During volitional muscle activation, motor units often fire with varying discharge patterns that include brief, high-frequency bursts of activity. These variations in the activation rate allow the central nervous system to precisely control the forces produced by the muscle. The present study explores how varying the instantaneous frequency of stimulation pulses within a train affects nonisomet...

This paper aims to develop a multi-objective model for scheduling cargo trains faced by the costs of tardiness and earliness, time limitations, queue priority and limited station lines. Based upon the Islamic Republic of Iran Railway Corporation (IRIRC) regulations, passenger trains enjoy priority over other trains for departure. Therefore, the timetable of cargo trains must be determined based...

Cochlear implant speech processors transmit temporal features of sound as amplitude modulation of constant-rate electrical pulse trains. This study evaluated the central representation of amplitude modulation in the form of phase-locked firing of neurons in the auditory cortex. Anesthetized pigmented guinea pigs were implanted with cochlear electrode arrays. Stimuli were 254 pulse/s (pps) train...

Cochlear-implant speech processors transmit temporal features of sound as amplitude modulation of constant-rate electrical pulse trains. The present study evaluated the central representation of amplitude modulation in the form of phase-locked firing of neurons in the auditory cortex. Anesthetized pigmented guinea pigs were implanted with cochlear electrode arrays. Stimuli were 254 pulse/s (pps...

objective(s):to determine the effect of acetylcholine (ach), pilocarpine, and atropine on pain evoked responses of pain excited neurons (pen) and pain inhibited neurons (pin) in hippocampal ca3 region of morphine addicted rats. materials and methods:female wistar rats, weighing between 230-260 g were used in this study. morphine addicted rats were generated by subcutaneous injection of increasi...

Vasopressin and oxytocin were administered intracerebro-ventriculary to rabbits in order to test their effects on the brain electrical activity. The effects were manifested by an increase or decrease in the amount of energy of electrical pulse trains required to produce habituation which is known to occur after repetitive stimulation of the midbrain reticular - formation. Vasopressin inhibited ...

Control of posture and movement requires control of the output from motoneurons. Motoneurons of human lower limb muscles exhibit sustained, submaximal activity to high-frequency electrical trains, which has been hypothesized to be partly triggered by monosynaptic Ia afferents. The possibility to trigger such behavior in upper limb motoneurons and the potential unique role of Ia afferents to tri...

For successful visual perception by visual prosthesis using electrical stimulation, it is essential to develop an effective stimulation strategy based on understanding of retinal ganglion cell (RGC) responses to electrical stimulation. We studied RGC responses to repetitive electrical stimulation pulses to develop a stimulation strategy using stimulation pulse frequency modulation. Retinal patc...

We monitored presynaptic exocytosis and vesicle recycling at neuromuscular junctions of transgenic mice expressing synaptopHluorin (spH), using simultaneous optical and electrophysiological recordings. Synaptic transmission was indistinguishable from that in wild-type controls. Fluorescence rose during and decayed monotonically after stimulus trains to the nerve, with amplitudes and decay times...

This study examined the catchlike property of skeletal muscle during eccentric and concentric isovelocity contractions of fresh and fatigued quadriceps femoris muscles of 10 healthy subjects. During concentric contractions of fresh muscles, stimulation trains that elicited a catchlike response (CITs) produced greater force outputs and rates of rise force than comparable constant-frequency train...