Brain I: Neuroanatomy

Brian J. Piper, Ph.D.

Goals

• Major Brain Areas• Neuroimaging

Spinal Cord

• Divided into regions:– Cervical– Lumbar

• Function– Motor– Sensation

Brainstem

The Medulla is the base of the

brainstem that controls heartbeat

and breathing.

Example: SIDS

Beneath Skull

• Dura: thick/tough layer• Arachnoid: contains blood vessels• Pia: thin layer

______ lobe

Match Color

Sensory Areas

Description of 3-Dimensional Space

• Coronal: – section from ear to ear, like a loaf of bread– most commonly used for animal research

• Sagital: – section from front to back– mid-sagital shows brain with left and right

cortex separated • Axial:

– section that parallels horizon – Common for showing humans

2.2

Different Planes

Anatomical Terminology

Functions of Different Cortical Areas

• Frontal: cognition, executive function• Temporal: hearing• Occipital: vision• Parietal: integration of sensory information

AnteriorPosterior

Dorsal

Ventral

Corpus Callosum

• Fibers that connect left and right cortex

Fornix

Cingulate Gyrus

• Tissue surrounding corpus collosum– Anterior– Posterior

Cerebellum (a mid-saggital)

• Located below the occipital cortex

• Important for motor function

• Site of action of alcohol

CC

BS

Cerebellum

• Located below the occipital cortex

• Important for motor function

• Site of action of alcohol

CC

BS

Thalamus

• Located in the center of the brain

• Major relay center, information from spinal cord goes to thalamus, thalamus has many connections to the cortex

Hippocampus

• Bilateral structure• Hippocampus is greek

for seahorse• Essential for memory,

especially spatial memory

• Effected by long term alcohol exposure

http://www.bris.ac.uk/Depts/Synaptic/info/pathway/hippocampal.htm

Hippocampus: Coronal

Box a contains hippocampus: CA = cornu ammonisDG = dentate gyrusCC = corupus collosum

cc

1.2

Amygdala

The Amygdala consists of two lima bean-sized

neural clusters linked to the emotions of fear and

anger.

Brain Areas Important for Hormone Control

• Pineal Gland– Very small subcortical structure– Releases the hormone melatonin

• Hypothalmus– Hypo = “below” therefore located

under thalamus– Regulates activity of Pituitary– Pituitary communicates with

other endocrine glands (e.g. testes)

– Important for steroids

Rene Descartes

Ventricles: Contain CSF

Abnormal Ventricles

http://www.omsi.edu/visit/life/aging/brainText.cfm

Hypothalamus

• Paraventriclar Nucleus: stress response• Suprachiasmatic Nucleus (SCN): circadian

rhythms• Mammillary body: #5

Neuroanatomy Video (1.5 min)

• http://www.youtube.com/watch?v=Li5nMsXg1Lk

Animal Research

=

?Very helpful, but ….

Hippocampus Comparison

More brainsrat & dog

(Thalamus

A BC

D

E

F

G

H

IJ

K

L

and sheep brain

Cranial Nerves

• I. Olfactory: smell (S)• II. Optic: vision (S)• III. Oculomotor: pupil construction (M)• IV. Trochlear: eye movement (M)• V. Trigeminal: face & teeth (S), jaw (M)• X. Vagus: heart (SM), autonomic nervous system

Brain Imaging

• Can provide information about anatomy (structure) or physiology (function)

• Imaging procedures differ in their:– Spatial resolution: the ability to differentiate nearby brain

regions– Temporal resolution: the ability to differentiate brain

activity at different times

For more about brain imaging and drug abuse goto:http://www.nida.nih.gov/NIDA_Notes/NNVol11N5/Basics.html

Electroencephalography (EEG)

• Developed by Hans Berger in 1929

• Electrodes are placed on the surface of the skull

• Electrical activity from the cortex is recorded

1873-1941

Time

Computed Tomagraphy (EMI scan, axial)

• Developed in the 1970’s• X-ray beams are passed

through the head• A 2 or even 3-

dimensional structural map is created

For more information about CT, goto:http://en.wikipedia.org/wiki/Computed_axial_tomography

1.7

Gr: tomos (slice) & graphein (to write).

Positron Emission Tomography (PET, another axial)

• Radioactive material is injected into the blood

• Scanner records the radioactivity (positron) in different parts of the brain

• Provides information about function

• Very useful for research

For more detailed information about PET, goto: http://en.wikipedia.org/wiki/Positron_emission_tomography

1.7

Figure 2. Brain Glucose Metabolic Images Showing Axial Planes at the Level of the Orbitofrontal Cortex

Volkow, N. D. et al. JAMA 2011;305:808-813

Copyright restrictions may apply.

Functional Magnetic Resonance Imaging (fMRI)

• A cylindrical magnet creates a magnetic field

• A sensor records blood flow and brainactivation

• Can also be used for just structure• White matter• Gray matter• Ventricle

2.2

Comparison of Imaging Techniques

Procedure Measures Brain:

Advantage Disadvantage

EEG Function Excellent temporal resolution (msec)

Measures only from brain surface

CT Structure Found in many hospitals

Some radiation exposure

PET Function Wide variety of uses

Poor temporal resolution (min), Poor spatial resolution (cm)Radiation

fMRI Function Good temporal resolution (sec), Good spatial resolution (0.5cm)

Patient cannot have metal implants

4.7

The Brain

Techniques to Study the Brain

A brain lesion experimentally destroys brain tissue to study

animal behaviors after such

destruction. Hubel (1990)

What plane?

Sarah Tappon, 8/5/2009

Sarah Tappon, 8/5/2009

What is the impact of …?

Example Brain Research

• Brain Development: Healthy, Hyperactive & Childhood Schizophrenia

• http://videocast.nih.gov/launch.asp?15762• Juddith Rappaport, M.D.• 2:40 up 37:50• Jargon

– Myelination: formation of white matter (myelin)– Intramural: part of the National Institutes of Health in DC– Prospectively: to follow forward in time– Apolipoprotein E: gene that is associated with Alzheimer’s Disease– Heritability: extent that a trait is due to genetic factors in a sample