Thalamus Modulates Consciousness via Layer-Specific Control of Cortex
Michelle J Redinbaugh1, Jessica M Phillips1, Niranjan A Kambi1
1Department of Psychology, University of Wisconsin-Madison, Madison, WI 53706, USA.
Neuron
|February 14, 2020
Summary
Neurons in the thalamus and deep cortical layers are crucial for consciousness. Stimulating the central lateral thalamus (CL) in anesthetized macaques restored wake-like brain activity, suggesting targeted stimulation for consciousness disorders.
Area of Science:
- Neuroscience
- Cognitive Neuroscience
Background:
- Consciousness is thought to involve large-scale thalamocortical and corticocortical interactions.
- The specific roles of different cortical layers and circuits in consciousness remain unclear.
Purpose of the Study:
- To investigate the contribution of specific neuronal populations and circuits to consciousness.
- To explore the causal role of thalamocortical interactions in maintaining consciousness.
Main Methods:
- Simultaneous electrophysiological recordings from the central lateral thalamus (CL) and frontoparietal cortex across cortical layers in macaques.
- Recordings were performed during natural sleep, anesthesia, and wakefulness.
- Causal investigation using targeted electrical stimulation of the CL in anesthetized macaques.
Main Results:
- Neurons in the thalamus and deep cortical layers exhibited the highest sensitivity to changes in consciousness levels across different anesthetic agents and sleep states.
- Deep-layer cortical activity was dependent on interactions with the CL.
- Deep-layer neurons provided feedback to superficial cortical layers, but not to deep layers, highlighting the importance of long-range feedback and intracolumnar signaling.
- Stimulation of the CL in anesthetized macaques restored arousal and wake-like neural processing in a location- and frequency-specific manner.
Conclusions:
- Consciousness is associated with layer-specific thalamocortical interactions.
- Deep cortical layers play a critical role in sustaining consciousness through interactions with the thalamus.
- Targeted deep brain stimulation, specifically of the CL, shows potential for treating disorders of consciousness.
Related Concept Videos
01:24Somatosensory, Motor, and Association Cortex
2.0K
The somatosensory cortex in the parietal lobes is crucial for interpreting sensory data such as touch, temperature, and proprioception. The somatosensory cortex, situated in the parietal lobes, plays a vital role in interpreting sensory information like touch, temperature, and proprioception—awareness of body position. This specialized brain region features an organized structure wherein neurons at the top primarily process sensations originating from the lower body. In contrast, those at...
2.0K
01:27Diencephalon: Thalamus and Information Relay
3.5K
The thalamus, often called “the gateway to the cerebral cortex,” is vital in processing and directing sensory and motor signals throughout the brain. Almost all inputs destined for the cerebral cortex, except for olfactory signals, are relayed through the thalamus. The thalamus is a sophisticated relay station, channeling information from various brain regions to the cerebral cortex, as well as a filter, prioritizing certain signals over others based on current physiological...
3.5K
01:30Diencephalon: Anatomical Regions
4.4K
The diencephalon, etymologically translated as 'through brain,' plays an integral role as the conduit between the cerebrum and the vast extent of the nervous system. However, the olfactory system is an exception, as it interfaces directly with the cerebrum. The diencephalon, deeply ensconced beneath the cerebrum, primarily consists of three paired structures — the thalamus, hypothalamus, and epithelamus. It also includes accessory structures such as the subthalamus, which houses the...
4.4K
01:22Lobes of the Cerebrum
3.6K
The cerebral cortex, a critical structure of the brain, is intricately divided into two hemispheres, each consisting of four distinct lobes: occipital, temporal, frontal, and parietal. These lobes function cooperatively to regulate various cognitive and sensory functions, forming the basis of our complex neural capabilities.
Frontal lobe
The frontal lobes, located behind the forehead, are the command center of our brain, controlling personality, intelligence, and voluntary muscle movements....
Frontal lobe
The frontal lobes, located behind the forehead, are the command center of our brain, controlling personality, intelligence, and voluntary muscle movements....
3.6K
01:30Organization of the Brain
2.1K
The brain is an integral component of the nervous system and serves as the center for processing sensory inputs, making decisions, and directing bodily actions. This complex organ is organized into three primary sections: the hindbrain, midbrain, and forebrain, each responsible for a range of vital functions.
Hindbrain
The hindbrain, located at the base of the brain, plays a vital role in regulating automatic processes that sustain life. It includes the medulla oblongata, which is essential for...
Hindbrain
The hindbrain, located at the base of the brain, plays a vital role in regulating automatic processes that sustain life. It includes the medulla oblongata, which is essential for...
2.1K
01:14Motor and Sensory Areas of the Cortex
6.6K
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....
6.6K