Topics for Exam Two 1 Types of neurons a Sensory i b Motor c Interneurons spinal cord 2 Parts of neuron a Cell body Input from sensory organs to the brain and spinal cord i Output from the brain and spinal cord to the muscles and glands i Carry information between other neurons only found in the brain and i Contains the cells nucleus 1 Round centrally located structure 2 Contains DNA b Dendrites Information collectors i ii Receive inputs from neighboring neurons iii iv Inputs may be in thousands If enough inputs the cell s axon may generate an output c Dendritic growth But new dendrites can grow i Mature neurons generally cant divide ii iii provides room for more connections to other neurons iv new connections are basis for learning d Axon i The cell s output structure ii One axon per cell 2 distinct parts 1 Tubelike structure branches at the end that connect to dendrites of e Myelin sheath other cells i White fatty casing on axon ii Acts as an electrical insulator iii Not present on all cells iv When present increases the speed of neural signals down the axon v The loss of myelin is a significant factor in the disease multiple sclerosis MS When myelin is lost the high speed transmission of information is slowed down or blocked completely which could lead the person with the inability to walk write and speak f Neuron to neuron i Axon branch out and end near dendrites of neighboring cells ii Axon terminals are the tips of the axon s branches iii A gap separates the axon terminals from dendrites iv Gap is the synapse g Synapse i Axon terminals contain small storage sacs called synaptic vesicles 3 Parts of neuron 4 Slow and fast messages in neuron 1 Vesicles contain neurotransmitter molecules a Thick and most throughly myelinated axon in the nervous system1 100 of a second for AP to run from CNS to muscle about one meter away thin axons without myelinated sheath conduct at 1 2 meters per second b 5 Studying neurons in rats a Create brain lesions b Stimulate specific areas of the brain by inducing action potentials or stimulate neurons chemically 6 Sympathetic and parasympathetic nervous system a Autonomic involuntary function b Sympathetic i fight or flight response ii iii iv v release adrenaline and noradrenaline increases heart rate and blood pressure increases blood flow to skeletal muscles inhibits digestive functions 1 salvitory glands 2 lungs 3 heart 4 stomach 5 panaceas 6 liver 7 adrenal gland 8 kidney c Parasympathetic i rest and digest system ii calms body to conserve and maintain energy iii lowers heartbeat breathing rate blood pressure 7 Video from class 8 Basic parts of brain and functioning a Brain has 2 hemispheres i Left and right sides are separate ii Corpus callosum major pathway between hemispheres iii Some functions are lateralized 1 Language on left 2 Math music on right iv Lateralization is never 100 v Occipital lobe 1 2 Contains primary visual cortex Input from optic nerve a Most is on surface inside central fissure b Outputs to parietal and temporal lobes vi Temporal lobe 1 Contains primary auditory cortex 2 Inputs are auditory visual patterns a Speech recognition b Face recognition c Word recognition d Memory formation 3 Outputs to limbic system basal ganglia and brainstem Inputs from multiple senses vii Parietal lobe 1 2 Contains primary somatosensory cortex 3 Borders visual and auditory cortex 4 Outputs to frontal lobe a Hand eye coordination b Eye movements c Attention ix Cerebellum action behavior 2 No direct sensory input 3 4 Prefrontal area for working memory Important planning and sequencing areas 1 Coordinated rapid voluntary movements 2 Ex Playing the piano kicking throwing etc 3 Lesion to cerebellum Jerky exaggerated movements a b Difficulty walking c Loss of balance viii Frontal 1 Contains primary motor cortex Its functions are related to motor x Medulla 1 Breathing 2 Heart rate 3 Digestion 4 Other vital reflexes xi Reticular formation a Swallowing coughing vomiting sneezing 1 Network of neurons in the brainstem and thalamus 2 Sleep and arousal 3 Attention xii Thalamus xiii Hypothalamus 1 Relay station in brain 2 Processes most information to and from higher brain centers 1 Contains nuclei involved in a variety of behaviors a Sexual behavior b Hunger thirst c Sleep a Hypothalamus releases hormones or releasing factors which in turn cause d Water and salt balance e Body temperature regulation f Circadian rhythms g Role in hormone secretion 9 Basic parts of brain and damage to them i 10 Basic parts of brain a 11 Split brain patients a 12 Split brain patients 13 Basic parts of brain and functioning 14 Hormones and neurotransmitters pituitary gland o release its hormones b Types of neurotransmitters i Acetylcholine ii Serotonin 1 Found in neuromuscular junction Involved in muscle movements 2 1 2 Involved in sleep Involved in depression anxiety iii Norepinephrine 1 Arousal 2 fight or flight response iv Dopamine a SSRI s works by keeping serotonin in the synapse longer giving it more time to exert an effect involved in movement attention and learning involved in depression 1 2 3 dopamine imbalance also involved in schizophrenia 4 loss of dopamine producing neurons is cause of parkinson s disease v Endorphins 1 Control pain and pleasure 2 Released in response to pain 3 Morphine and codein work on endorphin receptors 4 5 Runners high feeling of pleasure after a long run is due to heavy Involved in healing effects of acupuncture endorphin release vi GABA 1 Main inhibitory neurotransmitter 2 Benzodiazepines and alcohol work on GABA receptor complexes 15 Basic hormones vii glutamate a Chemical messengers secreted into bloodstream b Testosterone c Estrogen d Cortisol e Released by organs including stomach intestines kidneys and brain and endocrine system 16 Parkinson s and Alzheimer s a Parkinsons is the result of abnormalities in the basal ganglia i Loss of dopamine producing neurons in the is cause of parkinsons 1 Difficulty starting and stopping voluntary movements 2 Tremors at rest 3 Stooped posture 4 Rigidity 5 Poor balance ii Treatments 1 L dopa 2 Electrical stimulation of thalamus to stop tremors 3 Adrenal gland transplants b Alzhemiers deterioration of memory reasoning and language skills i Symptoms may be due to loss of ACh neurons 17 Drives and incentives a Drives and incentives complement each other b Weak incentive to eat food in cafeteria but strong drive because you are hungry c Weak drive to eat dessert because you are full but strong