English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  The Thalamus and the Limbic System: Tracing the Structural Connectivity

Grodd, W., Kumar, V., & Scheffler, K. (2019). The Thalamus and the Limbic System: Tracing the Structural Connectivity. Poster presented at 25th Annual Meeting of the Organization for Human Brain Mapping (OHBM 2019), Roma, Italy.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/21.11116/0000-0003-C5FE-1 Version Permalink: http://hdl.handle.net/21.11116/0000-0004-3FEE-B
Genre: Poster

Files

show Files

Creators

show
hide
 Creators:
Grodd, W1, 2, Author              
Kumar, V1, 2, Author              
Scheffler, K1, 2, Author              
Affiliations:
1Department High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Max Planck Society, ou_1497796              
2Max Planck Institute for Biological Cybernetics, Max Planck Society, ou_1497794              

Content

show
hide
Free keywords: -
 Abstract: Introduction: The limbic system is a phylogenetically old behaviorally defined system that serves as a center for emotions, as it controls anger, fear, and joy and has an influence on sexual behavior, vegetative functions, and memory [1]–[5]. It comprises a collection of tel-, di-, and mesencephalic structures, whose components have increased over time [4], [6]. The previous animal research indicates that the anterior nuclear group of the thalamus (ANT), as well as the Habenula (Hb) and mediodorsal nucleus (MD) each, play a vital role in the limbic circuitry. Accordingly, diffusion imaging data obtained from the Human Connectome Project, and the masks of six (anterodorsal AD, anteromedial AM, anteroventral AV, lateral dorsal LD, habenula Hb, and mediodorsal MD) nuclei served as seed regions for a direct probabilistic tracking to the rest of the brain using diffusion-weighted imaging (DWI) (s. Fig. 1). Methods: Data: The diffusion imaging data of 730 subjects obtained from the Human Connectome Project [7]. The diffusion data were acquired by using a Spin-echo EPI sequence, TR: 5520 ms, TE: 89.5ms, voxel size: 1.25 mm isotropic, b-values: 1000, 2000, and 3000 s/mm2. For details, see [7], [8]. Data analysis: The whole brain multi-shell reconstruction of the diffusion data were performed using the multi-shell model [9] implemented in bedpostx [10]. Connectivity analysis: The masks of six (anterodorsal AD, anteromedial AM, anteroventral AV, lateral dorsal LD, habenula Hb, and mediodorsal MD) nuclei served as seed regions[11] for a direct probabilistic tracking to the rest of the brain using probtrackx [12]. In the direct diffusion tractography, all streamlines passing through other thalamic nuclei were excluded to depict only directly routed connections to the ipsilateral cortex. The resulting tractograms were each normalized, and in the last step, the group fixed effect maps were computed (s. Fig 2). Results: The results revealed that the ANT nuclei are parts of the limbic and memory system as they mainly connect via mammillary tract, mammillary body, anterior commissure, fornix, and retrosplenial cortices to the hippocampus, amygdala, medio-temporal, orbito-frontal and occipital cortices [13]–[15]. Furthermore, the ANT nuclei showed with different extent connections to the mesencephalon and brainstem: a pattern rarely described in experimental findings (s. Fig. 2). The habenula – usually defined as part of the epithalamus – was closely connected to the tectum opticum and seems to serve as a neuroanatomical hub between the visual and limbic system, brainstem and cerebellum [16]–[18]. Finally, in contrast to experimental findings with tracer studies, the direct connections of MD were mainly confined to the brainstem, while the indirect MD fibers form a broad pathway connecting the hippocampus and medio-temporal areas with the mediofrontal cortex. Conclusions: The study presents a first approach in human to examine and verify the structural connectivity between diverse components of the limbic system and selected thalamic nuclei in a whole brain approach. Despite methodological discrepancies between diffusion guided fiber tracking and experimental connectivity studies using ante- and retrograde tracers in animals, we could confirm, that the ANT, Hb, and MD nuclei with different extent connect to major limbic components and with the mesencephalon and brainstem. While ANT nuclei broadly connect the hypothalamus, septal and prefrontal areas via fornix and cingulum with the retrosplenial area and the hippocampus, links the Hb the hypothalamus and orbitofrontal cortices via the stria medullaris and fornix with the tectum and visual cortices. Finally, only indirect MD tracts (i.e., connectivity via other thalamic nuclei) show extensive bilateral connections to the medio-frontal cortex. The determined tracts of the examined six nuclei will be available under https://github.com/vinkrishna/Limbic_Thalamus.

Details

show
hide
Language(s):
 Dates: 2019-06
 Publication Status: Published online
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Method: -
 Identifiers: -
 Degree: -

Event

show
hide
Title: 25th Annual Meeting of the Organization for Human Brain Mapping (OHBM 2019)
Place of Event: Roma, Italy
Start-/End Date: 2019-06-09 - 2019-06-13

Legal Case

show

Project information

show

Source 1

show
hide
Title: 25th Annual Meeting of the Organization for Human Brain Mapping (OHBM 2019)
Source Genre: Proceedings
 Creator(s):
Affiliations:
Publ. Info: -
Pages: - Volume / Issue: - Sequence Number: Th729 Start / End Page: - Identifier: -