Biology and Behavior

1. Biology and Behavior Chapter 2 Part II

2. A Walk Through the Brain • The brain stem. • The cerebellum. • The thalamus. • The hypothalamus and the pituitary gland. • The amygdala. • The hippocampus. • The cerebrum and lobes of the cerebral cortex..

3. Mapping the Brain Web-site • http://www.howstuffworks.com/brain.htm/printable

4. The Brain Stem • Pons • involved in sleeping, waking and dreaming. • Medulla • responsible for certain automatic functions such as breathing and heart rate. • Reticular activating system (or formation) • arouses cortex and screens incoming information.

5. The Cerebellum • Regulates movement and balance. • Involved in remembering simple skills and acquired reflexes. • Plays a part in analyzing sensory information, solving problems and understanding words

6. The Thalamus • Relays sensory messages to the cerebral cortex. • Includes all sensory messages except those from olfactory bulb.

7. Pituitary Gland Hypothalamus and Pituitary Gland • Involved in emotions and drives vital to survival including fear, hunger, thirst, and reproduction. • Also regulates autonomic nervous system. • The pituitary gland is a small endocrine gland which releases hormones and regulates other endocrine glands.

8. The Amygdala • Responsible for arousal and regulation of emotion and the initial emotional response to sensory information. • Plays important role in mediating anxiety and depression.

9. The Hippocampus • Responsible for the storage of new information in memory. • Compares information with what the brain has come to expect about the world. • “Gateway to memory” because it enables us to navigate through the environment.

10. The Cerebrum • Largest brain structure. • Consists of upper part of brain and divided into two cerebral hemispheres which are connected by the corpus callosum. • In charge of most sensory, motor and cognitive processes. • Surrounded by cerebral cortex, a collection of several thin layers of cells (gray matter).

11. Lobes of the Cerebral Cortex • Occipital lobes (Latin-in back of head) • Visual cortex. • Parietal lobes (Latin-pertaining to walls) • Somatosensory cortex. • Temporal lobes (pertaining to the temples) • Memory, perception, emotion and auditory cortex. • Left lobe, Wernicke’s area. • Frontal lobes • Emotion, planning, creative thinking and motor cortex. • Left lobe, Broca’s area.

12. The Corpus Callosum • Millions of myelinated axons connecting the brain’s hemispheres. • Provides a pathway for communication between the hemispheres. • If surgically severed for treatment of epilepsy, hemispheres cannot communicate directly.

13. Cerebral Hemispheres

14. Are There “His” and “Hers” Brains? • After analyzing 49 studies of sex differences in brain anatomy, researchers found small differences between the two groups and larger differences within groups. • There does appear to be sex differences in lateralization of language. Males show left hemisphere activation only. Females, left and right. • There also appears to be differences in amounts of gray matter. Females have more.

15. Genes and Behavioral Genetics • Genes • The segments of DNA that are located on the chromosomes and are the basic units for the transmission of all hereditary traits • Chromosomes • Rod-shaped structures in the nuclei of body cells that contain all the genes and carry all the hereditary information • Zygote • A single cell formed from the union of 23 chromosomes from the male’s sperm and 23 chromosomes from the female’s egg

16. Genes and Behavioral Genetics • Sex-linked inheritance • Involves the genes on the X and Y chromosomes • In females, the harmful gene is offset by the gene that is not harmful • In males, if the single X chromosome carries a harmful gene, there is no offsetting gene on the Y chromosome because it is very small and carries only the genes needed to create the male body type

17. Electroencephalogram (EEG) • A recording of neural activity detected by electrodes.

18. Magnetic Resonance Imaging (MRI) • Method for studying body and brain tissue. • Magnetic fields align certain ions and compounds • When field is removed, these molecules release energy as radio waves • Computer calculates tissue density from radio waves. • Provides clear, 3D images.

19. Positron Emission Tomography (PET) • A method for analyzing biochemical activity in the brain, using injections of a glucose-like substance containing a radioactive element. • Active areas have increased blood flow. • Sensors detect radioactivity. • Different tasks show distinct activity patterns.

20. The Origin or the CAT Scan

21. The Lesson of Einstein’s Brain • Like any muscle, a life time of thinking can bulk up your brain as well!