Body and Behavior Systems of your body

The Nervous System The nervous system (NS) sends messages from your brain to your body. The Brain and Spinal cord Neurons- the long, thin cells that constitute the structural and functional unit of nerve tissue, along which messages travel to, from, and within the brain Synapses are the the gaps between individual nerve cells

The brain monitors what is happening inside and outside the body by receiving messages from receptors- cells that gather information. One end of the neuron receives the message, the other end transmits the message chemically to the next neuron. Neurotransmitters, chemicals that can excite the next neuron or stop it from transmitting.

Somatic Nervous System (SNS)- the part of the peripheral nervous system that controls voluntary activities. Autonomic nervous system (ANS)- the part of the NS that controls involuntary activities (heart beat, stomach activity) 2 parts of ANS- Sympathetic NS- prepares the body for dealing with emergences or strenuous activity (speeds up heart, restricts arteries and relaxes to help blood flow to the muscles) Parasympathetic NS- works to conserve energy and to enhance the body’s ability to recover from strenuous activity (Reduces heart rate and blood pressure)

The NS is divideded into 2 parts: The Central Nervous System (Brain and Spinal Cord) and the smaller branches of the nerves that reach the other parts of the body (peripheral NS). More than 2/3 of body’s neurons are in the brain. All parts of NS are protected- brain by the skull, Spinal cord by the vertebrate, peripheral nerves by layers of sheathing.

The brain is composed of 3 parts Part 1- The hindbrain- the rear or base of the skull Includes the medulla and the pons Medulla controls breathing and other reflexes Pons- controls balance, hearng and other functions Cerebellum-located behing the spinal cord contrils posture and balance

Part 2- the midbrain- a small part of the brain above the pons that integrates sensory information and relays it upwards The medulla, pons and midbrain compose most of the brain stem, and the Reticular activating system which alerts the rest of the brain to incoming signals

Part 3- forebrain- located above the brains central core, includes the thalamus (integrates sensory input) and the hypothalamus (monitors emotions, sleep and other bodily processes) “higher” thinking processes are house in the forebrain Outer layer of forebrain consists of the cerebral cortex- gives you the ability o learn and store complex and abstract information, and to project your thinking into the future. Allows you to see, read, and understand (Conscious thinking processes) The inner layer is the cerebrum

Lobes- are the different regions of the brain Some areas o f the cortex reveice information from the skin senses and from muscles. The ammount of brain tissue connexted to any given body part determines the sensitvity of that area, not its size. Somatosensory cortex- the part that receives information. The motor cortex sends information to control body movement; its also divided according to need

Some parts of the the lower brain (like the thalamus) filter out all of the most important messages The frontal lobes control creativity and personality, they enable people to be witty, sensitive, or easy going The case of Phineas Gage

Left Brain vs Right Brain thinkers The cortex is divided into 2 hemispheres. They are connected by a band of nerves called the corpus callosum, which carries messages back and forth between the two. The left hemisphere controls the right sife od the body and the right hemisphere controls the left side of the body

Left Brain characteristics 1- rational thinker 2- sequential 3- structured/planned 4- make objective judgments 5- prefers talking and writing 6- time-oriented 7- thinks concretely 8- controls feelings 9-is logical 10- looks for differences 11- needs to be in control

Right Brain Characteristics 1- intuitive 2- holistic 3- spontaneous 4- makes subjective judgments 5- prefers drawing and working with objects 6- ignores deadlines 7- prefers the elusive, uncertain 8- lets feelings go 9- is analogic 10- looks for similarities 11- takes more risks