The Human Brain

Tools for Viewing Brain Structure and Activity

EEG Electroencephalogram measures electrical

currents across the brain

Measure brain activity

Tools for Viewing Brain Structure and Activity

CT scan Also called a CAT scan Computerized axial

tomography X-ray of brain tissue Shows brain structure

Tools for Viewing Brain Structure and Activity

PET scan Positron Emissions

Tomography Patients drinks

radioactive glucose and image shows areas of brain activity.

Tools for Viewing Brain Structure and Activity

MRI Magnetic Resonance

Imaging Exposes brain to

magnetic field Shows brain structure

Tools for Viewing Brain Structure and Activity

fMRI functional MRI Uses magnetic field Not harmful Shows brain structure

and activity

Make a Venn Diagram:

SHOWS STRUCTURE

SHOWS FUNCTION

Types of Neurons

Sensory Neurons – Afferent Neurons

Carry the message from the sense organs to the CNS

Interneurons Make up the CNS

Motor Neurons – Efferent Neurons

Carry the message from the CNS to the muscles or glands

Remember – SAME (sensory = afferent, motor = efferent)

The Brain

Gray matter – areas of the CNS with high concentrations of cell bodies; outer surface of cerebrum (cerebral cortex)

White matter – areas of the CNS with mostly myelinated axons; inner part of cerebrum

Glial cells – cells in the brain that nourish and protect neurons

10 Facts about the Brain

Brain Stem

Structure Location Function

Medulla where spinal cord meets the skull

controls heartbeat and breathing

Pons above the medulla this also controls involuntary functions.

Reticular Formation

bundle of nerves running through the brainstem

controls arousal; filters irrelevant background information from senses; modulates pain.

Thalamus

Thalamus

Pair of egg-shaped organs above the brainstem

receives information from the senses (EXCEPT FOR SMELL) and relays it to the rest of the brain.

Cerebellum

In the rear of the head, behind the brainstem

Controls balance and coordination

Limbic System

Structure Location Function

Amygdala two almond shaped structures

influence fear and aggression

Hypothalamus below the thalamus

regulates hunger, thirst, body temp, sex, fight-or-flight; triggers the pituitary (the “master gland”); reward center

Hippocampus behind the amygdala

memory

Cerebral Cortex

Controls information processing; wrinkled to increase surface area

Composed of 8 lobes (4 on each side)

Frontal Lobes

Broca’s aphasia

The discovery of Broca's area

motor cortex

part of brain that controls voluntary movement)

Broca’s area

needed for forming words; located in left hemisphere only

Association areas

in this region – judgment, planning, processing new memories

Parietal Lobes

Located on the top and rear of head

sensory cortex part of brain that registers and processes tactile information

angular gyrus left hemisphere only) which is involved in converting written words into sound

Occipital Lobes

Located in the back of the head

Contains the visual cortex

Temporal Lobes

Located on the sides of head, above ears

Receives and processes auditory information

Wernicke’s aphasia

Wernicke’s area left hemisphere only) - part of brain involved in understanding language

Corpus Callosum

bundle of nerves connecting the left and right hemispheres

Brain Story

Name that brain part