Ablation of the ‘somatosensory area I’ of the cerebral coex leads to :
**Core Concept**
The somatosensory area I (also known as the primary somatosensory cortex or S1) is a critical region in the brain responsible for processing basic sensory information, such as touch, temperature, and vibration. It is located in the postcentral gyrus of the parietal lobe and receives input from the thalamus.
**Why the Correct Answer is Right**
Damage or ablation of the somatosensory area I leads to a loss of fine motor skills, proprioception, and tactile sensation. This is because the S1 region is involved in the processing of basic sensory information, which is essential for motor control and spatial awareness. The loss of sensory input from the S1 region can result in difficulties with tasks that require fine motor control, such as writing or buttoning a shirt.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is likely incorrect because ablation of the S1 region would not directly affect the motor aspects of language, such as speaking or writing. Language processing is primarily localized to the Broca's area and Wernicke's area in the left hemisphere of the brain.
**Option B:** This option is incorrect because the somatosensory area I is not directly involved in the processing of visual information. The primary visual cortex (V1) is located in the occipital lobe and is responsible for processing basic visual information.
**Option C:** This option is incorrect because the somatosensory area I is not directly involved in the regulation of autonomic functions, such as heart rate or blood pressure. These functions are primarily regulated by the autonomic nervous system, which includes the sympathetic and parasympathetic nervous systems.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that the somatosensory area I is involved in the processing of basic sensory information, which is essential for motor control and spatial awareness. Damage to this region can result in difficulties with fine motor skills and tactile sensation.
**Correct Answer: C. Loss of proprioception and fine motor skills.**