Cerebral Cortex

Cerebral Cortex

Question 1. Write a short note on the anterior commissure.
Answer.

The anterior commissure is a small, round bundle of commissural fibres that crosses the midline in the upper part of the lamina terminalis. It consists of two components:

• A large, posterior neocortical component, which interconnects the cortical areas of the lower and anterior parts of the temporal poles.
• A smaller, anterior paleocortical component, which interconnects the olfactory regions, such as olfactory bulbs and olfactory tubercles, of the two sides.

Cerebral cortex

Question 2. Write a short note on thalamic radiation.
Answer.

With few exceptions, all the afferent fibres to the brain relay in the thalamus. From the thalamus, the thalamocortical fibres radiate in different directions to reach the widespread area of the cerebral cortex (thalamic radiation). The important thalamocortical fibres (or thalamic radiations) are as follows:

Functions of cerebral cortex

• Sensory radiation from the thalamus to the sensory cortex in the postcentral gyrus.
• Auditory radiation from the medial geniculate body to the auditory cortex in the temporal lobe.
• Optic radiation from the lateral geniculate body to the visual cortex in the occipital lobe.