INACTIVATION OF DORSOLATERAL PREFRONTAL CORTEX INCREASES ANXIETY BEHAVIORS IN THE RHESUS MONKEY
Document Type
Presentation
Start Date
22-10-2010 10:45 AM
End Date
22-10-2010 12:00 PM
Description
Activity within the prefrontal cortex has long been suspected of modulating affect. More than 150 years ago, Phineas Cage was transformed from a mild-manner, generous foreman of a railroad construction crew into an irritable, sociopath after an iron rod passed through his skull, selectively damaging his frontal lobes. In the 1940's and 1950's, thousands of frontal lobotomies were done to treat mental disorders because of the profound effects these surgeries had on increasing docility and passivity. It is now understood that the prefrontal cortical area consists of a complicated network that regulates affect. The recent application of high frequency stimulation (HFS) to treat depression by inactivating the subgenual cingulate has raised interest in understanding this network. Here we report initial results on behavior changes associated with reversible inactivation of the dorsolateral prefrontal cortex (DLPF) using HFS. A single female monkey underwent surgery to implant stimulating electrodes in a number of prefrontal areas. Following recovery, baseline behavior was assessed with daily, 1 hour video recordings (n=13). HFS was applied at various intensities (n=11) and behavior assessed over a 1 hour period. Behavior was scored every second and forced into 1 of 12 categories. Our results indicate stimulation induced behaviors rarely seen in baseline and altered the frequency of others. The observed changes in behavior were also reversible, the levels returning to baseline after HFS. In particular, anxiety behaviors, such as grooming and scratching, increased significantly. Whereas these results are encouraging, it should be noted that 1) the effects appear sensitive to the time of day, 2) because other areas of the prefrontal cortex have not been inactivated, it is uncertain if the effects observed are selective for only DLPF, and 3) these are observations from one monkey. Because HFS is reversible and minimally invasive, it is potentially a powerful tool for experimentally assessing localization of function.
Recommended Citation
Hutcherson, Lori; Richter, E. O.; and Weyand, T. G., "INACTIVATION OF DORSOLATERAL PREFRONTAL CORTEX INCREASES ANXIETY BEHAVIORS IN THE RHESUS MONKEY" (2010). Dr. Joseph M. Moerschbaecher, III Graduate Research Day. 11.
https://digitalscholar.lsuhsc.edu/grad_rs/2010/poster1/11
INACTIVATION OF DORSOLATERAL PREFRONTAL CORTEX INCREASES ANXIETY BEHAVIORS IN THE RHESUS MONKEY
Activity within the prefrontal cortex has long been suspected of modulating affect. More than 150 years ago, Phineas Cage was transformed from a mild-manner, generous foreman of a railroad construction crew into an irritable, sociopath after an iron rod passed through his skull, selectively damaging his frontal lobes. In the 1940's and 1950's, thousands of frontal lobotomies were done to treat mental disorders because of the profound effects these surgeries had on increasing docility and passivity. It is now understood that the prefrontal cortical area consists of a complicated network that regulates affect. The recent application of high frequency stimulation (HFS) to treat depression by inactivating the subgenual cingulate has raised interest in understanding this network. Here we report initial results on behavior changes associated with reversible inactivation of the dorsolateral prefrontal cortex (DLPF) using HFS. A single female monkey underwent surgery to implant stimulating electrodes in a number of prefrontal areas. Following recovery, baseline behavior was assessed with daily, 1 hour video recordings (n=13). HFS was applied at various intensities (n=11) and behavior assessed over a 1 hour period. Behavior was scored every second and forced into 1 of 12 categories. Our results indicate stimulation induced behaviors rarely seen in baseline and altered the frequency of others. The observed changes in behavior were also reversible, the levels returning to baseline after HFS. In particular, anxiety behaviors, such as grooming and scratching, increased significantly. Whereas these results are encouraging, it should be noted that 1) the effects appear sensitive to the time of day, 2) because other areas of the prefrontal cortex have not been inactivated, it is uncertain if the effects observed are selective for only DLPF, and 3) these are observations from one monkey. Because HFS is reversible and minimally invasive, it is potentially a powerful tool for experimentally assessing localization of function.