accidents eeg lesions and functio nal mri cat petmri

The Brain

The Brain and Central Nervous System

How do we study the Brain??

Accidents

EEG

Lesions and Functional

MRI

CAT

PET

MRI

Accidents Phineas Gage Story

Personality changed after the accident.

What does this tell us?

Phineas’s frontal cortex (higher thinking) was severed from the part of the brain in charge of emotions.

Lesions Removal or destruction of some part of the brain.

Frontal Lobotomy

Electroencephalogram

EEG Detects brain

waves through their

electrical output.

Used mainly in sleep research.

Computerized Axial Tomography

CAT Scan

CAT(3 Words)

3D X-Ray of the brain.

Good for tumor locating, but tells us nothing about function.

Magnetic Resonance Imaging MRI More detailed picture of

brain using a magnetic field to knock electrons off axis.

Takes many still pictures and turns images into a movie like production.

Positron Emission Tomography PET Scan

Measures how much of a chemical the brain is using (usually glucose consumption).

Functional MRI

Combination of PET and MRI

Brain Structures:

1. Hindbrain2. Midbrain3. Forebrain

Cerebral Cortex (part or

forebrain)

Brain Structures:Hindbrain:

Medulla Oblongata Located just above the spinal cord.

Involved in control of blood pressure heart rate breathing.

Brain Structures:Hindbrain:

Cerebellum Controls our

balance and fine movement skills

Brain Structures: Midbrain

Coordinates simple movements with sensory information.

Most important structure in Midbrain is the Reticular Formation: controls arousal and ability to focus our attention.

Brain Structures: Forebrain

What makes us human. Largest part of the brain. Made up of the Thalamus,

Limbic System and Cerebral Cortex.

Brain Structures: Forebrain

Thalamus

Receives sensory signals from the spinal cord and sends them to other parts of the forebrain.

Brain Structures: Forebrain

The Limbic SystemEmotions, our most basic reactions, are generated in the Limbic system along with the many appetites and urges that help us behave in such a way to survive. For instance, the Amygdala, is the place where fear is registered and generated.

Brain Structures: Forebrain

Hypothalamas Maybe most

important structure in the brain.

Controls and regulates Body temperature Sexual Arousal Hunger Thirst Endocrine System

Brain Structures: Forebrain

Hippocampus

Involved in the processing and storage of memories.

Brain Structures: Forebrain

Amygldala

More involved in volatile emotions like anger.

Brain Structures: The Cerebral Cortex

Made up of densely packed neurons we call “gray matter”

Glial Cells: support brain cells.

Wrinkles are called fissures.

If you lay brain out it would be as big as a large Pizza 2000 pizza.

The Cerebral Cortex is made up of four Lobes.

http://www.google.com/imgres?q=lobes+on+a+brain&hl=en&safe=active&sa=X&qscrl=1&nord=1&rlz=1T4ADFA_enUS393US394&tbm=isch&prmd=ivns&tbnid=0qxi4Ttyo_YpyM:&imgrefurl=http://www.nlm.nih.gov/medlineplus/ency/imagepages/9549.htm&docid=ESrZP3QshA45NM&w=400&h=320&ei=kNw-TuyMK8ODsgKvz4kF&zoom=1&iact=hc&vpx=322&vpy=79&dur=2609&hovh=201&hovw=251&tx=156&ty=98&page=1&tbnh=120&tbnw=150&start=0&ndsp=9&ved=1t:429,r:1,s:0&biw=792&bih=528

Frontal Lobe

Abstract thought and emotional control.

Temporal Lobe

Process sound sensed by our ears.

Frontal LobeThe Broca and Wernick

Wernick-Decodes speech

Broca-Commands speech

Parietal Lobe

Contain Sensory Cortex: receives incoming touch sensations from rest of the body.

Occipital Lobe Deals with vision.

Contains Visual Cortex: interprets messages from our eyes into images we can understand.

Hemispheres

Left Right

logic

sequential tasks.

spatial

creative tasks.

Which way is the dancer spinning?

The Corpus Callosum

Connects the 2 hemispheres.

Split Brain Patients

Patients with severe epilepsy will have a procedure done that removes their corpus callosum.

Brain Plasticity The idea that the

brain, when damaged, will attempt to find news ways to reroute messages.

Children’s brains are more plastic than adults.