Institute on NeuroscienceION/Teach

Build-A-Brain!

This Is Your Brain

Middle English words for front, back, top and bottom

Directional Terms

Nonhuman animals are oriented differently

So are their brains

Frontal Lobe

• reasoning• planning • parts of speech• movement• emotions• problem-solving

Temporal Lobe

• Hearing or audition• memory

Parietal Lobe

perception related to:• touch• pressure• temperature• pain

Occipital Lobe

• Vision or sight

The Cerebrum

Lobes are only organized like this in the brains of mammals

Brain Stem & Spinal Cord

-Hypothalamus – the 4 F’s-Thalamus—sensory relay station

•Midbrain

•Hindbrain-Pons - ”bridge” (plus nuclei)-Medulla oblongata-Cerebellum

-Tectum -Processing visual and auditory stimuli -Lower vertebrates: vision-Tegmentum -basal ganglia: motor activity

•Diencephalon

The Cerebellum

•Functions:

coordination of balance, locomotion and movement

•Note:

All vertebrates have a cerebellum which varies in size depending on the class of animals

Brain Complexity & Surface Area

How does this brain compare to other vertebrate brain models?

•Convolutions = folds

•Increase surface area

•Reflect more complexity (in cerebrum and/or cerebellum only)

Vertebrate Brain Diversity• Brain diversity across

vertebrate classes

• Size of forebrain related to "intelligence" of species

• behavioral complexity?

• Compare across species to consider structure-function relations

• e.g. olf bulb or cerebellum

Vertebrate Brains and Brain Diversity

Brain Diversity & Adaptations

Understanding an animal’s behavior or how it interacts with its environment can help you make predictions about what its brain might look like

Knowing about an animal’s brain can help you make predictions about its behavior or sensory systems

Relative brain size is more important than overall brain size

Who has the best brain?

That depends on what you need it for.

Evolutionary increase in relative brain size.

• Humans and several other animals have much larger brains than expected, based on body mass.

• Ratio was named the “encephalization quotient”, by H. J. Jerison.

Hypothesized reasons: climate change eating fruit! improved vasculature neoteny

How are dog and cat brains different?

• Which do you think has a proportionally larger olfactory bulb?

• How about cerebral cortex? Which has more wrinkles (convolutions)?

• How about the cerebellum? Which is bigger? Which has more convolutions?

Dog vs. Cat

Brains and Behavior of Aquatic Mammals: A Comparison of Dolphins, Sea Lions and

Manatees

Comparison Porpoise Sea Lion Manatee

Class Mammal Mammal Mammal

Primary way to find food (forage)

echolocation visual tactile

Diet shrimp, fish fish sea grasses

Vocalizations complex -- mother-pup I.D.

Territorial no yes no

Dominance hierarchy yes yes no

Tricks Acrobatic/balance Acrobatic/balance --

Olfaction Lobes and nerves absent Pup I.D. probably

Cerebral cortex Guess! Guess! Guess!

Sea Lion

Bottle-nose Dolphin

Marine Mammal:Florida Manatee

Compare Marine Mammal Brains

Consider These BrainsForebrain/Cortex

Cerebellum(Coordination)

Midbrain(Visual)

What do these brains tell you about the behavior of these

animals?Forebrain/Cortex

Cerebellum(Coordination)

Midbrain(Visual)

Now Build Your Own Brain!• It can be a brain from a real or imaginary

creature

• Supplies: Play-Doh (at least four different colors), your imagination, and hands!

• What does the relative size of different brain regions say about the environment of the animal?