Today is a great day to learn about your BRAIN!!!

Human Brain

How do we know about the brain? EEG- electrical activity of brain CAT- 3D images MRI- image of radio waves/ Hydrogen atom energy PET- visual image of trace chemical activity after injection of radioactive substance

EEG

EEG

CAT

CAT

MRI

MRI

PET

PET

PET

Parts of the Brain

Cerebral Cortex The body’s ultimate control and information processing center Covers the brain’s lower level structures Contains an estimated 30 billion nerve cells Divided into four lobes

Frontal Lobes The portion of the cerebral cortex lying just behind the forehead Is involved in making plans and judgments

Occipital Lobe The primary visual processing area Located in the back of the head

Parietal Lobes Regions available for general processing, including mathematical reasoning Designated as the association lobes Behind the frontal lobes Processes taste, smell, and feeling Motion – motor cortex

Frontal Lobes The portion of the cerebral cortex lying just behind the forehead Is involved in making plans and judgments

Motor Cortex Area at the rear of the frontal lobes Controls voluntary movement Different parts of the cortex control different parts of the body. The motor cortex in the left hemisphere controls the right side of the body and visa versa.

Somatosensory Cortex Located in the front of the parietal lobes Registers and processes body senses Soma is Greek for “body.”

Parietal Lobes Regions available for general processing, including mathematical reasoning Designated as the association lobes Behind the frontal lobes

Temporal Lobes Includes the auditory cortex where sound information is processed Located roughly above the ears

Cerebellum Latin for the “little brain” Located in the rear of the brain Helps coordinate voluntary movements and balance If damaged, the person could perform basic movements but would lose fine coordination skills.

Cerebrum Longest part of brain Two hemispheres Responsible for voluntary movement, speech, emotion, memory intelligence and memory processing

Brainstem The oldest part of the brain Is responsible for automatic survival functions Located where the spinal cord swells and the brain just begins

Midbrain The MIDBRAIN is also responsible for behaviors associated with hearing and sight Pupil dilation and eyeball movement

PONS The PONS is responsible for helping to regulate breathing, to help with sleep and wake cycles, and controls facial expressions

Medulla The base of the brainstem Controls life-supporting functions like heartbeat and breathing Damage to this area can lead to death.

Limbic System A ring of structures around the thalamus; at the border of the brainstem and cerebral cortex Helps regulate memory, aggression, fear, hunger, and thirst Includes the hypothalamus, hippocampus, and amygdala

Thalamus Sits atop the brainstem The brain’s sensory switchboard -- directs messages to the sensory receiving areas in the cortex Thalamus is Greek for “inner chamber.”

Hypothalamus Located directly under the front of the thalamus Regulates eating, drinking, body temperature, and the fight or flight reactions to stress Plays a role in emotions, pleasure, and sexual function

Limbic System A ring of structures around the thalamus; at the border of the brainstem and cerebral cortex Helps regulate memory, aggression, fear, hunger, and thirst Includes the hypothalamus, hippocampus, and amygdala

Hypothalamus Located directly under the front of the thalamus Regulates eating, drinking, body temperature, and the fight or flight reactions to stress Plays a role in emotions, pleasure, and sexual function

Hippocampus Wraps around the back of the thalamus Plays a role in processing new memories for permanent storage Looks something like a seahorse –Hippo is Greek for “horse.”

Amygdala Two almond shaped structures Controls emotional responses such as fear and anger

Hemispheric Differences Module 8: The Brain

Hemispheric Differences “Left-brained” and “right-brained” debunked Brain is divided into two hemispheres but works as a single entity. Both sides continually communicate via the corpus callosum, except in those with split brains.

Hemispheric Differences: Language and Spatial Abilities Module 8: The Brain

The Brain’s Left Hemisphere For most people, language functions are in the left hemisphere. For a small percentage of people, language functions are in the right hemisphere.

Broca’s Area Located in the frontal lobe and usually in the left hemisphere Responsible for the muscle movements of speech If damaged the person can form the ideas but cannot express them as speech

PET Scan of Broca’s Area

Wernicke’s Area Located in the temporal lobe Involved in language comprehension and expression; our ability to understand what is said to us Usually in the left temporal lobe

PET Scan of Wernicke’s Area

The Brain’s Right Hemisphere Houses the brain’s spatial abilities Our spatial ability allows us to perceive or organize things in a given space, judge distance, etc. Helps in making connections between words

Brain Plasticity Module 8: The Brain

Plasticity The ability of the brain tissue to take on new functions Greatest in childhood Important if parts of the brain are damaged or destroyed

Let’s look at the brain another way Let’s look at the brain another way

3 main parts of the Brain 1.Hindbrain 2.Midbrain 3.Forebrain

There are three main parts in a human brain: 1 st : The Hindbrain It controls basic life functions

The Hindbrain 1) Medulla: blood pressure, heart rate, breathing

2) Pons: Connects hindbrain w/ midbrain & forebrain = facial expressions

3) Brainstem beginning where the spinal cord swells as it enters the skull responsible for automatic survival functions

4) Reticular Formation in the brainstem important role in controlling arousal

5) Cerebellum Reflexes balance sequential movement

2 nd Midbrain: It controls sensory info

3 rd Forebrain Thought and Reason

1) Thalamus central relay station for incoming and outgoing messages (sensations)

2) Hypothalamus regulates basic needs & emotions Food, water, sex for survival of species

3) Amygdala Aggression & Anger Emotional Memories

4) Hippocampus Formation of New Memories

5) Cerebral Cortex Thought. Outer surface of 2 Cerebral Hemispheres-

6) Cerebral Hemispheres- Left- names, complicated math, speaking Right- faces, basic functions, drawing

7) Divided into Four Lobes –A) Occipital Lobe: –Receives visual info »Primary Visual Cortex: process visual info

B) Temporal Lobe: receives Hearing info & Balance »Primary Auditory Cortex: process auditory info

C) Parietal Lobe: Receives Sensory info »Primary Somatosensory Cortex: process sensory info

D) Frontal Lobe: receives Voluntary movement, attention information »Primary Motor Cortex: process voluntary movement info

8) Corpus Callosum Nerves that hold hemispheres together, and transfer info from left/right

Corpus callosum

Language in the Brain (Left Hem) Broca’s area Speaking Wernicke’s area understanding

The End