Although when placed side by side, the bullfrog brain may look like the head of a pin compared to the human brain, the little amphibian's mind is well equipped with the tools he needs to get around, including several sensory components that manage smell, vision and more.
Outline of the Frog Brain
The bullfrog brain consists of more than a dozen sections controlling actions, movements, reactions to the environment and more. These sections include four different ventricles, which exchange messages and brain fluids; the aqueduct of Sylvius, which connects some of the ventricles with one another; the thalamencephalon, which helps relay messages; the medulla oblongata, which contains control centers for a frog's heart and lungs; and sensory components responsible for smell, hearing, taste, touch and other senses.
At the Forefront: Two Olfactory Lobes
Two olfactory lobes are located at the front of the brain, and are responsible for controlling sense of smell. Unlike many species, frogs don't often use them to detect food. Instead, their olfactory lobes help recognize familiar breeding grounds, or a frog's home pond. They can also detect chemical changes in the air, including scents of predators. Along with olfactory lobes, bullfrogs have an organ on the roof of their mouths called the Jacobson's organ, which they use to locate food.
Right Nearby: The Cerebral Hemisphere
Directly behind the olfactory lobes in a bullfrog's brain is the cerebral hemisphere. This part of the brain controls the activity of the rest of the brain's components. Appearance and size vary dramatically among species, and in frogs, the cerebral hemispheres are small bumps on the brain stem. The cerebral hemisphere is responsible for a number of functions, including motor and sensory control, perception, responding to the external environment and connecting the brain to the spinal cord.
Other Sensory Tools
The frog's brain also has other sensory components, further back than the two olfactory lobes, Jacobson's organ and the cerebral hemisphere. For example, the optic lobe is around the middle part of the brain, and is responsible for a frog's vision. Frogs have pretty good vision and are able to see in color, low light and across far distances. They also have a type of mirroring capability in the back of their eyes, which lets them reflect light at night.
Sarah Whitman's work has been featured in newspapers, magazines, websites and informational booklets. She is currently pursuing a master's degree in nutrition, and her projects feature nutrition and cooking, whole foods, supplements and organics. She also specializes in companion animal health, encouraging the use of whole foods, supplements and other holistic approaches to pet care.