Error-related negativity
Encyclopedia
Error-related negativity (ERN), (sometimes referred to as the Ne), is a component of an event-related potential
(ERP). ERPs are electrical activity in the brain as measured through electroencephalography
(EEG) and time-locked to an external event (e.g., presentation of a visual stimulus or an error of commission). A robust ERN component is observed after errors are committed during various choice tasks, even when the participant is not explicitly aware of making the error; however, in the case of unconscious errors the ERN is reduced (Niewenhuis, Ridderinkhof, Blom, Band, & Kok, 2001).
), and typically peaks from 80-150 milliseconds (ms) after the erroneous response begins (or 40-80 ms after the onset of electromyographic activity). The ERN is the largest at frontal and central electrode sites. A typical method for determining the average ERN amplitude for an individual involves calculating the peak-to-peak difference in voltage
between the average of the most negative peaks 1-150 ms after response onset, and the average amplitude of positive peaks 100-0 ms before response onset. For optimal resolution of the signal, reference electrodes are typically placed behind both ears using either hardware or arithmetically linked mastoid electrodes.
.
A standard Flanker task involves discerning the central “target” letter from a string of distracting “flanker” letters which surround it. For example, congruous letter strings such as “SSSSS” or “HHHHH” and incongruous letter strings such as “HHSHH” or “SSHSS” may be presented on a computer screen. Each target letter would be assigned a key stroke response on a keyboard, such as “S” = right shift key and “H” = left shift key. Presentation of each letter string is brief, generally less than 100 ms, and central on the screen. Participants have approximately 2000 ms to respond before the next presentation.
The most simple Go/NoGo tasks involve assigning a property of discernment to responding “Go” or not responding “NoGo.” For example, again congruous letter strings such as “SSSSS” or “HHHHH” and incongruous letter strings such as “HHSHH” or “SSHSS” may be presented on a computer screen. The participant could be instructed to respond by pressing the space bar, only for congruous strings, and to not respond when presented with incongruous letter strings. More complicated Go/NoGo tasks are usually created when the ERN is the component of interest however, because in order to observe the robust negativity errors must be made.
The classic Stroop
paradigm involves a color-word task. Color words such as “red, yellow, orange, green” are presented centrally on a computer screen either in a color congruent with the word, (“red” in the color red) or in a color incongruent with the word (“red” in the color yellow). Participants may be asked to verbalize the color each word is written in. Incongruent and congruent presentations of the words can be manipulated to different rates, such as 25/75, 50/50, 30/70 etc.
(ACC) area of the brain. This conclusion is supported by fMRI, and brain lesion research, as well as dipole source modeling. The Dorsolateral Prefrontal Cortex
(DLPFC) may also be involved in the generation of the ERN to some degree, and it has been found that persons with higher levels of "absent-mindedness" have their ERN sourced more from that region.
There is some debate within the field about what the ERN reflects (see especially Burle, et al.) Some researchers maintain that the ERN is generated during the detection of or response to errors. Others argue that the ERN is generated by a comparison process or a conflict monitoring system, and not specific to errors.
indicating that events have gone worse than expected. In this framework it is common to measure both the rERN and the fERN as the difference in voltage between correct and incorrect responses and feedback, respectively.
and the Pe has a dipole in the posterior cingulate cortex. The Pe amplitude reflects the perception of the error, meaning with more awareness of the error, the amplitude of the Pe is larger. Falkenstein and colleagues (2000) have shown that the Pe is elicited on uncorrected trials and false alarm trials, suggesting it is not directly related to error correction. It thus seems to be related to error monitoring, albeit with different neural and cognitive roots from the error-related processing reflected in the Ne.
If the Pe reflects conscious error processing, then it might be expected to be different for people with deficits in conflict monitoring, such as ADHD and OCD. Whether this is true remains controversial. Some studies do indicate these conditions are associated with different Pe responses, whereas other studies have not replicated those findings. The Pe has also been used to evaluate error processing in patients with severe brain traumatic injury. In a study using a variation of the Stroop task
, patients with severe traumatic brain injury associated with deficits in error processing were found to show a significantly smaller Pe on error trials when compared against the healthy controls.
Event-related potential
An event-related potential is any measured brain response that is directly the result of a thought or perception. More formally, it is any stereotyped electrophysiological response to an internal or external stimulus....
(ERP). ERPs are electrical activity in the brain as measured through electroencephalography
Electroencephalography
Electroencephalography is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain...
(EEG) and time-locked to an external event (e.g., presentation of a visual stimulus or an error of commission). A robust ERN component is observed after errors are committed during various choice tasks, even when the participant is not explicitly aware of making the error; however, in the case of unconscious errors the ERN is reduced (Niewenhuis, Ridderinkhof, Blom, Band, & Kok, 2001).
History
The ERN was first discovered in 1990 by two independent research teams; Michael Falkenstein, J. Hohnsbein, J. Joormann, & L. Blanke (1990) at the Institute for Work Physiology and Neurophysiology in Dortmund, Germany (who called it the “Ne”), and W.J. “Bill” Gehring, D.E. Meyer & E. Donchin (1990) at the University of Michigan, USA. The ERN was observed in response to errors committed by study participants during simple choice response tasks.Component Characteristics
The ERN is a sharp negative going signal which begins about the same time an incorrect motor response begins, (response locked event-related potentialEvent-related potential
An event-related potential is any measured brain response that is directly the result of a thought or perception. More formally, it is any stereotyped electrophysiological response to an internal or external stimulus....
), and typically peaks from 80-150 milliseconds (ms) after the erroneous response begins (or 40-80 ms after the onset of electromyographic activity). The ERN is the largest at frontal and central electrode sites. A typical method for determining the average ERN amplitude for an individual involves calculating the peak-to-peak difference in voltage
Voltage
Voltage, otherwise known as electrical potential difference or electric tension is the difference in electric potential between two points — or the difference in electric potential energy per unit charge between two points...
between the average of the most negative peaks 1-150 ms after response onset, and the average amplitude of positive peaks 100-0 ms before response onset. For optimal resolution of the signal, reference electrodes are typically placed behind both ears using either hardware or arithmetically linked mastoid electrodes.
Main Paradigms
Any paradigm in which mistakes are made during motor responses can be used to measure the ERN. The most important feature of any ERN paradigm is obtaining a sufficient number of errors in the participant's responses. Early experiments identifying the component used a variety of techniques, including word and tone identification, and categorical discrimination (e.g. are the following an animal?). . However, the majority of experimental paradigms that elicit ERN deflections have been a variant on the Eriksen “Flanker”, and “Go/NoGo,”. In addition to responses with the hands, the ERN can also be measured in paradigms where the task is performed with the feet or with vocal responses as in the Stroop paradigmStroop effect
Purple Blue Purple----Blue Purple RedGreen Purple Green----the Stroop effect refers to the fact that naming the color of the first set of words is easier and quicker than the second....
.
A standard Flanker task involves discerning the central “target” letter from a string of distracting “flanker” letters which surround it. For example, congruous letter strings such as “SSSSS” or “HHHHH” and incongruous letter strings such as “HHSHH” or “SSHSS” may be presented on a computer screen. Each target letter would be assigned a key stroke response on a keyboard, such as “S” = right shift key and “H” = left shift key. Presentation of each letter string is brief, generally less than 100 ms, and central on the screen. Participants have approximately 2000 ms to respond before the next presentation.
The most simple Go/NoGo tasks involve assigning a property of discernment to responding “Go” or not responding “NoGo.” For example, again congruous letter strings such as “SSSSS” or “HHHHH” and incongruous letter strings such as “HHSHH” or “SSHSS” may be presented on a computer screen. The participant could be instructed to respond by pressing the space bar, only for congruous strings, and to not respond when presented with incongruous letter strings. More complicated Go/NoGo tasks are usually created when the ERN is the component of interest however, because in order to observe the robust negativity errors must be made.
The classic Stroop
Stroop effect
Purple Blue Purple----Blue Purple RedGreen Purple Green----the Stroop effect refers to the fact that naming the color of the first set of words is easier and quicker than the second....
paradigm involves a color-word task. Color words such as “red, yellow, orange, green” are presented centrally on a computer screen either in a color congruent with the word, (“red” in the color red) or in a color incongruent with the word (“red” in the color yellow). Participants may be asked to verbalize the color each word is written in. Incongruent and congruent presentations of the words can be manipulated to different rates, such as 25/75, 50/50, 30/70 etc.
Functional Sensitivity
The amplitude of the ERN is sensitive to the intent and motivation of participants. When a participant is instructed to strive for accuracy in responses, observed amplitudes are typically larger than when participants are instructed to strive for speed. Monetary incentives typically result in larger amplitudes as well. Latency of the ERN peak amplitude can also vary between subjects, and does so reliably in special populations such as those diagnosed with ADHD, who show shorter latencies. Participants with clinically diagnosed Obsessive Compulsive Disorder have exhibited ERN deflections with increased amplitude, prolonged latency, and a more posterior topography compared to clinically normal participants. ERN latency has been manipulated through rapid feedback, wherein participants who received rapid feedback regarding the incorrect response subsequently showed shorter ERN peak latencies.Theory/Source
Although it is impossible to determine where in the brain an ERP signal originated, extensive empirical research indicates that the ERN is most likely generated in the Anterior cingulate cortexAnterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
(ACC) area of the brain. This conclusion is supported by fMRI, and brain lesion research, as well as dipole source modeling. The Dorsolateral Prefrontal Cortex
Dorsolateral prefrontal cortex
The dorsolateral prefrontal cortex , according to a more restricted definition, is roughly equivalent to Brodmann areas 9 and 46. According to a broader definition DL-PFC consists of the lateral portions of Brodmann areas 9 – 12, of areas 45, 46, and the superior part of area 47. These regions...
(DLPFC) may also be involved in the generation of the ERN to some degree, and it has been found that persons with higher levels of "absent-mindedness" have their ERN sourced more from that region.
There is some debate within the field about what the ERN reflects (see especially Burle, et al.) Some researchers maintain that the ERN is generated during the detection of or response to errors. Others argue that the ERN is generated by a comparison process or a conflict monitoring system, and not specific to errors.
Feedback Error-related Negativity
A stimulus locked event-related potential is also observed following the presentation of negative feedback stimuli in a cognitive task indicating the outcome of a response, often referred to as the feedback ERN (fERN). This has led some researchers to extend the error-detection account of the response ERN (rERN) to an generic error detection system. This position has been elaborated into a reinforcement learning account of the ERN, arguing that both the rERN and the fERN are products of prediction error signals carried by the dopamine system arriving in the anterior cingulate cortexAnterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
indicating that events have gone worse than expected. In this framework it is common to measure both the rERN and the fERN as the difference in voltage between correct and incorrect responses and feedback, respectively.
Clinical Applications
Debates about psychiatric disorders often become “chicken and egg” conundrums. The ERN has been proposed as a potential arbitrator of this argument. A body of empirical research has shown that the ERN reflects a “trait” level difference in individual error processing; especially concerning anxiety, rather than a “state” level difference. For example; most people who experience depression do not feel depressed all of the time. Instead, they have periods of depressive “states” which may be minor and unique to an extreme situation such death of a loved one, loss of employment, or major injury. However a person who has a depressive “trait” will have experienced more than one minor depressive “state” and usually at least one major depressive state, any of which may not be unique to an obviously extreme situation. Scientists are exploring the use of the ERN and other ERP signals in identifying people at risk for psychiatric disorders in hopes of implementing early interventions. People with addictive behaviors such as smoking, alcoholism, and substance abuse have also shown differential ERN responses compared to individuals without the same addictive behavior.Error-related positivity
The ERN is often followed by a positivity, known as the error-related positivity or Pe. The Pe is a positive deflection with a centro-parietal distribution. When elicited, the Pe can occur 200-500ms after making an incorrect response, following the error negativity (Ne, ERN), but is not evident on all error trials. In particular, the Pe is dependent on awareness or ability to detect errors. Additionally, Vocat et al. (2008) established the Ne and Pe not only have different topographical distributions, but have different generators. Source localization indicates that the Ne has a dipole in the anterior cingulate cortexAnterior cingulate cortex
The anterior cingulate cortex is the frontal part of the cingulate cortex, that resembles a "collar" form around the corpus callosum, the fibrous bundle that relays neural signals between the right and left cerebral hemispheres of the brain...
and the Pe has a dipole in the posterior cingulate cortex. The Pe amplitude reflects the perception of the error, meaning with more awareness of the error, the amplitude of the Pe is larger. Falkenstein and colleagues (2000) have shown that the Pe is elicited on uncorrected trials and false alarm trials, suggesting it is not directly related to error correction. It thus seems to be related to error monitoring, albeit with different neural and cognitive roots from the error-related processing reflected in the Ne.
If the Pe reflects conscious error processing, then it might be expected to be different for people with deficits in conflict monitoring, such as ADHD and OCD. Whether this is true remains controversial. Some studies do indicate these conditions are associated with different Pe responses, whereas other studies have not replicated those findings. The Pe has also been used to evaluate error processing in patients with severe brain traumatic injury. In a study using a variation of the Stroop task
Stroop effect
Purple Blue Purple----Blue Purple RedGreen Purple Green----the Stroop effect refers to the fact that naming the color of the first set of words is easier and quicker than the second....
, patients with severe traumatic brain injury associated with deficits in error processing were found to show a significantly smaller Pe on error trials when compared against the healthy controls.
See also
- Somatosensory evoked potentialSomatosensory Evoked PotentialSomatosensory Evoked Potentials are a useful, noninvasive means of assessing somatosensory system functioning. By combining SEP recordings at different levels of the somatosensory pathways, it is possible to assess the transmission of the afferent volley from the periphery up to the cortex...
- C1 and P1C1 & P1 (Neuroscience)The C1 and P1 are two human scalp-recorded event-related brain potential components, collected by means of a technique called electroencephalography . The C1 is named so because it was the first component in a series of components found to respond to visual stimuli when it was first discovered...
- Visual N1Visual N1The Visual N1 is a visual evoked potential, a type of event-related electrical potential , that is produced in the brain and recorded on the scalp. The N1 is so named to reflect the polarity and typical timing of the component. The "N" indicates that the polarity of the component is negative with...
- Mismatch negativityMismatch negativityThe mismatch negativity or mismatch field is a component of the event-related potential to an odd stimulus in a sequence of stimuli. It arises from electrical activity in the brain and is studied within the field of cognitive neuroscience and psychology. It can occur in any sensory system, but...
- N100
- N200N200 (neuroscience)The N200, or N2, is an event-related potential component. An ERP can be monitored using a non-invasive electroencephalography cap that is fitted over the scalp on human subjects...
- N2pcN2pcN2pc refers to an ERP component linked to selective attention. The N2pc appears over visual cortex contralateral to the location in space to which subjects are attending; if subjects pay attention to the left side of the visual field, the N2pc appears in the right hemisphere of the brain, and...
- N170N170The N170 is a component of the event-related potential that reflects the neural processing of faces.When potentials evoked by images of faces are compared to those elicited by other visual stimuli, the former show increased negativity 130-200 ms after stimulus presentation...
- P200P200In neuroscience, the visual P200 or P2 is a waveform component or feature of the event-related potential measured at the human scalp. Like other potential changes measurable from the scalp, this effect is believed to reflect the post-synaptic activity of a specific neural process...
- N400
- P300 (neuroscience)P300 (neuroscience)The P300 wave is an event related potential elicited by infrequent, task-relevant stimuli. It is considered to be an endogenous potential as its occurrence links not to the physical attributes of a stimulus but to a person's reaction to the stimulus. More specifically, the P300 is thought to...
- P3aP3aThe P3a, or novelty P3, is a component of time-locked signals known as event-related potentials . The P3a is a positive-going scalp-recorded brain potential that has a maximum amplitude over frontal/central electrode sites with a peak latency falling in the range of 250-280 ms...
- P3bP3bThe P3b is a subcomponent of the P300, an event-related potential component that can be observed in human scalp recordings of brain electrical activity...
- Late Positive ComponentLate Positive ComponentThe LPC is a positive-going event-related brain potential component that has been important in studies of explicit recognition memory...
- Difference due to MemoryDifference due to MemoryDifference due to Memory indexes differences in neural activity during the study phase of an experiment for items that subsequently are remembered compared to items that are later forgotten...
- Contingent negative variationContingent negative variationThe contingent negative variation was one of the first event-related potential components to be described. The CNV component was first described by Dr. W. Grey Walter and colleagues in an article published in Nature in 1964...
- BereitschaftspotentialBereitschaftspotentialIn neurology, the Bereitschaftspotential or BP , also called the pre-motor potential or readiness potential , is a measure of activity in the motor cortex of the brain leading up to voluntary muscle movement. The BP is a manifestation of cortical contribution to the pre-motor planning of volitional...
- Lateralized readiness potentialLateralized readiness potentialIn neuroscience, the lateralized readiness potential is an event-related brain potential, or increase in electrical activity at the surface of the brain, that is thought to reflect the preparation of motor activity on a certain side of the body; in other words, it is a spike in the electrical...
- Early left anterior negativityEarly left anterior negativityThe early left anterior negativity is an event-related potential in electroencephalography , or component of brain activity that occurs in response to a certain kind of stimulus...
- P600P600The P600 is an event-related potential , or peak in electrical brain activity measured by electroencephalography . It is a language-relevant ERP and is thought to be elicited by hearing or reading grammatical errors and other syntactic anomalies...