From the Eyes to the Brain

From the Eyes to the Brain Once the optical system projects an image on the retina, a series of electrochemical interactions begins. The photoreceptors (cones and rods) transform the image (light energy) into electric messages. These messages are transmitted through neurons (nerve cells). Magnified rods and cones!

The neurons converge at the optic disk where the optic nerve (a thick bundle of nerves) is connected to the eye. Both optic nerves extend into the skull and join at a point called the optic chiasm.

From the Eyes to the Brain (cont.) The optical nerves continue to the back of the brain. Processing of the images begin in the lateral geniculate nucleus (LGN) The images end up in the back of the brain at the visual cortex. Images from both eyes are processed together to form a complete image.

Animation http://www.sumanasinc.com/webcontent/ animations/content/visualpathways.html

Into The Brain

Three Main Parts Cerebrum: The large wrinkled portion that makes up most of the brain. Contains majority of processing happens 2/3 of brain mass Convoluted= Folds and grooves Brain stem--------------

Parts of the Brain (cont.) Cerebellum: underneath the cerebrum, this smaller part of the brain is found in the center of the brain. Controls movement and balance

Parts of the Brain (cont.) Brain stem: An extension of the spinal cord. It is found in front of the cerebellum and below the cerebrum. Controls basic functions like: heart rate, breathing, sleeping and eating

Hemispheres Has two halves or hemispheres– Left and Right These two halves look symmetrical and communicate with each other via the corpus collosum.

Lobes of the Brain Organized into four major lobes Frontal: behind the forehead. Planning, higher order thinking, logical, reasoning, personality, emotional response, thinking and planning ahead

Lobes of the Brain (cont.) Temporal: Along the side in from the ear. Processing of sensory input, supports speech and language

Lobes of the Brain (cont.) Occipital: In the back. Processes Visual information

Lobes of the Brain (cont.) Parietal: On the top Interacts brain and body, touch, movement

Sensory and Motor Cortex Motor Cortex- controls voluntary movement Sensory Cortex- processes body touch and sensations

Internal Structures Optic Track Pituitary Gland Hippocampus Cerebellum Brain Stem Medulla Pons Mid Brain Cerebrum Cerebral Cortex Corpus Callosum Amygdala Optic Track Pituitary Gland Hippocampus Cerebellum Hypothalamus Pons

Brainstem Oldest part of brain Life without it? 17

Brainstem Medulla Pons Thalamus/ Midbrain Text

Medulla Controls heartbeat and breathing Close your eyes and be quiet Why is this important?

Pons Coordinates movement Activity 20

Thalamus The “Hub” Receives information from all senses (except smell) and sends it to different lobes of the brain

Corpus Callosum Connects Left and Right hemispheres Can you remember what views of the brain these are? 24

Internal Structures Hypothalamus- hunger, thirst, temperature 32

Internal Structures Amygdala- aggression and fear 33

Internal Structures Hippocampus- memory 34

Internal Structures Pituitary Gland- controls hormones

Views of the Brain PET CAT Which view is used in each of these pictures?

How Can We Look At The Brain? Looking at a living brain without opening the skull is done through a scan. Types of scans: Computerized axial tomography (CAT) – produced with a computerized x-ray device.

Magnetic resonance imaging (MRI)- As a person is slid into a tunnel-shaped scanner, a magnetic field surrounds them. Radio waves are beamed to the area.

Electroencephalography (EEG)- measures electric activity in the brain by attaching electrodes to a patient’s head.

Positron emission tomography (PET) – Low-dose radioactive isotope is detected by injecting a substance into the patient. This substance is detected in the brain by the scanner.

KWL

Final Project Describe what the major parts of the brain are doing while you are doing something you love. For example: biking, sleeping, swimming, listening to music, cooking, dancing, etc.... Worksheet will help you! Rubric will help you! Your teachers will help you! 15

Rubric 36

Example Project www.prezi.com