Thalamus Function

The brain is said to be the most complex organ in the human body. It is with this organ, that the human being is able to think, have emotions, move and for that matter also dream. Looking at the complexity of the brain, it is not surprising, that there are different parts located in the brain. The anatomy of central nervous system can be described as follows. The brain along with the spinal cord make up central nervous system, while the nerves located in all parts of the body make up for peripheral nervous system. One part of the brain is the thalamus. The word thalamus is derived from the Greek language meaning room or chamber. It is a part of the limbic system. The thalamus is a mid-line paired symmetrical structure in the brain. It is located between the cerebral cortex and mid-brain, not only physically, but also in terms of neurological connections. We will read further about the thalamus function and location now.

Thalamus Location

The largest structure in the diencephalon, which is the part of the brain, which is located between the mid-brain and fore-brain. The diencephalon also includes the dorsally located epithalamus and perithalamus. Since the ontogenetic origins of epithalamus and the perithalamus are different, they are formally distinguished from the thalamus proper. Anatomically speaking, the thalamus is located on top of the brain stem, closer to the center of the brain, hence is a position to send nerve fibers out from the cerebral cortex, to all parts of the body. In humans, the thalamus can be divided into two halves, which are prominent bulb-shaped masses and are located obliquely and symmetrically on each side of the third ventricle.

What is the Thalamus Function

The diagram of the brain and its functions is complex, hence we will, in this article, only read about thalamus function. The basic thalamus function in the brain is to process and relay movement and sensory information. It can be called the relay station of the body, which takes in sensory information from different parts of the body and passes it on to the cerebral cortex. The passing of information also happens in the reverse direction. Information is also passed from the cerebral cortex to the thalamus, which is then in turn sent out to the other parts of the body. To take an example, inputs from the retina are sent to the lateral geniculate nucleus region of the thalamus, which in turn projects the primary visual cortex in the occipital lobe. Each of the sensory relay areas receive strong projections from the cerebral cortex.

The other thalamus function is to regulate the sleeping and wakefulness states. The thalamus has strong reciprocal connections with the cerebral cortex, which in turn form the thalamo-cortico-thamlamic circuits, which take care of consciousness. The thalamus also has a major role to play in regulating arousal, level of awareness and activity.

Other than these thalamus function, there are other functions of the thalamus as well. These functions are linked to the different regions of the thalamus. This is true for many of the sensory systems, namely auditory, somatic, visceral, gustatory and visual systems, in which the localized lesions provoke specific sensory deficits. A major role of the thalamus is related to the motor systems of the body. Filtering the signals is an important thalamus function and any changes in this filtering may show physiological effects.

Any damage to the thalamus can result in comatose situation, which can be reversible or irreversible or can affect the motor activities of the person. The very fact, that the person may lose his/her consciousness, stress the importance of thalamus function in the body. To sum up the thalamus function in short, the thalamus relays sensations, special sense and motor signals to the cerebral cortex and regulate the states of consciousness, sleep and alertness.