Caffeine Consumption Is Associated With Higher Level of Physical Activity in Japanese Women.

Caffeine has been described as a sports performance-enhancing substance. However, it is unclear whether it can increase the level of physical activity (PA) in nonathletic individuals. This study investigates the relationship between daily caffeine consumption and (a) daily PA/fitness or (b) intervention-induced changes in PA in women and men.

Cortical mechanisms of unilateral voluntary motor inhibition in humans.

While motor control is very often a goal-oriented event, little is known about the mechanisms underlying the termination of motor performance. To investigate what type of cortical activation underlies the muscle relaxation required to terminate the act, we performed single- and double-pulse transcranial magnetic stimulation (TMS) studies during voluntary muscle relaxation in nine normal volunteers. Subjects maintained a weak isometric contraction of the right first dorsal interosseous muscle (FDI), and either increased the level of contraction (Contraction), terminated the contraction (Relaxation), or maintained it (No-go) depending on a visual cue.

Low-frequency rTMS over lateral premotor cortex induces lasting changes in regional activation and functional coupling of cortical motor areas.

Objective: To study the effect of 0.9 Hz repetitive transcranial magnetic stimulation (rTMS) of the lateral premotor cortex on neuronal activity in cortical motor areas during simple motor tasks.

Methods: In 8 subjects, electroencephalogram (EEG) and electromyogram (EMG) were simultaneously recorded during voluntary contractions of the thumb before and after a 15 min train of 0.

Transcranial magnetic stimulation (TMS) of the sensorimotor cortex and medial frontal cortex modifies human pain perception.

Objective: Although recent neuroimaging studies have shown that painful stimuli can produce activity in multiple cortical areas, the question remains as to the role of each area in particular aspects of human pain perception. To solve this problem we used transcranial magnetic stimulation (TMS) as an 'interference approach' tool to test the consequence on pain perception of disrupting activity in several areas of cortex known to be activated by painful input.

Methods: Weak CO(2) laser stimuli at an intensity around the threshold for pain were given to the dorsum of the left hand in 9 normal subjects.

Two conserved structural components, A-rich bulge and P4 XJ6/7 base-triples, in activating the group I ribozymes.

Background: The A-rich bulge of the group I intron ribozyme, a highly conserved structural element in its P5 peripheral region, plays a significant role in activating the ribozyme. The bulge has been known to interact with the P4 stem forming P4 XJ6/7 base-triples in the conserved core. The base-triples by themselves have also been identified as a distinctive element responsible for enhancing the activity of the ribozyme.

Nausea as a complication of low-frequency repetitive transcranial magnetic stimulation of the posterior fossa.

Background: Transcranial magnetic stimulation (TMS) can non-invasively investigate the function of human brain. However, it can induce a focal pain at the stimulated site on the scalp or seizures when applied with high frequency (>1 Hz). Here we report an induction of nausea as a complication of low-frequency repetitive TMS (rTMS) of the cerebellum.