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Impaired error awareness and anterior cingulate cortex hypoactivity in chronic cannabis users.

Hester R, Nestor L, Garavan H - Neuropsychopharmacology (2009)

Bottom Line: Drug abuse and other psychiatric conditions (eg, schizophrenia) have been associated with a diminished neural response to errors, particularly in the anterior cingulate cortex (ACC) thought critical to error processing.A diminished capacity for detecting errors has been linked to clinical symptoms including the loss of insight, delusions, and perseverative behavior.These difficulties are consistent with earlier reports of hypoactivity in the neural systems underlying cognitive control and the monitoring of interoceptive awareness in chronic drug users, and highlight the potential relationship between cognitive dysfunction and behavioral deficits that have the potential to contribute to the maintenance of drug abuse.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Melbourne, Melbourne, Victoria, Australia. hesterr@unimelb.edu.au

ABSTRACT
Drug abuse and other psychiatric conditions (eg, schizophrenia) have been associated with a diminished neural response to errors, particularly in the anterior cingulate cortex (ACC) thought critical to error processing. A diminished capacity for detecting errors has been linked to clinical symptoms including the loss of insight, delusions, and perseverative behavior. A total of 16 active chronic cannabis users and 16 control participants were administered a Go/No-go response inhibition task during event-related fMRI data collection. The task provides measures of inhibitory control and error awareness. Cannabis users' inhibitory control performance was equivalent to that of the control group, but the former showed a significant deficit in awareness of commission errors. Cannabis users showed a diminished capacity for monitoring their behavior that was associated with hypoactivity in the ACC and right insula. In addition, increased levels of hypoactivity in both the ACC and right insula regions were significantly correlated with error-awareness rates in the cannabis group (but not controls). These difficulties are consistent with earlier reports of hypoactivity in the neural systems underlying cognitive control and the monitoring of interoceptive awareness in chronic drug users, and highlight the potential relationship between cognitive dysfunction and behavioral deficits that have the potential to contribute to the maintenance of drug abuse.

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Related in: MedlinePlus

The Error Awareness TaskThe EAT presents a serial stream of single colour words in congruent fonts, with the word presented for 900ms followed by a 600ms inter-stimulus interval. Participants were trained to respond to each of the words with a single ‘Go trial’ button press, and withhold this response when either of two different circumstances arose. The first was if the same word was presented on two consecutive trials (Repeat No-go), and the second was if the word and font of the word did not match (Stroop No-go). To indicate ‘error awareness’ participants were trained to press the go-trial button twice on the trial following any commission errors.
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Figure 1: The Error Awareness TaskThe EAT presents a serial stream of single colour words in congruent fonts, with the word presented for 900ms followed by a 600ms inter-stimulus interval. Participants were trained to respond to each of the words with a single ‘Go trial’ button press, and withhold this response when either of two different circumstances arose. The first was if the same word was presented on two consecutive trials (Repeat No-go), and the second was if the word and font of the word did not match (Stroop No-go). To indicate ‘error awareness’ participants were trained to press the go-trial button twice on the trial following any commission errors.

Mentions: To examine conscious recognition of errors we administered the Error Awareness Task (EAT) (see Figure 1) (Hester et al, 2005), a motor Go/No-go response inhibition task in which subjects make errors of commission of which they are aware (Aware errors), or unaware (Unaware errors). The EAT presents a serial stream of single colour words in congruent fonts, with the word presented for 900ms followed by a 600ms inter-stimulus interval. Participants were trained to respond to each of the words with a single ‘Go trial’ button press, and withhold this response when either of two different circumstances arose. The first was if the same word was presented on two consecutive trials (Repeat No-go), and the second was if the word and font of the word did not match (Stroop No-go). By having competing types of response inhibition rules we aimed to vary the strength of stimulus-response relationships, whereby representations of rules competitively suppress one another such that the more prepotent rule would suppress the weaker rule and so produce a significant number of errors, a small proportion of which may go unnoticed due to focusing primarily on the prepotent rule. In particular, we aimed to capitalise on the overlearned human behaviour of reading the word, rather than the colour of the letters (the Stroop effect), and so predispose participants to monitor for the Repeat, rather than the Stroop, No-go’s. To indicate ‘error awareness’ participants were trained to press the go-trial button twice on the trial following any commission errors.


Impaired error awareness and anterior cingulate cortex hypoactivity in chronic cannabis users.

Hester R, Nestor L, Garavan H - Neuropsychopharmacology (2009)

The Error Awareness TaskThe EAT presents a serial stream of single colour words in congruent fonts, with the word presented for 900ms followed by a 600ms inter-stimulus interval. Participants were trained to respond to each of the words with a single ‘Go trial’ button press, and withhold this response when either of two different circumstances arose. The first was if the same word was presented on two consecutive trials (Repeat No-go), and the second was if the word and font of the word did not match (Stroop No-go). To indicate ‘error awareness’ participants were trained to press the go-trial button twice on the trial following any commission errors.
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Related In: Results  -  Collection

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Figure 1: The Error Awareness TaskThe EAT presents a serial stream of single colour words in congruent fonts, with the word presented for 900ms followed by a 600ms inter-stimulus interval. Participants were trained to respond to each of the words with a single ‘Go trial’ button press, and withhold this response when either of two different circumstances arose. The first was if the same word was presented on two consecutive trials (Repeat No-go), and the second was if the word and font of the word did not match (Stroop No-go). To indicate ‘error awareness’ participants were trained to press the go-trial button twice on the trial following any commission errors.
Mentions: To examine conscious recognition of errors we administered the Error Awareness Task (EAT) (see Figure 1) (Hester et al, 2005), a motor Go/No-go response inhibition task in which subjects make errors of commission of which they are aware (Aware errors), or unaware (Unaware errors). The EAT presents a serial stream of single colour words in congruent fonts, with the word presented for 900ms followed by a 600ms inter-stimulus interval. Participants were trained to respond to each of the words with a single ‘Go trial’ button press, and withhold this response when either of two different circumstances arose. The first was if the same word was presented on two consecutive trials (Repeat No-go), and the second was if the word and font of the word did not match (Stroop No-go). By having competing types of response inhibition rules we aimed to vary the strength of stimulus-response relationships, whereby representations of rules competitively suppress one another such that the more prepotent rule would suppress the weaker rule and so produce a significant number of errors, a small proportion of which may go unnoticed due to focusing primarily on the prepotent rule. In particular, we aimed to capitalise on the overlearned human behaviour of reading the word, rather than the colour of the letters (the Stroop effect), and so predispose participants to monitor for the Repeat, rather than the Stroop, No-go’s. To indicate ‘error awareness’ participants were trained to press the go-trial button twice on the trial following any commission errors.

Bottom Line: Drug abuse and other psychiatric conditions (eg, schizophrenia) have been associated with a diminished neural response to errors, particularly in the anterior cingulate cortex (ACC) thought critical to error processing.A diminished capacity for detecting errors has been linked to clinical symptoms including the loss of insight, delusions, and perseverative behavior.These difficulties are consistent with earlier reports of hypoactivity in the neural systems underlying cognitive control and the monitoring of interoceptive awareness in chronic drug users, and highlight the potential relationship between cognitive dysfunction and behavioral deficits that have the potential to contribute to the maintenance of drug abuse.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Melbourne, Melbourne, Victoria, Australia. hesterr@unimelb.edu.au

ABSTRACT
Drug abuse and other psychiatric conditions (eg, schizophrenia) have been associated with a diminished neural response to errors, particularly in the anterior cingulate cortex (ACC) thought critical to error processing. A diminished capacity for detecting errors has been linked to clinical symptoms including the loss of insight, delusions, and perseverative behavior. A total of 16 active chronic cannabis users and 16 control participants were administered a Go/No-go response inhibition task during event-related fMRI data collection. The task provides measures of inhibitory control and error awareness. Cannabis users' inhibitory control performance was equivalent to that of the control group, but the former showed a significant deficit in awareness of commission errors. Cannabis users showed a diminished capacity for monitoring their behavior that was associated with hypoactivity in the ACC and right insula. In addition, increased levels of hypoactivity in both the ACC and right insula regions were significantly correlated with error-awareness rates in the cannabis group (but not controls). These difficulties are consistent with earlier reports of hypoactivity in the neural systems underlying cognitive control and the monitoring of interoceptive awareness in chronic drug users, and highlight the potential relationship between cognitive dysfunction and behavioral deficits that have the potential to contribute to the maintenance of drug abuse.

Show MeSH
Related in: MedlinePlus