Neurons of the Toad’s Visual System

Methodology

100

How were the toads immobilized for the experiment?

They were injected with succinylcholine into the lymphatic sac.

200

Which neuron class was found to be the most inhibited by extension perpendicular to the direction of movement?

Neuron class TH3 (thalamic-pretectal neurons)

300

What was the background illumination used in the experiment meant to simulate?

The luminance was used to simulate moonlight. 

Figures

100

Based on figure 3, which type of tectal neuron (tectum 1 or tectum 2) is more sensitive to changes in stripe length?

Tectum 2 neurons are more sensitive to changes in stripe length. 

200

Based on figure 4 – Why do you think there are more neural impulse firings of the horizontal rectangle as it traverses past the receptive field of the tectum-2- neuron?  

As the horizontal rectangle enters and covers the receptive field of the neuron, more spikes are generated as they resemble natural prey-like stimuli.  

300

Based on figure 5: tectum one neurons responded the most to which stimulus edge length?

8 degrees

Toad fun facts

100

Do toads have a monocular or binocular vision?

MONOCULAR VISION 

200

What time of day do Bufo Bufo toads hunt?

They hunt at night

300

What shape are Bufo Bufo’s pupils? 

Horizontal