Jordan Grafman, PhD, professor of Physical Medicine and Rehabilitation and of Psychiatry and Behavioral Sciences, co-authored the study published in Nature Medicine.
Damage to particular brain regions can influence addictive behaviors, providing insight into potential therapeutic targets for substance use disorders, according to findings published in Nature Medicine.
“By examining whether damage to selected brain regions in humans can cause changes in addictive behaviors, we provided complementary and novel evidence about brain networks critically involved in addictive behaviors,” said Jordan Grafman, PhD, professor of Medicine Physics and Rehabilitation, of Psychiatry and Behavioral Sciences and co-author of the study; Grafman also directs brain injury research at the Shirley Ryan AbilityLab.
Substance use disorders are considered a public health crisis in the US and internationally; effective treatments are still needed and long-term remission rates remain low. However, previous work had discovered a potential link between damage to specific parts of the brain and repetitive addictive behaviors, specifically reward or pleasure-seeking behaviors.
In the current study, researchers studied two patient cohorts, 67 patients and 62 patients, respectively, who were active smokers at the time of focal brain damage from stroke or traumatic brain injury. They also studied 186 patients with penetrating traumatic brain injury who experienced alcohol addiction.
Some lesions associated with remission of smoking addiction crossed the insula (a) but many others did not (b). Each slice represents a different patient and lesion locations are shown in red.
CT and MRI brain scans of the patients were then used to create diagrams of each lesion location, resulting in a total of 129 brain injuries due to stroke and 186 brain injuries due to penetrating traumatic brain injury . Lesion locations were mapped to a brain atlas, and the functionally connected brain network at each lesion site was determined using data from the human connectome.
The researchers found that the lesions that altered smoking and alcohol addiction behaviors occurred in many different brain locations and were characterized by a specific pattern of brain connectivity. In particular, positive connectivity was observed in regions of the dorsal cingulate (cognition and motor control), lateral prefrontal cortex (cognition), and insular (sensory) regions. Negative connectivity was observed in regions of the prefrontal and medial temporal cortex, which are involved in numerous cognitive functions and object recognition, among other functions.
Brain regions with connectivity profiles similar to those observed in patients in remission were the paracingulate gyrus (cognitive and affective regulation), the left frontal operculum (language), and the medial frontopolar cortex (cognition).
According to the authors, the regions identified may serve as potential sites for targeted therapeutic interventions that could help correct addictive behaviors.
“We have potential target sites for trying to reduce addictive behaviors, and one potential approach is to combine behavioral and cognitive strategies that reduce addictive behaviors with noninvasive brain stimulation, techniques such as transcranial magnetic or electrical stimulation,” Grafman said.
Furthermore, identifying the precise roles of these regions within the identified brain network may highlight which parts of the neural circuits are key to modifying addictive behaviors, allowing for more precise therapeutic targets through a neuromodulation strategy, according to Grafman.
This work was supported by the Academy of Finland (no. 295580), the Finnish Medical Foundation, the Instrumentarium Research Foundation, the Finnish Foundation for Alcohol Studies, and Turku University Hospital (fund HERB).[ad_2]
Source: The location of brain lesions influences addictive behaviors