What are the EEG waves recorded for parieto occipital region with subject awake an eyes closed:
**Core Concept**
The EEG waves recorded from the parieto-occipital region of the brain, particularly with the subject awake and eyes closed, reflect the state of cortical activity in the visual processing areas. This region is responsible for processing visual information and is characterized by a specific pattern of electrical activity.
**Why the Correct Answer is Right**
When a subject is awake and eyes closed, the EEG waves recorded from the parieto-occipital region typically show a dominant frequency of 8-12 Hz, which is characteristic of alpha waves. Alpha waves are a type of brain wave that is associated with relaxation, closed eyes, and decreased cortical activity. They are generated by the synchronized activity of pyramidal neurons in the visual cortex, which is a hallmark of the parieto-occipital region.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not provided, but typically, beta waves (13-30 Hz) are associated with active thinking, problem-solving, and motor activity, which is not consistent with the subject being awake and eyes closed.
**Option B:** Delta waves (0.5-4 Hz) are typically seen in deep sleep or coma and are not characteristic of the awake and relaxed state.
**Option C:** Theta waves (4-8 Hz) are often seen in drowsiness or early stages of sleep and are not the dominant frequency in the parieto-occipital region with eyes closed.
**Clinical Pearl / High-Yield Fact**
Alpha waves are a key feature of the relaxed, awake state and can be used as a marker for normal brain function in clinical settings. However, it's worth noting that alpha waves can also be seen in other states, such as during meditation or relaxation, and can be influenced by various factors, including sleep deprivation and certain medications.
**Correct Answer: A. Alpha waves.**