Cortical and Subcortical Projections from Granular Insular Cortex Receiving Orofacial Proprioception
Yumi Tsutsumi1, Yoshihisa Tachibana2, Fumihiko Sato1
1Department of Oral Anatomy and Neurobiology, Graduate School of Dentistry, Osaka University, Suita, Osaka 565-0871, Japan.
Neuroscience
|August 6, 2018
Summary
Proprioceptive signals from jaw muscles travel to the insular cortex and then project to sensorimotor and emotional brain regions. This study maps the pathways of jaw-closing muscle spindle (JCMS) proprioception in rats.
Area of Science:
- Neuroscience
- Somatosensation
- Neuroanatomy
Background:
- Jaw-closing muscle spindles (JCMSs) provide proprioceptive feedback.
- Previous research identified JCMS input to the rat's dorsal granular insular cortex (dGIrvs2).
- The downstream pathways from dGIrvs2 remain largely uncharacterized.
Purpose of the Study:
- To trace the projections from the dGIrvs2 in rats.
- To identify the cortical and subcortical targets of JCMS proprioceptive information originating from dGIrvs2.
Main Methods:
- Anterograde tracing using biotinylated dextranamine.
- Injection into the electrophysiologically identified dGIrvs2 in rats.
- Analysis of labeled axon terminal distribution.
Main Results:
- Labeled terminals showed ipsilateral predominance.
- Projections were observed in sensorimotor areas (somatosensory cortices, agranular cortices, orbital cortex).
- Significant projections were also found in basal ganglia, amygdala, extended amygdala, and various thalamic nuclei, including limbic regions.
Conclusions:
- JCMS proprioceptive information is relayed from dGIrvs2 to diverse brain regions.
- These pathways connect sensorimotor processing with emotional and limbic circuits.
- This suggests a role for jaw proprioception in integrating sensory information with affective states.
Related Concept Videos
02:18Fischer Projections
16.6K
Learning to draw Fischer projections of molecules and understanding their relevance plays a crucial role in the visual depiction of organic molecules. A Fischer projection is a two-dimensional projection on a planar surface to simplify the three-dimensional wedge–dash representation of molecules. This is especially helpful in the case of molecules with multiple chiral centers that can be difficult to draw. Here, all the bonds of interest are represented as horizontal or vertical lines. While...
16.6K
02:06Newman Projections
21.2K
Different notations are used to represent the three-dimensional structure of molecules on two-dimensional surfaces. One of the most commonly used representations is the dash-wedge formula. The dashed wedges, solid wedges, and the plane lines indicate the groups situated behind the plane, coming out of the plane, and in the plane, respectively.
The organic molecules rotate across the single bonds leading to numerous temporary three-dimensional structures of varying energy known as...
The organic molecules rotate across the single bonds leading to numerous temporary three-dimensional structures of varying energy known as...
21.2K
01:15Receiver Operating Characteristic Plot
489
A ROC (Receiver Operating Characteristic) plot is a graphical tool used to assess the performance of a binary classification model by illustrating the trade-off between sensitivity (true positive rate) and specificity (false positive rate). By plotting sensitivity against 1 - specificity across various threshold settings, the ROC curve shows how well the model distinguishes between classes, with a curve closer to the top-left corner indicating a more accurate model. The area under the ROC curve...
489
01:29Coordinates and Map Projections
620
Coordinates and map projections are essential tools in accurately representing the Earth's surface for various applications, ranging from navigation to spatial analysis. The latitude and longitude coordinate system is a universally recognized framework for defining locations. Latitude specifies the distance of a point north or south of the equator, measured in degrees from 0° at the equator to 90° at the poles. Longitude indicates a location's position east or west of the prime meridian,...
620
01:21Association Areas of the Cortex
9.4K
Association areas are regions of the cerebral cortex that do not have a specific sensory or motor function. Instead, they integrate and interpret information from various sources to enable higher cognitive processes such as memory, learning, and decision-making. Some key association areas include the following:
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
9.4K
01:14Motor and Sensory Areas of the Cortex
7.6K
The cerebral cortex, the brain's outermost layer, is pivotal in processing complex cognitive tasks, emotions, and various sensory inputs and executing voluntary motor activities. This intricate structure is divided into three primary functional areas: the motor areas, sensory areas, and association areas.
Motor Areas
The motor areas located in the frontal lobe are central to controlling voluntary movements. This region is further subdivided into the primary motor cortex and the premotor cortex....
Motor Areas
The motor areas located in the frontal lobe are central to controlling voluntary movements. This region is further subdivided into the primary motor cortex and the premotor cortex....
7.6K