Limits...
Reduced performance of prey targeting in pit vipers with contralaterally occluded infrared and visual senses.

Chen Q, Deng H, Brauth SE, Ding L, Tang Y - PLoS ONE (2012)

Bottom Line: Both visual and infrared (IR) senses are utilized in prey targeting by pit vipers.Visual and IR inputs project to the contralateral optic tectum where they activate both multimodal and bimodal neurons.Performance was significantly poorer when only a single eye or pit was available.

View Article: PubMed Central - PubMed

Affiliation: Department of Herpetology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China.

ABSTRACT
Both visual and infrared (IR) senses are utilized in prey targeting by pit vipers. Visual and IR inputs project to the contralateral optic tectum where they activate both multimodal and bimodal neurons. A series of ocular and pit organ occlusion experiments using the short-tailed pit viper (Gloydius brevicaudus) were conducted to investigate the role of visual and IR information during prey targeting. Compared with unoccluded controls, snakes with either both eyes or pit organs occluded performed more poorly in hunting prey although such subjects still captured prey on 75% of trials. Subjects with one eye and one pit occluded on the same side of the face performed as well as those with bilateral occlusion although these subjects showed a significant targeting angle bias toward the unoccluded side. Performance was significantly poorer when only a single eye or pit was available. Interestingly, when one eye and one pit organ were occluded on opposite sides of the face, performance was poorest, the snakes striking prey on no more than half the trials. These results indicate that, visual and infrared information are both effective in prey targeting in this species, although interference between the two modalities occurs if visual and IR information is restricted to opposite sides of the brain.

Show MeSH

Related in: MedlinePlus

Demonstration of experiment and recording.A schematic diagram illustrating the experimental set-up used to measure behavior during targeting trials. A camcorder mounted on a tripod and connected to a PC was used to record the behavior of the snakes. A grid superimposed on the image was used to quantify strike distances and angles. At the beginning of each trial a mouse of appropriate size was placed directly in front of the head of the snake at the edge of the arena (see Materials and Methods for explanation).
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3351397&req=5

pone-0034989-g005: Demonstration of experiment and recording.A schematic diagram illustrating the experimental set-up used to measure behavior during targeting trials. A camcorder mounted on a tripod and connected to a PC was used to record the behavior of the snakes. A grid superimposed on the image was used to quantify strike distances and angles. At the beginning of each trial a mouse of appropriate size was placed directly in front of the head of the snake at the edge of the arena (see Materials and Methods for explanation).

Mentions: All experimental trials took place in the snakes’ home cages in order to minimize possible effects of changing the environment on the pit vipers’ response to the prey. For the experimental trials, feedings were staged in a soundproof room, videotaped, and monitored by experimenters behind a screen (see Figure 5). During the experiment, the temperature was held constant at 25°C and two energy efficient bulbs (5 W, Philips) were used to light the room. All targeting trials were monitored visually by the experimenters in order to ensure that neither the mice nor snakes suffered unnecessary pain.


Reduced performance of prey targeting in pit vipers with contralaterally occluded infrared and visual senses.

Chen Q, Deng H, Brauth SE, Ding L, Tang Y - PLoS ONE (2012)

Demonstration of experiment and recording.A schematic diagram illustrating the experimental set-up used to measure behavior during targeting trials. A camcorder mounted on a tripod and connected to a PC was used to record the behavior of the snakes. A grid superimposed on the image was used to quantify strike distances and angles. At the beginning of each trial a mouse of appropriate size was placed directly in front of the head of the snake at the edge of the arena (see Materials and Methods for explanation).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3351397&req=5

pone-0034989-g005: Demonstration of experiment and recording.A schematic diagram illustrating the experimental set-up used to measure behavior during targeting trials. A camcorder mounted on a tripod and connected to a PC was used to record the behavior of the snakes. A grid superimposed on the image was used to quantify strike distances and angles. At the beginning of each trial a mouse of appropriate size was placed directly in front of the head of the snake at the edge of the arena (see Materials and Methods for explanation).
Mentions: All experimental trials took place in the snakes’ home cages in order to minimize possible effects of changing the environment on the pit vipers’ response to the prey. For the experimental trials, feedings were staged in a soundproof room, videotaped, and monitored by experimenters behind a screen (see Figure 5). During the experiment, the temperature was held constant at 25°C and two energy efficient bulbs (5 W, Philips) were used to light the room. All targeting trials were monitored visually by the experimenters in order to ensure that neither the mice nor snakes suffered unnecessary pain.

Bottom Line: Both visual and infrared (IR) senses are utilized in prey targeting by pit vipers.Visual and IR inputs project to the contralateral optic tectum where they activate both multimodal and bimodal neurons.Performance was significantly poorer when only a single eye or pit was available.

View Article: PubMed Central - PubMed

Affiliation: Department of Herpetology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China.

ABSTRACT
Both visual and infrared (IR) senses are utilized in prey targeting by pit vipers. Visual and IR inputs project to the contralateral optic tectum where they activate both multimodal and bimodal neurons. A series of ocular and pit organ occlusion experiments using the short-tailed pit viper (Gloydius brevicaudus) were conducted to investigate the role of visual and IR information during prey targeting. Compared with unoccluded controls, snakes with either both eyes or pit organs occluded performed more poorly in hunting prey although such subjects still captured prey on 75% of trials. Subjects with one eye and one pit occluded on the same side of the face performed as well as those with bilateral occlusion although these subjects showed a significant targeting angle bias toward the unoccluded side. Performance was significantly poorer when only a single eye or pit was available. Interestingly, when one eye and one pit organ were occluded on opposite sides of the face, performance was poorest, the snakes striking prey on no more than half the trials. These results indicate that, visual and infrared information are both effective in prey targeting in this species, although interference between the two modalities occurs if visual and IR information is restricted to opposite sides of the brain.

Show MeSH
Related in: MedlinePlus