Errors create reactions that define our behavior as they get registered in our brain for processing. It affects our behavior with perceptions followed by a conscious effort to correct them or slows down so as not to risk them again. The brain controls the recognition and response to errors in people who make them.
Mistakes and the Brain
The actual brain tissue that perceives mistakes and controls responses to them have not been identified yet. Though knowing this is important with respect to medicines and certain conditions of the brain called Obsessive-Compulsive Disorder (OCD).
Scientists have observed that certain portions of the brain are said to be overactive in people with cases of OCD. This leads to their perception of error in the things they do on a daily basis which causes the repetitive pathological errors that affect behavioral patterns ultimately affecting their lives.
Certain other conditions are identified by the reduced ability to detect and respond to the errors. These conditions include schizophrenia and possibly some other, similar psychiatric disorders
The error processing region is believed to be located in the Medial Frontal Cortex (MFC) which houses the motor areas of the brain and is related to error processing. These areas are believed to be associated with impulses that aid in the manipulation of the environment and the coordination of the actions that facilitate this.
Error Recognition in the MFC
The MFC and the motor regions are broadly associated with error recognition through studies based on electroencephalography (EEG) data. This non-invasive technique has helped in the detection of a particular brain activity identified with the error in the course of a task.
Direct implantations of the brain cannot be adopted for just one particular study and would not be ethical. However, a group of researchers working at the California Institute of Technology and Cedars-Sinai Medical Center in Los Angeles devised a much more acceptable and fortuitous opportunity to study MFC and its motor connections in this regard.
A group of patients who had consented to temporary electrode implantation in certain brain regions allowing the study and to model severe epilepsy they were suffering from, was the source of inspiration for the study. This was to devise long-term treatment plans for them. Epilepsy is a condition that may involve the frontal and motor cortices, but not error-recognition or processing.
Therefore, the Caltech/Cedars-Sinai group, led by Dr. Adam Mamelak, a professor of neurosurgery at Cedars-Sinai, secured consent from the same group of patients to perform error-recognition neurological tests while the electrodes were used for the other test.
The Discovery of Error Neurons
The participants completed the Stroop test. The basic goal of the Stroop test is to call out the colors in which the words are printed, and not the color names which formed the readable text. Failing which has been associated with EEG recordings indicating error-recognition neurons (ERNs) in the past.
The Caltech/Cedars-Sinai team found that ERNs were indeed reproducibly evinced in response to ‘misses’ in the course of the Stroop tests.
The researchers were able to use the electrode data not merely to trace the ERNs to certain regions of the MFC and the pre-supplemental motor area (pSMA), but to spell out the single neurons associated with the regions too.
These neurons found in the dorsal anterior cingulate cortex (dACC) and pSMA were designated ‘error neurons’ by the team. These neurons were found to fire first in the pSMA in response to a Stroop-test miss, and then in the dACC about 50 milliseconds later.
This possibly suggests that the motor-related ‘error neurons’ are the first to ‘realize’ that an error-related behavior has been committed, which is then ‘logged’ by the dACC neurons. This could be done to modulate or refine future behavioral impulses so that they may not occur again in the future. Such a possibility is correlated by the additional detection of ‘error-history’ neurons, which were also located in the dACC. Their activity, which increased in response to error-neuron firing, was found to predict the behavioral response of post-error slowing, as the team analyzed their data.
These potentially important findings may now guide the future directions of research into treatments for conditions such as OCD. The team has published this research in the Cell Press journal, Neuron.
The researchers involved in the study believe that their work would enhance the understanding of relevant brain processes such as memory, cognition and behavioral self-regulation in certain situations and would form the prototype for future studies.