DBS in the basolateral amygdala improves symptoms of autism and related self-injurious behavior: a case report and hypothesis on the pathogenesis of the disorder

Abstract

We treated a 13-year-old boy for life-threatening self-injurious behavior (SIB) and severe Kanner's autism with deep brain stimulation (DBS) in the amygdaloid complex as well as in the supra-amygdaloid projection system. Two DBS-electrodes were placed in both structures of each hemisphere. The stimulation contacts targeted the paralaminar, the basolateral (BL), the central amygdala as well as the supra-amygdaloid projection system. DBS was applied to each of these structures, but only stimulation of the BL part proved effective in improving SIB and core symptoms of the autism spectrum in the emotional, social, and even cognitive domains over a follow up of now 24 months. These results, which have been gained for the first time in a patient, support hypotheses, according to which the amygdala may be pivotal in the pathogeneses of autism and point to the special relevance of the BL part.

Keywords: amygdala; autism; deep brain stimulation; self-injurious behavior.

Figure 1

Image fusion of post-operation CT (nine months after implantation) with T₁-weighted intraoperative planning MRT visualizing the actual electrode position in axial and coronal planes (displayed image size: 145 × 145 mm). The active contacts are indicated by red lines in the coronal section. (A) The coronal image is re-sliced in order to show the electrode trajectory in the section plane. Arrowheads indicate the trajectories of the supra-amygdaloid electrodes, which are not activated. The active poles on the right electrode are located close to the posterior part of the basolateral amygdaloid nucleus (Contact 0 and 1). The active pole on the left electrode is positioned in the center of the basolateral nucleus. (B) Horizontal section through the amygdala of both hemispheres showing the electrodes indicated by arrows in the posterior part of the basolateral nucleus immediately in front of the tip of the temporal horn of the ventricle.

Figure A1

Changes of irritability [Clinical Global Impression Severity Scale (CGI)] and of core symptoms of autism (ADI-R) in the course of treatment. The CGI-Severity Scale according to Guy (1976) is displayed here for addressing the target symptoms of irritability expressed by the patient during the course of treatment. The scale has a range from 1 (normal) to 7 (extremely ill). Time point 0 corresponds to the initial onset of DBS. Arrows indicate substantial changes induced by stopping (week 44) and restarting (week 48) DBS, respectively. After resuming DBS, CGI was constantly rated at 4 (moderately ill). The CGI was measured for the last time 59 weeks after restarting DBS treatment. CGI was determined on the same day when the ADI-R was also assessed. ADI-R is included into this diagram for illustrative purposes.