How the Brain Works The Facts Visually Explained by DK (z-lib.org)

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THE PHYSICAL BRAIN

The Brain Stem and Cerebellum 37

The cerebellum

Although the cerebellum appears to play a part in maintaining

attention and processing language, it is most associated with its

role in the regulation of body movement. Specifically, its role is

to convert the broad executive motor requests into smooth and

coordinated muscle sequences, error-correcting all the while.

It routes its outputs through the thalamus. At the microscopic

level, the cerebellum’s cells are arranged in layers. The purpose

of these layers is to lay down fixed neural pathways for all kinds

of learned movement patterns, such as walking, talking, and

keeping balance. Damage to the cerebellum does not result

in paralysis, but slow jerky movements.

The little brain

The cerebellum, a term that

means “little brain,” is a highly

folded region of the hindbrain

that sits behind the brain stem.

Like the cerebrum above it, the

cerebellum is divided into two

lobes. These are divided laterally

into functional zones.

Some artificial intelligences (AI)

use a system inspired by the

anatomy of the cerebellum.

AI programs itself by machine

learning. It does this with a

processor called a neural

network, where inputs find

their way by trial and error

through layers of connections,

a setup that mirrors the way

the cerebellum lays down

patterns for learned movements.

THE CEREBELLUM AND NEURAL NETWORKS

RE

AR

(^) V
IE
W
(^) O
F
(^) C
E
R
E
B
E
L
L
U
ANTERIOR M
LOBE

VERMIS

SPINOCEREBELLUM

L ATER AL

ZONE

Anterior lobe of

cerebellum receives

information about body

posture from spinal cord

Spinocerebellum compares

information about actual body

position to intended position of

planned movements and

modifies sequence as needed

ANTERIOR

LOBE

POSTERIOR

LOBE

VESTIBULOCEREBELLUM

Body movements

are coordinated

in posterior lobe

Vermis controls

most basic motor

patterns, such as

eye and limb

movements

Located on both

sides of cerebellum,

these zones are

involved in planning

sequences of

movements

Outer layer

composed of

gray matter

CE

RE

BE

LL

U

M

Vestibulocerebellum is involved in

head control, eye movements, and

maintaining balance through

information from the inner ear

KNOWLEDGE OF THE

CEREBELLUM WAS

ADVANCED BY

STUDYING BRAIN-

INJURED SOLDIERS

IN WWI

US_036-037_The_brainstem_and_cerebellum.indd 37 20/09/2019 12:32