Connectivity‐based parcellation of the anterior limb of the internal capsule

Abstract

The anterior limb of internal capsule (ALIC) is an important locus of frontal-subcortical fiber tracts involved in cognitive and limbic feedback loops. However, the structural organization of its component fiber tracts remains unclear. Therefore, although the ALIC is a promising target for various neurosurgical procedures for psychiatric disorders, more precise understanding of its organization is required to optimize target localization. Using diffusion tensor imaging (DTI) collected on healthy subjects by the Human Connectome Project (HCP), we generated parcellations of the ALIC by dividing it according to structural connectivity to various frontal regions. We then compared individuals’ parcellations in order to evaluate the ALIC’s structural consistency. All 40 included subjects demonstrated a posterior-superior to anterior-inferior axis of tract organization in the ALIC. Nonetheless, subdivisions of the ALIC were found to vary substantially, as voxels in the average parcellation were accurately assigned for a mean of only 66.2% of subjects. There were, however, some loci of consistency, most notably in the region maximally connected to orbitofrontal cortex. These findings clarify the highly variable organization of the ALIC and may represent a tool for patient-specific targeting of neuromodulation.

Individual white matter bundle trajectories are associated with deep brain stimulation response in obsessive-compulsive disorder

“…Building on psychosurgical lesioning experience [2], DBS is often targeted at ventral capsule/ventral striatum (VC/VS) areas [3], and normalizes pathological hyperconnectivity to the prefrontal cortex (PFC) [4]. At our institute, DBS is applied within the ventral part of the anterior limb of the internal capsule (vALIC) [5], a region which is known for large inter-subject white matter (WM) tracts variability [6,7]. We hypothesized that treatment response could depend on the location of the active contacts with respect to these tracts, which is currently not accounted for in DBS target planning based on anatomical landmarks.…”

White Matter Abnormalities of Auditory Neural Pathway in Sudden Sensorineural Hearing Loss Using Diffusion Spectrum Imaging: Different Findings From Tinnitus

“…Previous studies have reported that the contralateral pathway is more important than the ipsilateral pathway in the processing of auditory stimulation (Khosla et al, 2003;Langers et al, 2005), of which 70-80% from the contralateral side and 20-30% comes from the ipsilateral side. Furthermore, the anterior limb of the internal capsule is believed to be involved in cognitive function, such as decision-making, attention, memory and so on (Nanda et al, 2017). For example, the change of QA value in this area may be related to the psychological problems such as anxiety and depression which often occur in patients with sudden hearing loss (Arslan et al, 2018).…”

Distance to white matter trajectories is associated with treatment response to internal capsule deep brain stimulation in treatment-resistant depression

“…The white matter anatomy of the ALIC has been shown to be well-ordered, but variable along individuals. [11,[14][15][16] It was hypothesized that stimulation of disrupted dopaminergic connections from the ventral tegmental area (VTA) to the nucleus accumbens/striatum might be related to treatment response for TRD. [17] Research based on this hypothesis disentangled two important fiber pathways coursing through the ALIC: the anterior thalamic radiation (ATR), and the superolateral medial forebrain bundle (slMFB) [11].…”