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The present study examined the effect of perceived motion-in-depth on temporal interval perception. We required subjects to estimate the length of a short empty interval starting from the offset of a first marker and ending with the onset of a second marker. The size of the markers was manipulated so that the subjects perceived a visual object as approaching or receding. We demonstrated that the empty intervals between markers was perceived as taking shorter to view when the object was perceived as approaching than when it was perceived as receding. We found in addition that the motion-in-depth effect disappeared when the shape continuity between the first and second marker was broken or when the object approached but missed the face. We conclude that anticipated collision of an approaching object altered perception of an empty interval. (Contains 1 table and 3 figures.)

Highly boron-doped diamond (BDD) was deposited on chemically etched micrometer-sized tungsten wires using microwave plasma assisted chemical vapor deposition (MPCVD), and these were used to fabricate BDD microelectrodes. BDD microelectrodes with very small diameter (about 5 [micro]m) and 250 [micro]m in length could be made successfully. In addition to the unique properties of BDD electrodes, such as a very low background current, high stability, and selective oxidation of dopamine (DA) in the presence of ascorbic acid (AA), other superior properties of the microelectrodes, including a constant current response, an increase in the mass transport, and the ability, for use in high resistance media were also shown. An application study was conducted for in vivo detection of DA in mouse brain, where the BDD microelectrode was inserted into the corpus striatum of the mouse brain. A clear signal current response following medial forebrain bundle (MFB) stimulation could be obtained with high sensitivity. Excellent stability was achieved, indicating that the BDD microelectrodes are very promising for future in vivo electroanalysis.

The role of the climbing fiber input to the cerebellum has been enigmatic, with recent studies focusing on its temporal and spatial firing patterns. Debate remains as to whether climbing fibers provide a periodic clock for coordinating movements or lead to long-term modification of Purkinje cell activity as the basis of motor learning. Rhythmic and synchronous activity of climbing fibers can cause movements at the same frequency in some preparations, suggesting a role in motor timing. However, in awake monkeys climbing fiber signals have been reported to occur at random, presenting a problem for clock theories. Yet synchronous patterns of discharge are consistently observed among several Purkinje cells within a narrow parasagittal longitudinal band. Here, we review recent experimental and theoretical studies and attempt to provide a coherent account of the interplay between rhythmicity, randomness and synchrony in climbing fiber activity, with a particular reference to studies in chaos.

Cerebellar Purkinje cells pick up two kinds of synaptic inputs: one climbing fibre synapse from the brain stem's inferior olive nuclear synapse and sevral parallel fibre inputs from cerebellar granule cells. Arousal of the climbing fibre synapse causes a massive response, called the complex spike, occurring at low frequency. A new study analyses the link between motor activity and complex spike firing during arm movements. It is suggested that complex spikes arising early in a reaching movement encode target location, while those at the end of the cycle encode final error as the movement is completed.