How does our brain manage to control impulses and stop us from screaming or undressing in public? Current study reveals key mechanisms
To put it simply, an inhibitory reaction in the brain is like a “brake system” in the brain. Imagine you have an impulse or idea to do something, such as screaming in a library, pulling down your pants on the subway, or eating a candy before dinner. Your brain uses inhibitory responses to stop you and say, “Wait, maybe it’s not a good idea to do that right now.” It’s a crucial part of how we control our behavior and make decisions in different ways consider situations to be most appropriate or appropriate.
In a study published in the journal Psychoradiology, researchers from the University of Hong Kong and the University of Electronic Science and Technology of China have identified the leader of the inhibitory response: the right inferior frontal gyrus (rIFG), which acts as a crucial regulator in the subcortical Reaction inhibition node, i.e. the reaction of the most emotional and primitive parts of the brain. This inhibitory control circuit is located on the right side of the brain and is connected to many other important parts within it.
The study used dynamic causal modeling (DCM-PEB) and functional MRI on a sample of 250 people to examine inhibitory circuits in the brain. He particularly focused on these parts of the brain: the right inferior frontal gyrus (rIFG), the caudate nucleus (rCau), the globus pallidus (rGP), and the thalamus (rThal). The results showed high connectivity between these areas because when an intrinsic response in this neuronal circuit was inhibited, connections from the rIFG to the rCau and rThal increased with the inhibition of the response.
Additionally, the study found that gender and performance metrics have a significant impact on the functional architecture of the circuit. For example, in females, increased self-inhibition in the rThal and decreased modulation to the GP were observed, while better inhibitory performance was associated with more robust communication from the rThal to the rIFG.
These communication patterns were not reflected in a left-lateralized model, suggesting that the response is asymmetric between hemispheres. Research suggests that different brain processes may mediate behavioral response inhibition between the sexes, particularly in loops in the thalamus.
Hope for mental disorders
People with impulse control difficulties can manifest in different ways and be an aspect of different medical conditions. For example, those affected by attention deficit hyperactivity disorder (ADHD) often act rashly without thinking about the consequences. It is also seen in some individuals with autism spectrum disorders. In behavioral disorders such as oppositional defiant disorder, impulsive and defiant actions can be observed. People with certain personality disorders, such as: People with disabilities, such as borderline personality disorder, may struggle with impulsivity, as may people who struggle with addictions or certain neurological disorders that affect the brain’s impulse regulation.
These insights into the brain’s inhibitory control mechanisms have significant implications for understanding a variety of psychological and neurological disorders characterized by deficits in response inhibition. The study results could serve as a guide for the development of targeted neuromodulation strategies and personalized interventions to address these deficits and improve the treatment and management of such disorders.
REFERENCES
The right inferior frontal gyrus as a central node and effective regulation of the basal ganglia-thalamocortical response inhibition circuit.
Image: Brain activation maps for general response inhibition at the whole brain level (contrast: NoGo > Go; P < 0.05 FWE, maximum level). L, left; R, right. The color bar represents the t-values of the BOLD signal and reflects the significance level of the contrast. CREDIT: Psychoradiology