The Brain (cont.) Somatosensory cortex & primary motor cortex Cerebral cortex= processes thought, vision, language, memory and emotion 80% of brain weight 70% of the neurons in the CNS 2 hemispheres (left and right) Hemispheres are divided into 4 lobes Association Areas= receive and send messages to/from the body Somatosensory cortex & primary motor cortex

The Brain (cont.) Lobes of the brain: Occipital lobe= (back) visual information Temporal lobe= regulates hearing, balance, & certain emotions Parietal lobe= receives sensory information from throughout the body Frontal lobe= responsible for voluntary movement; important for attention & appropriate emotional experiences

Pinky and the brain

The Brain (cont.) Frontal Lobe Damage Phineas Gage personality

Phineas Gage Clip

Hemispheric Specialization Right half and left half connected by corpus callosum Close communication Coordinated unit Functionally isolated If cut: left receives right info only and right receives left info only

Severed Corpus Callosum Clip

Hemispheric Specialization Language ability primarily in the left hemisphere Analytical, logic, rationalizing Right hemisphere excels at visual and spatial tasks Note: not everyone shows the same pattern of differences May be greater in men than in women LEFT BRAIN or RIGHT BRAIN test

Language Aphasia is an impairment of language, usually caused by left hemisphere damage either to Broca’s area (impaired speaking) or to Wernicke’s area (impaired understanding).

Electroencephalogram (EEG) An amplified recording of the electrical waves sweeping across the brain’s surface, measured by electrodes placed on the scalp. AJ Photo/ Photo Researchers, Inc.

PET Scan PET (positron emission tomography) Scan is a visual display of brain activity that detects a radioactive form of glucose while the brain performs a given task. Courtesy of National Brookhaven National Laboratories

The Spinal Cord There is no clear boundary between the brain and spinal cord It is our “communication superhighway” by connecting brain to rest of the body Motor neurons (descending) Sensory neurons (ascending) Instantaneous responses

Peripheral Nervous System

Peripheral Nervous System Somatic Nervous System: The division of the peripheral nervous system that controls the body’s skeletal muscles. Autonomic Nervous System: Part of the PNS that controls the glands and other muscles. Crucial to body functions

Autonomic Nervous System Sympathetic Nervous System: Division of the ANS that arouses the body, mobilizing its energy in stressful situations. Parasympathetic Nervous System: Division of the ANS that calms the body, conserving its energy.

Autonomic Nervous System (ANS) Sympathetic NS “Arouses” (fight-or-flight) Parasympathetic NS “Calms” (rest and digest)

The Endocrine System The Endocrine System is the body’s “slow” chemical communication system. Communication is carried out by hormones synthesized by a set of glands. Preview Question 4: How does the endocrine system-the body’s slower information system-transmit its messages?

The Endocrine System The nervous system and the endocrine system work together in constant chemical conversation. Main difference between the two is SPEED

Hormones Hormones are chemicals synthesized by the endocrine glands that are secreted in the bloodstream. Hormones affect the brain and many other tissues of the body. For example, epinephrine (adrenaline) increases heart rate, blood pressure, blood sugar, and feelings of excitement during emergency situations.

Pituitary Gland Is called the “master gland.” The anterior pituitary lobe releases hormones that regulate other glands. The posterior lobe regulates water and salt balance.

Thyroid & Parathyroid Glands Regulate metabolic and calcium rate.

Adrenal Glands Adrenal glands consist of the adrenal medulla and the cortex. The medulla secretes hormones (epinephrine and norepinephrine) during stressful and emotional situations, while the adrenal cortex regulates salt and carbohydrate metabolism.

Gonads Sex glands are located in different places in men and women. They regulate bodily development and maintain reproductive organs in adults.

Gonad Hormones Androgen (classified as male) Estrogen (classified as female) BOTH sexes produce BOTH hormones, but one typically dominates Testosterone linked to aggressive behavior Male violence 15-25 years old (testosterone at highest) Levels differ between married and unmarried men & those who have children (or don’t)

Genetics Study of how living things pass on traits from one generation to another. Genes= basic units of inheritance Carried by chromosomes in pairs 23 pairs Females XX Males XY DNA is the only molecule that can replicate itself Dominant & Recessive Genes Don’t cause behavior but affect development

Human Behavior Genetics Family studies if genes influence a trait, close relatives should share that trait Schizophrenia Twin studies Identical Twins= develop from single ovum (genetic identical) Fraternal Twins= develop from 2 separate eggs

Evolutionary Psychology Natural selection= organisms who adapt better survive and pass on genes Reproduce “Prewired” EX- Language acquired about the same time across cultures Critics say: “just so” ideas tend to generalize and justify the status quo

Complete the graphic organizer identifying 3 theories of individual development