see also Falkenstein et al., 2000!, have been deprived of sleep ~Scheffers, Humphrey, Stanny, Kramer, & Coles, 1999!, or are presented with degraded stimuli ~Scheffers & Coles, 2000!. The argument is that under these circumstances participants are likely to have a compromised representation of the response required by the stimulus. This, in turn, reduces the mismatch with the representation of the actual response in case of an error. One previous study has paid attention to the relation between the Ne and participants’ confidence in the accuracy of their response ~Scheffers & Coles, 2000!. I...

Citation Context

...t ~e.g., 1967!, error processing, at least in the context of reaction time tasks, must involve an error detection mechanism and a set of remedial action mechanisms. The latter mechanisms are responsible for immediate error correction and for adjustments to response settings to prevent errors from recurring in the future. Recent neuroimaging studies and neuropsychological studies suggest that at least some of these error processing mechanisms may be implemented in a brain circuit involving the anterior cingulate cortex and lateral prefrontal cortex ~Carter et al., 1998; Gehring & Knight, 2000; Kiehl, Liddle, & Hopfinger, 2000!. Progress on identifying the functional characteristics of the error monitor system has been made primarily through the study of two psychophysiological indices thought to be specifically associated with error processing: ~1! the error negativity ~Ne; Falkenstein, Hohnsbein, & Hoormann, 1991!, or errorrelated negativity ~ERN; Gehring, Goss, Coles, Meyer, & Donchin, 1993!. This is a sharp negative deflection in the event-related brain potential with a frontocentral distribution and peak approximately 80 ms after an incorrect response. The onset of the Ne can be as early as the first EMG activ...

Citation Context

...n reported after both hand and foot errors ~Holroyd, Dien, & Coles, 1998!, and after failures to inhibit eye movements in a saccade variant of the Go—No-go paradigm ~Van’t Ent & Apkarian, 1999!. Although there is some evidence that the amplitude of the Ne is related to more conservative response behavior on trials following an error ~Gehring et al., 1993!, the process reflected by the Ne does not seem to be involved in error correction ~e.g., Scheffers, Coles, Bernstein, Gehring, & Donchin, 1996!. Indeed, an Ne-like component has also been observed after failures to reach a response deadline ~Luu, Flaisch, & Tucker, 2000!, which allows no immediate error correction. The available evidence of the Ne is generally consistent with the proposal ~e.g., Bernstein, Scheffers, & Coles, 1995; Falkenstein et al., 1991; Scheffers et al., 1996! that the negativity following errors reflects the manifestation of an error detection system that checks actual behavior against an internal goal standard. The output of this error detection system may reflect both the cognitive and emotional significance of a deviation from the anticipated result ~see, e.g., Gehring et al., 1993; Kiehl et al., 2000!. In choice RT tasks, a represen...

Citation Context

...ipants characterized as highly susceptible to hypnosis, the Pe was essentially abolished under hypnosis as compared to a prehypnosis baseline that showed a clear Pe. Importantly, the Ne was fully unaffected in the hypnosis condition. To the extent that hypnosis can be regarded as a state of altered or lacking consciousness, this result appears nicely compatible with the hypothesis that the Pe is related to the conscious recognition of errors whereas the Ne is not. The Antisaccade Paradigm The antisaccade task ~e.g., Hallet, 1978; Nieuwenhuis, Ridderinkhof, De Jong, Kok, & Van der Molen, 2000; Roberts, Hager, & Heron, 1994! provides a suitable laboratory paradigm for the study of overt motor responses that do not reach awareness. In this task, participants are instructed to generate a saccade to the opposite side of a peripheral abrupt onset cue ~i.e., an antisaccade!. Because abrupt onset stimuli are well known to capture the eyes in an automatic fashion ~e.g., Theeuwes et al., 1998!, correct antisaccade performance requires controlled inhibition of the reflexive saccade towards the abrupt onset cue. A direction error is defined by a saccade in the direction of the cue, even if the eyes are immediately redirec...

Citation Context

...tely corrected ~Kramer, Hahn, Irwin, & Theeuwes, 2000; Mokler & Fischer, 1999; Theeuwes, Kramer, Hahn, & Irwin, 1998!. In the remainder of the introduction, we provide a selective review of empirical data and theory regarding the Ne and Pe ~for an extensive review of both components, see Falkenstein et al., 2000!. Then, we will discuss the antisaccade task and how it can be employed to investigate awareness of response errors. Error Negativity The Ne can be observed in both auditory tasks and visual tasks ~e.g., Falkenstein et al., 1991!, and has been reported after both hand and foot errors ~Holroyd, Dien, & Coles, 1998!, and after failures to inhibit eye movements in a saccade variant of the Go—No-go paradigm ~Van’t Ent & Apkarian, 1999!. Although there is some evidence that the amplitude of the Ne is related to more conservative response behavior on trials following an error ~Gehring et al., 1993!, the process reflected by the Ne does not seem to be involved in error correction ~e.g., Scheffers, Coles, Bernstein, Gehring, & Donchin, 1996!. Indeed, an Ne-like component has also been observed after failures to reach a response deadline ~Luu, Flaisch, & Tucker, 2000!, which allows no immediate error correctio...

Citation Context

...ly if they thought they had moved their eyes in the direction of the cue. To increase the proportion of direction errors, the task design included the following features. First, saccades were required in both the horizontal and the vertical dimension. Increasing the number of possible cue locations from two to four decreases antisaccade performance when locations are positioned along two orthogonal axes ~Delaney & Roberts, 1999!. Second, a gap of 200 ms was introduced between fixation point offset and cue onset. This feature is well known to increase error rates in the antisaccade task ~e.g., Munoz, Broughton, Goldring, & Armstrong, 1998!. A third feature included to increase the error rates was the use of a precue ~in approximately 50% of the trials, to prevent habituation; e.g., Fischer & Weber, 1996!, validly indicating the target location on each presentation.1 Thus, the antisaccade paradigm permitted the study of errorrelated brain activity in an experimental setting in which ~a! participants were always aware of the required response, as indicated by the rapid correction of both perceived and unperceived direction errors; ~b! at some level in the participants’ information processing system there was information about th...

Citation Context

...areness of response errors. Error Negativity The Ne can be observed in both auditory tasks and visual tasks ~e.g., Falkenstein et al., 1991!, and has been reported after both hand and foot errors ~Holroyd, Dien, & Coles, 1998!, and after failures to inhibit eye movements in a saccade variant of the Go—No-go paradigm ~Van’t Ent & Apkarian, 1999!. Although there is some evidence that the amplitude of the Ne is related to more conservative response behavior on trials following an error ~Gehring et al., 1993!, the process reflected by the Ne does not seem to be involved in error correction ~e.g., Scheffers, Coles, Bernstein, Gehring, & Donchin, 1996!. Indeed, an Ne-like component has also been observed after failures to reach a response deadline ~Luu, Flaisch, & Tucker, 2000!, which allows no immediate error correction. The available evidence of the Ne is generally consistent with the proposal ~e.g., Bernstein, Scheffers, & Coles, 1995; Falkenstein et al., 1991; Scheffers et al., 1996! that the negativity following errors reflects the manifestation of an error detection system that checks actual behavior against an internal goal standard. The output of this error detection system may reflect both the cognitive and emotional significance ...

Citation Context

...aradigm ~Van’t Ent & Apkarian, 1999!. Although there is some evidence that the amplitude of the Ne is related to more conservative response behavior on trials following an error ~Gehring et al., 1993!, the process reflected by the Ne does not seem to be involved in error correction ~e.g., Scheffers, Coles, Bernstein, Gehring, & Donchin, 1996!. Indeed, an Ne-like component has also been observed after failures to reach a response deadline ~Luu, Flaisch, & Tucker, 2000!, which allows no immediate error correction. The available evidence of the Ne is generally consistent with the proposal ~e.g., Bernstein, Scheffers, & Coles, 1995; Falkenstein et al., 1991; Scheffers et al., 1996! that the negativity following errors reflects the manifestation of an error detection system that checks actual behavior against an internal goal standard. The output of this error detection system may reflect both the cognitive and emotional significance of a deviation from the anticipated result ~see, e.g., Gehring et al., 1993; Kiehl et al., 2000!. In choice RT tasks, a representation of the actual response may be formed on the basis of some “efference copy” of the motor commands sent to the response effectors ~see Gehring et al., 1993!. A...

Citation Context

...ipants’ information processing system there was information about the actual incorrect response ~This seems trivial because the system produces that response itself.!; and ~c! participants were often not aware of response errors. If the monitoring processes manifested by the Ne and Pe are related to the processes associated with participants’ subjective identification of errors, then the associated components should be substantially affected after saccade direction errors that were not recognized by participants as such. More specifically, in line with previous empirical ~Kaiser et al., 1997; Vidal et al., 2000! and theoretical ~Falkenstein et al., 1991; 2000! contributions to the literature, we expected that awareness of response errors would significantly correlate with Pe measures but not with Ne measures. Method Participants Fifteen undergraduate students ~12 women! from the University of Amsterdam participated in this experiment. The participants, ranging in age from 18 to 23 years, received course credit for their participation. Three participants were replaced because their proportion of perceived or unperceived errors in the relevant ~horizontal; see Data Analysis section! dimension was smal...

Citation Context

...the study of two psychophysiological indices thought to be specifically associated with error processing: ~1! the error negativity ~Ne; Falkenstein, Hohnsbein, & Hoormann, 1991!, or errorrelated negativity ~ERN; Gehring, Goss, Coles, Meyer, & Donchin, 1993!. This is a sharp negative deflection in the event-related brain potential with a frontocentral distribution and peak approximately 80 ms after an incorrect response. The onset of the Ne can be as early as the first EMG activity leading to the incorrect response ~Gehring et al., 1993!; ~2! the error positivity ~Pe; Falkenstein et al., 1991; Falkenstein, Hohnsbein, & Hoormann, 1995!. This is a slow positive wave with centroparietal distribution, which often but not necessarily follows the Ne on incorrect trials. Although most investigators in the field have focused on validating the Ne and not the Pe, most authors appear to agree that the two indices represent different aspects of error processing ~see Falkenstein, Hoormann, Christ, & Hohnsbein, 2000!. The objective of the present research was to further our understanding of the psychological processes manifested by the Ne and Pe by examining the relationship between these psychophysiological indices and the presence or...

Citation Context

...epresentation of the correct response, but participants are not ~always! aware of errors in the execution of this response. Before describing our choice of paradigm, we briefly review the empirical evidence and theoretical notions regarding the Pe. Error Positivity The morphology, polarity, and scalp topography of the Pe are similar to those of the P3, a positive slow wave in the stimulusevoked ERP, which is maximal at centroparietal recording sites and peaks at 300 ms or more after task-relevant stimuli. Because of this similarity, Falkenstein et al. ~1991; see also Falkenstein et al., 2000; Leuthold & Sommer, 1999! interpreted the Pe as representing a second P3, elicited by the evaluation of the incorrect response. Thus, according to this interpretation, error trials are characterized by two successive P3 components, the first of which is sensitive to stimulus evaluation and the second of which is sensitive to the evaluation of the incorrect response ~which is usually a highly task-relevant event!. In contrast, there has been some debate ~e.g., Falkenstein et al., 1995! as to whether the Pe might reflect a delayed ~component of the! stimulus-evoked P3 complex contributing to the responselocked ERP. How...

Citation Context

... was in fact briefly aware of the error while it was happening. Awareness of an event is used here in a pragmatic sense, that is, in terms of whether information about the event is available for report briefly after it has taken place ~Scheffers & Coles, 2000, refer to this as “perceived accuracy”!. The question, then, is why participants fail to report so many of their errors. From a neurophysiological perspective, it has been argued ~see Mokler & Fischer, 1999! that saccade direction errors have a significant chance of remaining unrecognized, because they are generated mostly subcortically ~Schiller, 1998!. The increased size of the required corrective antisaccade ~compared to a direct antisaccade! probably remains unnoticed because voluntary saccades are specified in terms of the desired end position of the eye in the orbit ~Mays & Sparks, 1980; Schiller, 1998!, which is the same in either case. Another interesting explanation, at the psychological level, is offered in the Discussion. As in Mokler and Fischer ~1999!, participants in the present experiment were to judge their antisaccade performance at the end of each trial. The stimulus events and their relative timing are illustrated in Figu...

Citation Context

...oneous responses. The likely reason for this is that in almost all studies of the Ne and Pe, overt response errors have been defined by an inappropriate button press, and participants are typically aware of this type of error. Here we report an experiment in which we obtained error-related ERP components, behavioral accuracy data, and trial-to-trial subjective accuracy judgments from participants performing an antisaccade task. Performance in this type of task shows many inappropriate, reflex-like saccades which are not perceived by the participant, even though they are immediately corrected ~Kramer, Hahn, Irwin, & Theeuwes, 2000; Mokler & Fischer, 1999; Theeuwes, Kramer, Hahn, & Irwin, 1998!. In the remainder of the introduction, we provide a selective review of empirical data and theory regarding the Ne and Pe ~for an extensive review of both components, see Falkenstein et al., 2000!. Then, we will discuss the antisaccade task and how it can be employed to investigate awareness of response errors. Error Negativity The Ne can be observed in both auditory tasks and visual tasks ~e.g., Falkenstein et al., 1991!, and has been reported after both hand and foot errors ~Holroyd, Dien, & Coles, 1998!, and after failures to ...

Citation Context

... this is that in almost all studies of the Ne and Pe, overt response errors have been defined by an inappropriate button press, and participants are typically aware of this type of error. Here we report an experiment in which we obtained error-related ERP components, behavioral accuracy data, and trial-to-trial subjective accuracy judgments from participants performing an antisaccade task. Performance in this type of task shows many inappropriate, reflex-like saccades which are not perceived by the participant, even though they are immediately corrected ~Kramer, Hahn, Irwin, & Theeuwes, 2000; Mokler & Fischer, 1999; Theeuwes, Kramer, Hahn, & Irwin, 1998!. In the remainder of the introduction, we provide a selective review of empirical data and theory regarding the Ne and Pe ~for an extensive review of both components, see Falkenstein et al., 2000!. Then, we will discuss the antisaccade task and how it can be employed to investigate awareness of response errors. Error Negativity The Ne can be observed in both auditory tasks and visual tasks ~e.g., Falkenstein et al., 1991!, and has been reported after both hand and foot errors ~Holroyd, Dien, & Coles, 1998!, and after failures to inhibit eye movements in...

Citation Context

... participants performing a simple S-R compatibility task. In a group of participants characterized as highly susceptible to hypnosis, the Pe was essentially abolished under hypnosis as compared to a prehypnosis baseline that showed a clear Pe. Importantly, the Ne was fully unaffected in the hypnosis condition. To the extent that hypnosis can be regarded as a state of altered or lacking consciousness, this result appears nicely compatible with the hypothesis that the Pe is related to the conscious recognition of errors whereas the Ne is not. The Antisaccade Paradigm The antisaccade task ~e.g., Hallet, 1978; Nieuwenhuis, Ridderinkhof, De Jong, Kok, & Van der Molen, 2000; Roberts, Hager, & Heron, 1994! provides a suitable laboratory paradigm for the study of overt motor responses that do not reach awareness. In this task, participants are instructed to generate a saccade to the opposite side of a peripheral abrupt onset cue ~i.e., an antisaccade!. Because abrupt onset stimuli are well known to capture the eyes in an automatic fashion ~e.g., Theeuwes et al., 1998!, correct antisaccade performance requires controlled inhibition of the reflexive saccade towards the abrupt onset cue. A direction erro...

Citation Context

...ffers & Coles, 2000, refer to this as “perceived accuracy”!. The question, then, is why participants fail to report so many of their errors. From a neurophysiological perspective, it has been argued ~see Mokler & Fischer, 1999! that saccade direction errors have a significant chance of remaining unrecognized, because they are generated mostly subcortically ~Schiller, 1998!. The increased size of the required corrective antisaccade ~compared to a direct antisaccade! probably remains unnoticed because voluntary saccades are specified in terms of the desired end position of the eye in the orbit ~Mays & Sparks, 1980; Schiller, 1998!, which is the same in either case. Another interesting explanation, at the psychological level, is offered in the Discussion. As in Mokler and Fischer ~1999!, participants in the present experiment were to judge their antisaccade performance at the end of each trial. The stimulus events and their relative timing are illustrated in Figure 1. Participants were instructed to suppress a reflexive saccade, and to generate a direct antisaccade away from the abrupt onset cue as fast as they could. One second after cue onset, a cross was presented at the target location. At this poin...

Citation Context

...ask-relevant event!. In contrast, there has been some debate ~e.g., Falkenstein et al., 1995! as to whether the Pe might reflect a delayed ~component of the! stimulus-evoked P3 complex contributing to the responselocked ERP. However, there are several arguments favoring the hypothesis of an additional P3-like positivity over this latter possibility. First, although the P3 latency may be delayed to some extent on error trials ~Donchin, Gratton, Dupree, & Coles, 1988!, various reports of Pe latency would imply implausibly large latency shifts of the P3 on these trials ~Falkenstein et al., 1991; Kaiser, Barker, Haenschel, Baldeweg, & Gruzelier, 1997; Leuthold & Sommer, 1999!. Second, sometimes two positive peaks can be discerned in the stimulus-locked ERP associated with incorrect responses: one in the latency range of the classic, stimulus-evoked P3, and one after the incorrect response ~Falkenstein et al., 1991; Leuthold & Sommer, 1999!. A particularly convincing demonstration of two successive P3-like positive components on error trials can be found in Luu, Collins, and Tucker ~2000!. Using grandaverage voltage maps of the scalp, these authors show that the second, error-related positivity has a slightly more anterior distribution tha...

Citation Context

...incorrect response in terms of temporal ~Luu, Flaisch, et al., 2000! or spatial parameters ~Bernstein et al., 1995; Scheffers et al., 1996; Van’t Ent & Apkarian, 1999; but see Gehring et al., 1993!. The second type of evidence comes from studies showing that the Ne amplitude is smaller under circumstances that may be expected to affect the quality of perceptual processing. These circumstances include experimental settings in which participants have to respond under time pressure ~Falkenstein, Hohnsbein, Hoormann, & Blanke, 1990; see also Falkenstein et al., 2000!, have been deprived of sleep ~Scheffers, Humphrey, Stanny, Kramer, & Coles, 1999!, or are presented with degraded stimuli ~Scheffers & Coles, 2000!. The argument is that under these circumstances participants are likely to have a compromised representation of the response required by the stimulus. This, in turn, reduces the mismatch with the representation of the actual response in case of an error. One previous study has paid attention to the relation between the Ne and participants’ confidence in the accuracy of their response ~Scheffers & Coles, 2000!. In this study, participants performed an Eriksen flankers task in which they were required to respond to the identity ...

Citation Context

...Roetersstraat 15, 1018 WB Amsterdam, The Netherlands. E-mail: stn20@dds.nl. Psychophysiology, 38 ~2001!, 752–760. Cambridge University Press. Printed in the USA. Copyright © 2001 Society for Psychophysiological Research 752 has been initiated. In contrast, the timing of the Pe allows for the possibility of a second error monitoring process, which is informed by peripheral ~e.g., proprioceptive or reafferent! information indicating that an error has occurred. Note that a distinction between an “internal” and “external” error monitoring loop has often been made in models of motor control ~e.g., Cooke & Diggles, 1984!. Partly because of their timing with respect to the response, it is well-conceivable that the two error monitoring processes are differentially related to subjective awareness of response errors. For instance, Falkenstein et al. ~1991! have proposed that the early error-related ERP component, the Ne, “reflects a ~perhaps unconscious! mismatch between response selection and . . . response execution, whereas the slow wave @i.e., the Pe# reflects the conscious evaluation of the error” ~p. 454!. As we will argue below, there is already some indirect evidence in support of this proposal. In our e...

Citation Context

...required in both the horizontal and the vertical dimension. Increasing the number of possible cue locations from two to four decreases antisaccade performance when locations are positioned along two orthogonal axes ~Delaney & Roberts, 1999!. Second, a gap of 200 ms was introduced between fixation point offset and cue onset. This feature is well known to increase error rates in the antisaccade task ~e.g., Munoz, Broughton, Goldring, & Armstrong, 1998!. A third feature included to increase the error rates was the use of a precue ~in approximately 50% of the trials, to prevent habituation; e.g., Fischer & Weber, 1996!, validly indicating the target location on each presentation.1 Thus, the antisaccade paradigm permitted the study of errorrelated brain activity in an experimental setting in which ~a! participants were always aware of the required response, as indicated by the rapid correction of both perceived and unperceived direction errors; ~b! at some level in the participants’ information processing system there was information about the actual incorrect response ~This seems trivial because the system produces that response itself.!; and ~c! participants were often not aware of response errors. If the...

Citation Context

...in et al., 2000!. Hence, it has been argued that the Pe cannot be a correlate of an error correction process ~Falkenstein et al., 2000!. As noted above, an alternative interpretation of the Pe is that it reflects the conscious processing of the error event ~Falkenstein et al., 1991, 2000!. As such, it may be directly related to the controlled adjustment of response strategies following the recognition of an error, or it may reflect the conscious recognition of the error itself. To our knowledge, the relation between the Pe and indices of response strategy adjustments ~e.g., posterror slowing; Rabbitt, 1966! remains to be empirically investigated. However, some evidence suggests a relation between the Pe and conscious error recognition. First, Vidal, Hasbroucq, Grapperon, and Bonnet ~2000! have reported that in a two-choice manual response task overt motor errors are followed by an Ne and a Pe. In contrast, trials that were characterized by subthreshold muscle activation of the incorrect hand followed by the appropriate overt response showed a clear Ne but no Pe. It can be argued that a Pe was missing in these trials because subthreshold errors may be less likely to reach awareness, especially i...

Citation Context

...ents, the first of which is sensitive to stimulus evaluation and the second of which is sensitive to the evaluation of the incorrect response ~which is usually a highly task-relevant event!. In contrast, there has been some debate ~e.g., Falkenstein et al., 1995! as to whether the Pe might reflect a delayed ~component of the! stimulus-evoked P3 complex contributing to the responselocked ERP. However, there are several arguments favoring the hypothesis of an additional P3-like positivity over this latter possibility. First, although the P3 latency may be delayed to some extent on error trials ~Donchin, Gratton, Dupree, & Coles, 1988!, various reports of Pe latency would imply implausibly large latency shifts of the P3 on these trials ~Falkenstein et al., 1991; Kaiser, Barker, Haenschel, Baldeweg, & Gruzelier, 1997; Leuthold & Sommer, 1999!. Second, sometimes two positive peaks can be discerned in the stimulus-locked ERP associated with incorrect responses: one in the latency range of the classic, stimulus-evoked P3, and one after the incorrect response ~Falkenstein et al., 1991; Leuthold & Sommer, 1999!. A particularly convincing demonstration of two successive P3-like positive components on error trials can be found in ...

Citation Context

...e eyes in an automatic fashion ~e.g., Theeuwes et al., 1998!, correct antisaccade performance requires controlled inhibition of the reflexive saccade towards the abrupt onset cue. A direction error is defined by a saccade in the direction of the cue, even if the eyes are immediately redirected to the opposite location. Despite the task instructions, participants typically make many direction errors in the antisaccade task. Recently, several authors have reported that participants performing an antisaccade task are often not aware of their direction errors when asked immediately after a trial ~Deubel, Mokler, Fischer, & Schneider, 1999; Mokler & Fischer, 1999; for related evidence see Kramer et al., 2000; Theeuwes et al., 1998!. This finding is especially surprising because the unperceived direction errors, just as their perceived counterparts, are typically followed by a corrective saccade of approximately twice the size of the initial error. In Mokler and Fischer, for instance, participants were instructed to look to the opposite side of an abrupt onset cue that was presented 4 deg either to the left or to the right from a central 754 S. Nieuwenhuis et al. fixation point. At the end of each trial, they were to indicate, b...

Citation Context

... from the abrupt onset cue as fast as they could. One second after cue onset, a cross was presented at the target location. At this point, participants were to push a response button if and only if they thought they had moved their eyes in the direction of the cue. To increase the proportion of direction errors, the task design included the following features. First, saccades were required in both the horizontal and the vertical dimension. Increasing the number of possible cue locations from two to four decreases antisaccade performance when locations are positioned along two orthogonal axes ~Delaney & Roberts, 1999!. Second, a gap of 200 ms was introduced between fixation point offset and cue onset. This feature is well known to increase error rates in the antisaccade task ~e.g., Munoz, Broughton, Goldring, & Armstrong, 1998!. A third feature included to increase the error rates was the use of a precue ~in approximately 50% of the trials, to prevent habituation; e.g., Fischer & Weber, 1996!, validly indicating the target location on each presentation.1 Thus, the antisaccade paradigm permitted the study of errorrelated brain activity in an experimental setting in which ~a! participants were always aware ...

Citation Context

...ernstein et al., 1995; Scheffers et al., 1996; Van’t Ent & Apkarian, 1999; but see Gehring et al., 1993!. The second type of evidence comes from studies showing that the Ne amplitude is smaller under circumstances that may be expected to affect the quality of perceptual processing. These circumstances include experimental settings in which participants have to respond under time pressure ~Falkenstein, Hohnsbein, Hoormann, & Blanke, 1990; see also Falkenstein et al., 2000!, have been deprived of sleep ~Scheffers, Humphrey, Stanny, Kramer, & Coles, 1999!, or are presented with degraded stimuli ~Scheffers & Coles, 2000!. The argument is that under these circumstances participants are likely to have a compromised representation of the response required by the stimulus. This, in turn, reduces the mismatch with the representation of the actual response in case of an error. One previous study has paid attention to the relation between the Ne and participants’ confidence in the accuracy of their response ~Scheffers & Coles, 2000!. In this study, participants performed an Eriksen flankers task in which they were required to respond to the identity of one of two briefly presented target letters ~H or S!. The targe...