scholarly journals Characterizing the gain change underlying presaccadic attention

2018 ◽  
Vol 18 (10) ◽  
pp. 1206
Author(s):  
Jasmine Pan ◽  
Hsin-Hung Li ◽  
Marisa Carrasco
Keyword(s):  
Gain Change

scholarly journals Short Communication: Humans and the missing C-sink: erosion and burial of soil carbon through time

2013 ◽  
Vol 1 (1) ◽  
pp. 45-52 ◽  
Author(s):  
T. Hoffmann ◽  
S. M. Mudd ◽  
K. van Oost ◽  
G. Verstraeten ◽  
G. Erkens ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Soil Carbon ◽  
Short Communication ◽  
Future Research ◽  
Residence Times ◽  
Fluvial System ◽  
Anthropogenic Soil ◽  
Atmospheric Carbon ◽  
Gain Change

Abstract. Is anthropogenic soil erosion a sink or source of atmospheric carbon? The answer depends on factors beyond hillslope erosion alone because the probable fate of mobilized soil carbon evolves as it traverses the fluvial system. The transit path, residence times, and the resulting mechanisms of C-loss or gain change significantly down-basin and are currently difficult to predict as soils erode and floodplains evolve – this should be a key focus of future research.

Multiple Motor Learning Experiences Enhance Motor Adaptability

2004 ◽  
Vol 16 (1) ◽  
pp. 65-73 ◽  
Author(s):  
Rachael D. Seidler
Keyword(s):  
Motor Learning ◽  
Learning Experiences ◽  
External Perturbation ◽  
Skill Learning ◽  
Learning Ability ◽  
Learning Capacity ◽  
Control Subjects ◽  
Movement Sequence ◽  
Experimental Subjects ◽  
Gain Change

Traditional motor learning theory emphasizes that skill learning is specific to the context and task performed. Recent data suggest, however, that subjects exposed to a variety of motor learning paradigms may be able to acquire general, transferable knowledge about skill learning processes. I tested this idea by having subjects learn five different motor tasks, three that were similar to each other and two that were not related. A group of experimental subjects first performed a joystick-aiming task requiring adaptation to three different visuomotor rotations, with a return to the null conditions between each exposure. They then performed the same joystick-aiming task but had to adapt to a change in display gain instead of rotation. Lastly, the subjects used the joystickaiming task to learn a repeating sequence of movements. Two groups of control subjects performed the same number of trials, but learned only the gain change or the movement sequence. Experimental subjects showed generalization of learning across the three visuomotor rotations. Experimental subjects also exhibited transfer of learning ability to the gain change and the movement sequence, resulting in faster learning than that seen in the control subjects. However, transient perturbations affected the movements of the experimental subjects to a greater extent than those of the control subjects. These data demonstrate that humans can acquire a general enhancement in motor skill learning capacity through experience, but it comes with a cost. Although movement becomes more adaptable following multiple learning experiences, it also becomes less stable to external perturbation.

scholarly journals Dependence of the Roll Angular Vestibuloocular Reflex (aVOR) on Gravity

2009 ◽  
Vol 102 (5) ◽  
pp. 2616-2626 ◽  
Author(s):  
Sergei B. Yakushin ◽  
Yongqing Xiang ◽  
Bernard Cohen ◽  
Theodore Raphan
Keyword(s):  
High Frequency ◽  
Head Tilt ◽  
Upright Position ◽  
Head Orientation ◽  
Vestibuloocular Reflex ◽  
Behavioral Differences ◽  
Adaptive Circuits ◽  
Phase Rotation ◽  
Central Organization ◽  
Gain Change

Little is known about the dependence of the roll angular vestibuloocular reflex (aVOR) on gravity or its gravity-dependent adaptive properties. To study gravity-dependent characteristics of the roll aVOR, monkeys were oscillated about a naso-occipital axis in darkness while upright or tilted. Roll aVOR gains were largest in the upright position and decreased by 7–15% as animals were tilted from the upright. Thus the unadapted roll aVOR gain has substantial gravitational dependence. Roll gains were also decreased or increased by 0.25 Hz, in- or out-of-phase rotation of the head and the visual surround while animals were prone, supine, upright, or in side-down positions. Gain changes, determined as a function of head tilt, were fit with a sinusoid; the amplitudes represented the amount of the gravity-dependent gain change, and the bias, the gravity-independent gain change. Gravity-dependent gain changes were absent or substantially smaller in roll (≈5%) than in yaw (25%) or pitch (17%), whereas gravity-independent gain changes were similar for roll, pitch, and yaw (≈20%). Thus the high-frequency roll aVOR gain has an inherent dependence on head orientation re gravity in the unadapted state, which is different from the yaw/pitch aVORs. This inherent gravitational dependence may explain why the adaptive circuits are not active when the head is tilted re gravity during roll aVOR adaptation. These behavioral differences support the idea that there is a fundamental difference in the central organization of canal-otolith convergence of the roll and yaw/pitch aVORs.

Gain change and threshold reduction of diode laser by injection locking

1998 ◽  
Vol 151 (4-6) ◽  
pp. 253-256 ◽  
Author(s):  
S Sivaprakasam ◽  
Ranjit Singh
Keyword(s):  
Diode Laser ◽  
Injection Locking ◽  
Gain Change
Sign in / Sign up

Export Citation Format

Share Document