February 2 2015 Chapter 2 The Biological Perspective Textbook Notes Section 1 Introduction The Biological Perspective Brain computer interfaces BCI with others The brain nerves and glands interact to control our feelings thoughts and behavior method of using the brains electrical activity to communicate Section 2 Neurons and Nerves Building the Network Neurotransmitters Their Functions 1 Acetylcholine Ach excitatory or inhibitory involved in arousal attention memory and controls muscle contraction 2 Norepinephrine NE mainly excitatory involved in arousal and mood 3 Dopamine DA excitatory and inhibitory involved in control of movement and sensations of pleasure released into the body when they go into panic mode 4 Serotonin 5 HT excitatory or inhibitory involved in sleep mood anxiety and appetite psychological health associated with depression Neurons and nerves The nervous system is a network of cells that carries info to and from all parts of the body neuroscience is the field of study that deals with the structure of the brain and components of the nervous system Brain is comprised of neurons and glial cells Glial cells provide physical and metabolic support to neurons communicate with other cells specific types have stem cell like properties 1 Oligodendrocytes produce myelin in the central nervous system 2 Schwann cells produce myelin in the peripheral nervous system myelin insulates axons and speeds up transmission of neural messages Neurons specialized cells in nervous system send and receive messages within that system Have specialized components 1 Dendrites receives messages 2 Soma cell body contains nucleus 3 Axon o Axon terminals synaptic knobs sends messages out to next neuron Have an electrical charge at rest the resting potential o Made possible by balance between ions in and outside of the cell o Membrane is semipermeable inside is negatively charged as compared to the outside o Change in electrical charge can result in an action potential cell fires inside becomes positive related to outside 1 Fire in an all or none fashion February 2 2015 2 Cell firing is dependent on sum of excitatory and inhibitory messafes received by the cell Are affected by neurotransmitters chemicals that have an effect on neurons Are separated by a gap called the synapse when nerve impulse reaches axon terminals neurotransmitter is released into synaptic space 1 Neurotransmitters NTs move across synapse and activate ion channel receptor sites on adjacent cells some NTs are agonistic excitatory others are antagonistic inhibitory 2 Neurotransmitter action stopped by exciting synapse neurotransmitters end back up in the releasing cell through reuptake or broken down by enzymes Section 3 The Nervous System and Endocrine Glands Nervous system two types 1 Central nervous system composed of the brain and spinal cord Brain interprets and stores info and sends orders to muscles glands and organs Spinal cord pathway connecting the brain and the peripheral nervous system 2 Peripheral nervous system transmits info to and from the central nervous system Autonomic nervous system automatically regulates glands internal organs and blood vessels pupil dilation digestion and blood pressure 1 Parasympathetic division maintains body functions under ordinary conditions saves 2 Sympathetic division prepares the body to react and expend energy in times of Somatic nervous system carries sensory info and controls movement of skeletal energy stress muscles The Spinal Cord Reflex 1 Flame stimulates pain receptors sensory neurons 2 Sensory neurons excite interneurons in the dorsal gray portion of the spinal cord interneurons and to the brain 3 Interneurons excite motor neurons in the ventral gray portion of the spinal cord motor neurons 4 Motor nerves exit the spinal cord excite the muscle and initiate a movement away from the flame spinal cord motor neurons muscle Functions of the parasympathetic and sympathetic divisions of the nervous system Sympathetic division the women is facing danger The sympathetic nervous system is active When a spider comes near the women 1 Pupils dilate grow and inhibits stops tear glands 2 Decreased salivation 3 Increased heart rate 4 Dilates bronchi lungs 5 Decreases digestive functions of the stomach pancreas and intestines 6 Prevents inhibits bladder contraction when you get scared you have to pee February 2 2015 Parasympathetic division the woman is relaxing after the removal of danger The parasympathetic division of her nervous system is active Removal of spider spider goes away from the women 1 Constricts pupil and stimulates tear glands 2 Slows heart rate 3 Increases salivation 4 Shrinks constricts bronchi lungs 5 Increases digestive functions of stomach pancreas and intestines 6 Allows bladder shrinkage contraction The endocrine glands secrete hormones directly into bloodstream which carries them to organs in the body such as the heart pancreas and sex organs The Central Nervous System Brain true core of nervous system takes info from senses processes it makes decisions and sends commands to rest of body Spinal cord long bundles of neurons that carry info to and away from the brain helps control pain response and motor neurons thought o Spinal cord reflexes involve several diff neurons sensory neurons interneurons o Spinal reflexes enable fast often lifesaving actions that don t require conscious Section 4 Methods for Studying the Brain and Overview of the Hindbrain and Limbic System Section 5 Section 6 Section 7