Parts of the Brain

Three parts of the brain Hindbrain (lower) Mid brain Forebrain (upper)

Hindbrain Brain Stem: the center of involuntary actions: balance, breathing, heartbeat Medulla: monitors the body’s response to injury, blood pressure, and reflexes such as sneezing and laughing Reticular Activating System: Involved in sleeping and wakefulness Begins in hindbrain, rises thru midbrain

Hindbrain Pons: Relay station between cerebellum and cerebral cortex Regulating body movement, attention, sleep/alertness Cerebellum Responsible for movement, balance, and posture Coordination – if damaged, can cause someone to walk unsteady or fall

Midbrain Top inch of the brain stem Connecting station for nerve signals Contains part of the reticular activating system; passes signals from hindbrain to forebrain Involved in vision and hearing

Forebrain Limbic system Controls emotional response Hypothalamus: The size of a pea. Controls body temp. and regulates the pituitary gland Helps control hunger/thirst

Forebrain Thalamus Relays information from the body to the brain Gets back information that is sent to other parts of the brain and spinal cord Cerebrum 2/3 of brain, 70% of weight Divided into 2 hemispheres, each w/ 4 lobes covered by cerebral cortex (outermost “bark” of the brain)

Two hemispheres: right v. left The two hemispheres are connected by a bundle of nerve fibers called the corpus callosum Corpus callosum allows the two sides to communicate with each other

Four lobes of the brain Frontal located in the front of the brain, behind the forehead Core of a person’s personality and emotional reactions Socially appropriate behavior: Judgment Problem-solving Impulse control Reasoning Memory and ability to plan

Four lobes of the brain Temporal Located behind your ears Responsible for hearing, music, understanding speech, and memory for nonverbal events Memory Hearing Recognition Perception Hearing language: Right – non, left - verbal

Four lobes of the brain Parietal Lobe Located on the top of your head Your left parietal lobe makes sense of info coming in from the right side of your body; right does the opposite. Helps you understand body senses, pressure, heat, cold pain, reading, thinking

Four lobes of the brain Occipital lobe Located on the back of your head Responsible for vision – left controls right vision, right controls left vision Damage can cause blindness

Endocrine System The nervous system’s partner in controlling and coordinating the body’s functions Hormones: Chemical messengers which are sent into the bloodstream and are responsible for maintaining normal growth, sexual development, and metabolism.

Endocrine System Glands: the organs and tissues scattered throughout the body that produce hormones.

Glands Pituitary Gland Controlled by hypothalamus Often called the master gland b/c its hormones influence many of the other endocrine glands. Growth hormone

Glands Thyroid Gland Produces energy the body can use from nutrients An overactive gland will cause you to feel nervous and jittery An under-active gland will make you feel slow and depressed (and likely gain weight)

Glands Adrenal Gland Influences metabolism and physical characteristics Body shape Hairiness Produces adrenaline In response to stress, fear, and anger