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Open-field arena boundary is a primary object of exploration for Drosophila.

Soibam B, Mann M, Liu L, Tran J, Lobaina M, Kang YY, Gunaratne GH, Pletcher S, Roman G - Brain Behav (2012)

Bottom Line: These experiments support the conclusion that the wall-following behavior of Drosophila is best characterized by a preference for the arena boundary, and not thigmotaxis or centrophobicity.Since the boundary preference could derive from highly linear trajectories, we further developed a simulation program to model the effects of turn angle on the boundary preference.Hence, low turn angled movement does not drive the boundary preference.

View Article: PubMed Central - PubMed

ABSTRACT
Drosophila adults, when placed into a novel open-field arena, initially exhibit an elevated level of activity followed by a reduced stable level of spontaneous activity and spend a majority of time near the arena edge, executing motions along the walls. In order to determine the environmental features that are responsible for the initial high activity and wall-following behavior exhibited during exploration, we examined wild-type and visually impaired mutants in arenas with different vertical surfaces. These experiments support the conclusion that the wall-following behavior of Drosophila is best characterized by a preference for the arena boundary, and not thigmotaxis or centrophobicity. In circular arenas, Drosophila mostly move in trajectories with low turn angles. Since the boundary preference could derive from highly linear trajectories, we further developed a simulation program to model the effects of turn angle on the boundary preference. In an hourglass-shaped arena with convex-angled walls that forced a straight versus wall-following choice, the simulation with constrained turn angles predicted general movement across a central gap, whereas Drosophila tend to follow the wall. Hence, low turn angled movement does not drive the boundary preference. Lastly, visually impaired Drosophila demonstrate a defect in attenuation of the elevated initial activity. Interestingly, the visually impaired w(1118) activity decay defect can be rescued by increasing the contrast of the arena's edge, suggesting that the activity decay relies on visual detection of the boundary. The arena boundary is, therefore, a primary object of exploration for Drosophila.

No MeSH data available.


Related in: MedlinePlus

Drosophila visually attend the arena's edge during exploration. Wild-type Canton-S, w1118, and norpA7 were examined in circular arenas that had either a clear or opaque boundary. The activity of the normally sighted Canton-S and the blind norpA7 did not significantly change in the two different arenas. However, the visually impaired w1118 flies demonstrated distinct differences (Bonferroni–Dunn; P < 0.0001). The increased contrast obtained with the darkened arena wall rescued the w1118 activity decay phenotype. n = 24 for each genotype/condition.
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fig08: Drosophila visually attend the arena's edge during exploration. Wild-type Canton-S, w1118, and norpA7 were examined in circular arenas that had either a clear or opaque boundary. The activity of the normally sighted Canton-S and the blind norpA7 did not significantly change in the two different arenas. However, the visually impaired w1118 flies demonstrated distinct differences (Bonferroni–Dunn; P < 0.0001). The increased contrast obtained with the darkened arena wall rescued the w1118 activity decay phenotype. n = 24 for each genotype/condition.

Mentions: The propensity to walk in relatively straight lines may either cause the edge preference or develop as a result of this preference. To determine if the measured propensity for low turn angles is sufficient to account for the observed wall-following behavior, we have used Flymatron to systematically test the effect of field of motion (FoM) on the spatial orientation behavior of simulated flies (Fig. 6). The simulation was run for each arena with 20 pseudo-randomly chosen starting positions by altering the maximum FoM, an FoM of 30° allowed turning angle of 15° to the right and 15° to the left of the fly's direction of movement, and choosing step size randomly as zero to five nodes. In these simulations, we recorded the node visits and movement history within specific areas that matched our previous experimental measurements (Fig. 2). Canton-S will spend ∼90–95% of the time in the outer one-third of an 8.4-cm arena (Liu et al. 2007); this edge preference corresponded to a 24° FoM or 12° turn angle (Fig. 8A), approximately the same value for the peak turn angle of Canton-S within edge zone (Fig. 5A).


Open-field arena boundary is a primary object of exploration for Drosophila.

Soibam B, Mann M, Liu L, Tran J, Lobaina M, Kang YY, Gunaratne GH, Pletcher S, Roman G - Brain Behav (2012)

Drosophila visually attend the arena's edge during exploration. Wild-type Canton-S, w1118, and norpA7 were examined in circular arenas that had either a clear or opaque boundary. The activity of the normally sighted Canton-S and the blind norpA7 did not significantly change in the two different arenas. However, the visually impaired w1118 flies demonstrated distinct differences (Bonferroni–Dunn; P < 0.0001). The increased contrast obtained with the darkened arena wall rescued the w1118 activity decay phenotype. n = 24 for each genotype/condition.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3345355&req=5

fig08: Drosophila visually attend the arena's edge during exploration. Wild-type Canton-S, w1118, and norpA7 were examined in circular arenas that had either a clear or opaque boundary. The activity of the normally sighted Canton-S and the blind norpA7 did not significantly change in the two different arenas. However, the visually impaired w1118 flies demonstrated distinct differences (Bonferroni–Dunn; P < 0.0001). The increased contrast obtained with the darkened arena wall rescued the w1118 activity decay phenotype. n = 24 for each genotype/condition.
Mentions: The propensity to walk in relatively straight lines may either cause the edge preference or develop as a result of this preference. To determine if the measured propensity for low turn angles is sufficient to account for the observed wall-following behavior, we have used Flymatron to systematically test the effect of field of motion (FoM) on the spatial orientation behavior of simulated flies (Fig. 6). The simulation was run for each arena with 20 pseudo-randomly chosen starting positions by altering the maximum FoM, an FoM of 30° allowed turning angle of 15° to the right and 15° to the left of the fly's direction of movement, and choosing step size randomly as zero to five nodes. In these simulations, we recorded the node visits and movement history within specific areas that matched our previous experimental measurements (Fig. 2). Canton-S will spend ∼90–95% of the time in the outer one-third of an 8.4-cm arena (Liu et al. 2007); this edge preference corresponded to a 24° FoM or 12° turn angle (Fig. 8A), approximately the same value for the peak turn angle of Canton-S within edge zone (Fig. 5A).

Bottom Line: These experiments support the conclusion that the wall-following behavior of Drosophila is best characterized by a preference for the arena boundary, and not thigmotaxis or centrophobicity.Since the boundary preference could derive from highly linear trajectories, we further developed a simulation program to model the effects of turn angle on the boundary preference.Hence, low turn angled movement does not drive the boundary preference.

View Article: PubMed Central - PubMed

ABSTRACT
Drosophila adults, when placed into a novel open-field arena, initially exhibit an elevated level of activity followed by a reduced stable level of spontaneous activity and spend a majority of time near the arena edge, executing motions along the walls. In order to determine the environmental features that are responsible for the initial high activity and wall-following behavior exhibited during exploration, we examined wild-type and visually impaired mutants in arenas with different vertical surfaces. These experiments support the conclusion that the wall-following behavior of Drosophila is best characterized by a preference for the arena boundary, and not thigmotaxis or centrophobicity. In circular arenas, Drosophila mostly move in trajectories with low turn angles. Since the boundary preference could derive from highly linear trajectories, we further developed a simulation program to model the effects of turn angle on the boundary preference. In an hourglass-shaped arena with convex-angled walls that forced a straight versus wall-following choice, the simulation with constrained turn angles predicted general movement across a central gap, whereas Drosophila tend to follow the wall. Hence, low turn angled movement does not drive the boundary preference. Lastly, visually impaired Drosophila demonstrate a defect in attenuation of the elevated initial activity. Interestingly, the visually impaired w(1118) activity decay defect can be rescued by increasing the contrast of the arena's edge, suggesting that the activity decay relies on visual detection of the boundary. The arena boundary is, therefore, a primary object of exploration for Drosophila.

No MeSH data available.


Related in: MedlinePlus