scholarly journals The human saccadic adaptation field across time

2018 ◽  
Vol 18 (10) ◽  
pp. 1012
Author(s):  
Eef Joosten ◽  
Therese Collins
2010 ◽  
Vol 3 (3) ◽  
Author(s):  
Fabian Schnier ◽  
Eckart Zimmermann ◽  
Markus Lappe

Adaptive shortening of a saccade influences the metrics of other saccades within a spatial window around the adapted target. Within this adaptation field visual stimuli presented before an adapted saccade are mislocalized in proportion to the change of the saccade metric. We investigated the saccadic adaptation field and associated localization changes for saccade lengthening, or outward adaptation. We measured the adaptation field for two different saccade adaptations (14 deg to 20 deg and 20 deg to 26 deg) by testing transfer to 34 different target positions. We measured localization judgements by asking subjects to localize a probe flashed before saccade onset. The amount of adaptation transfer differed for different target locations. It increased with increases of the horizontal component of the saccade and remained largely constant with deviation of the vertical component of the saccade. Mislocalization of probes inside the adaptation field was correlated with the amount of adaptation of saccades to the probe location. These findings are consistent with the assumption that oculomotor space and perceptual space are linked to each other.


2008 ◽  
Vol 99 (5) ◽  
pp. 2708-2718 ◽  
Author(s):  
Thérèse Collins ◽  
Dorine Vergilino-Perez ◽  
Laura Delisle ◽  
Karine Doré-Mazars

In the antisaccade task, subjects must execute an eye movement away from a visual target. Correctly executing an antisaccade requires inhibiting a prosaccade toward the visual target and programming a movement to the opposite side. This movement could be based on the inversion of the visual vector, corresponding to the distance between the fixation point and the visual target, or the motor vector of the unwanted prosaccade. We dissociated the two vectors by means of saccadic adaptation. Adaptation can be observed when systematic targeting errors are caused by the displacement of the visual target during the saccade. Adaptation progressively modifies saccade amplitude (defined by the motor vector) such that it becomes appropriate to the postsaccadic stimulus position and thus different from the visual vector of the target. If antisaccade preparation depended on visual vector inversion, rightward prosaccade adaptation should not transfer to leftward antisaccades (which are based on the same visual vector) but should transfer to rightward antisaccades (which are based on a visual vector inside the adaptation field). If antisaccade preparation depended on motor vector inversion, rightward prosaccade adaptation should transfer to leftward antisaccades (which are based on the same, adapted motor vector) but should not transfer to rightward antisaccades (which are based on a nonadapted motor vector). The results are in line with the first hypothesis, showing that vector inversion precedes saccadic adaptation and suggesting that antisaccade preparation depends on the inversion of the visual target vector.


Author(s):  
Elīna Gailīte

The article “Problems of defining folk dance in Latvia today” examines the aspects that affect the current situation in Latvia, where folk dances are understood as both folk dances that have not been modified by choreographers, dances passed down through generations that can be danced every day, and stage folk dances, which are a type of art performed by folk dance ensembles, created by choreographers and dances adapted to the stage performance. The research aim is to identify and describe the problems that currently exist in the Latvian cultural space, where the definition of folk dances creates tension in the public space and ambiguous opinions among dancers. Nowadays, it is possible to identify such concepts as, for example, folk dance, ethnographic dance, authentic dance, traditional dance, folklore dance, folk dance, folk dance adaptation, field dance, folk ballet, etc. Consistent use of concepts is rarely seen in the documents and research of cultural policymakers and the historical and contemporary works of choreographers and researchers. Often they are only described in general terms. A survey conducted in 2019 shows that dancers consider stage folk dances to be folk dances, and often this separation of dances is not important for them. Another problem is the designation of folk dance ensembles where stage folk dance dancers are dancing. The term misleads; it suggests that folk dances are danced there. However, this designation is linked to its historical time of origin. It is not insignificant that the stage folk dance is more popular, more visible, and massively represented at the Song and Dance Festival. Thus, a part of the society associates it with our folk dances.


2015 ◽  
Vol 56 (2) ◽  
pp. 947-955
Author(s):  
R. A. Raashid ◽  
A. M. F. Wong ◽  
A. Blakeman ◽  
H. C. Goltz

2011 ◽  
Vol 11 (11) ◽  
pp. 496-496
Author(s):  
T. Collins ◽  
J. Wallman

2000 ◽  
Vol 84 (4) ◽  
pp. 1809-1813 ◽  
Author(s):  
J. Ditterich ◽  
T. Eggert ◽  
A. Straube

A shift of the visual attention focus is known to precede saccades. However, how the metrics of both this presaccadic attention shift and the saccade are coupled is still unclear. We altered the saccade size by short-term saccadic adaptation to determine whether the attention focus would still be shifted to the location of the saccade target or to the modified postsaccadic eye position. The results showed that saccadic adaptation had no influence on the presaccadic attention shift. Thus either different processes determine the metrics of the attention shift and of the saccade or saccadic adaptation causes only modifications on a lower hierarchical level of saccade programming, thereby not influencing the metrics of the attention shift.


2011 ◽  
Vol 106 (3) ◽  
pp. 1399-1410 ◽  
Author(s):  
Fabian Schnier ◽  
Markus Lappe

Saccadic adaptation is a mechanism to increase or decrease the amplitude gain of subsequent saccades, if a saccade is not on target. Recent research has shown that the mechanism of gain increasing, or outward adaptation, and the mechanism of gain decreasing, or inward adaptation, rely on partly different processes. We investigate how outward and inward adaptation of reactive saccades transfer to other types of saccades, namely scanning, overlap, memory-guided, and gap saccades. Previous research has shown that inward adaptation of reactive saccades transfers only partially to these other saccade types, suggesting differences in the control mechanisms between these saccade categories. We show that outward adaptation transfers stronger to scanning and overlap saccades than inward adaptation, and that the strength of transfer depends on the duration for which the saccade target is visible before saccade onset. Furthermore, we show that this transfer is mainly driven by an increase in saccade duration, which is apparent for all saccade categories. Inward adaptation, in contrast, is accompanied by a decrease in duration and in peak velocity, but only the peak velocity decrease transfers from reactive saccades to other saccade categories, i.e., saccadic duration remains constant or even increases for test saccades of the other categories. Our results, therefore, show that duration and peak velocity are independent parameters of saccadic adaptation and that they are differently involved in the transfer of adaptation between saccade categories. Furthermore, our results add evidence that inward and outward adaptation are different processes.


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