The Brain

•The Developing Brain

•Parts of the Brain & their Function

•Lobes of the Brain

•Split Brain Studies

•Environment’s affect on Brain

•Brain Plasticity

Early Brain Mapping: Phrenology

• By studying the lumps on a person’s skull, early scientists thought that they could map out the brain.

• Not accurate • But did lead to the

idea of localization of brain functions.

The Brainstem

Hindbrain Structures

• Cerebellum

• Brainstem– medulla

– reticular formation

– pons

Medulla•Breathing•Heart rate•Digestion•Other vital reflexes

–swallowing

–coughing

–vomiting

–sneezing

Reticular Formation

• Network of neurons in the brainstem (and thalamus)

• Sleep and arousal• Attention

Pons

• Helps coordinate movements on left and right sides of the body– e.g., postural

reflexes which help you maintain balance while standing or moving

Cerebellum• Word actually means

“little brain”• Coordinated, rapid

voluntary movements– e.g., playing the piano,

kicking, throwing, etc.

• Place where procedural memories are kept. – e.g. how to ride a bike,

swim

• Lesions to cerebellum– jerky, exaggerated

movements– difficulty walking– loss of balance– shaking hands

Midbrain Structures

Middle Region involved in visual & auditory

processing.

Early warning system gets you ready for flight

or fight

Forebrain Structures

• Thalamus• Limbic

System• Cortex

Thalamus• Relay station in

brain• Processes most

information to and from higher brain centers

• Like the Post Office taking incoming messages and delivering them

The Limbic System

• Hypothalamus

• Amygdala

• Hippocampus

Parts of the Limbic System

Amygdala• Emotional

Center of the Brain.

• Deals primarily with fear & aggression.

Amygdala and Emotion

• Identify emotion from facial expressions

• Plays a role in fear & aggression

Amygdala damage makes this task difficult

(click on picture to advance photos)

Parts Of The Limbic System

Hippocampus• Helps us form

new memories.

• What happens when this is damaged? View the video of Clive Wearing.

Parts of the Limbic System

Hypothalamus

• Provides us with pleasurable feelings for doing the things that keep our species alive.

Hypothalamus• Involved in the 5 F’s

– 1. Food/Thirst,

– 2. Flight,

– 3. Fight,

– 4. Furnace (Temperature)

– 5. Fornication

– sexual behavior

– hunger, thirst

– sleep

– water and salt balance

– body temperature regulation

– circadian rhythms

– role in hormone secretion

Hypothalamus – Pleasure Center of the Brain

• Rat with an electrode implanted in a reward center of its hypothalamus, See some actual footage of this.

• Rat readily crosses an electrified grid, accepting the painful shocks, to press a lever that sends electrical impulses to its "pleasure centers."

• How often did the rat press the lever in an hour?• 7,000 times!!! It finally collapsed from exhaustion (Olds

1958)

Hypothalamus and Hormones

Hypothalamus releases hormones or releasing factors which in turn cause pituitary gland to release its hormones

Feedback Loop lets brain know when to start & stop secreting hormones

DAILY

DOUBLE

What are the 5 F’s that the Hypothalamus influences?

1. Food/Thirst

2. Flight

3. Fight

4. Furnace – Body temperature

5. Fornication