Tag: community health and hygiene

Cardiac activity could be moderated by the autonomous neural system. The action of sympathetic nerve fibres increases the heart rate and the stroke volume, while that of the parasympathetic nerve fibres decrease these.

Thus, the correct answer is 'The sympathetic system stimulates heart rate and stroke volume.'

An electroencephalogram (EEG) is a test that detects electrical activity in the brain using small, flat metal discs (electrodes) attached to scalp. 

Evoked potential studies measure electrical activity in the brain in response to stimulation of sight, sound, or touch. Stimuli delivered to the brain through each of these senses evoke minute electrical signals. These signals travel along the nerves and through the spinal cord to specific regions of the brain and are picked up by electrodes, amplified, and displayed for a doctor to interpret. Evoked potentials studies involve three major tests that measure response to visual, auditory, and electrical stimuli. Evoked potential studies may be used to assess hearing or sight, especially in infants and children, to diagnose disorders of the optic nerve, and to detect tumors or other problems affecting the brain and spinal cord. The tests may also be performed to assess brain function during a coma.

A SQUID (superconducting quantum interference device) is a very sensitive magnetometer used to measure extremely subtle magnetic fields, based on superconducting loops containing Josephson junctions. SQUIDs are sensitive enough to measure fields as low as 5 aT (51018 T) within a few days of averaged measurements. Magnetoencephalography (MEG), uses measurements from an array of SQUIDs to make inferences about neural activity inside brains. Because SQUIDs can operate at acquisition rates much higher than the highest temporal frequency of interest in the signals emitted by the brain (kHz), MEG achieves good temporal resolution.

Reserpine is an indole alkaloid, antipsychotic and antihypertensive drug that has been used for the control of high blood pressure.
Rustom Jal Vakil was the first to pioneer the use of resperine to control hypertension.
Thus, the correct answer is option (A), 'Jal Vakil'.

$\beta$-wave or $\eta$ rhythm is the term used to designate the frequency range of human brain activity between 12.5 and 30 Hz.
Thus, the correct answer is option C.

A permanent record of the electric events occurring during a cardiac cycle made on a graph paper in a wave form called electrocardiogram. The electric events include depolarization and repolarization of the auricles and ventricles bringing about their contraction and relaxation. The instrument used to record hearts electric event is named electrocardiograph.