11Nervous SystemSystem of nerves involved in thought processes, heartbeat, visual-motor coordination, etc…Central and Peripheral systems
12Central Nervous System Consists of the brain and spinal cord
13Spinal CordA column of nerves within the spine that transmits messages from sensory receptors to the brain and from the brain to muscles and glands throughout the body.
14Spinal CordSpinal Reflexes: an unlearned response to a stimulus that may involve only two neuronsa) Sensory (afferent) neuron-to cortexb) Motor (efferent) neuron-awayS A M EYou are *affected* by a situation, you *effect* change on someone else.Blink, swallow,knee-jerk, sexual responses, urinating, etc…
15Brain Hindbrain(lower part of brain): Medulla-heart rate, blood pressure, respirationPons-respiration, attention, sleep, dreamingCerebellum-muscle coordination and balance
16Brain Vital in the functions of attention, sleep, and arousal Reticular Activating System (RAS):Vital in the functions of attention, sleep, and arousalInjury to RAS can cause comatoseFiltering (awakened by infant)
17Brain Forebrain (front most part): 1). Thalamus-center of brain Relay station for sensory stimulationRelays sensory input from the eyes to the visual areas of the cerebral cortexFunctions of sleep and attention
18Brain Forebrain (front most part): 2). Hypothalamus-beneath thalamus and above pituitary glandBody temperature, motivation, emotionInvolved in hunger, thirst, sexual behavior, caring for offspring, aggression
19Brain Forebrain (front most part): 3). Limbic system-inner edge of cerebrum and in mammals onlyMemory, emotion, drives of hunger, sex, aggressionAmygdala-facilitates aggressive responses
20Brain Forebrain (front most part): 4). Basil ganglia-between thalamus and cerebrumControl of movements and coordinationDopamine produced-degeneration can cause Parkinson’s disease
21Brain Forebrain (front most part): 5). Cerebrum-crowning glory of brainCerebral cortex-the wrinkled and convoluted surfaceConsists of two hemispheresCorpus Callosum-connects the two hemispheres
22Peripheral Nervous System Consists of sensory and motor neurons that transmit messages to and from the central nervous systemWithout the PNS, our brains would be isolated from the worldSomatic and Autonomic NS
23Somatic Nervous System Connects the central nervous system with sensory receptors, skeletal muscles, and the surface of the bodyEx:raising hand, winking, running, posture, balance
24Autonomic Nervous System Regulates the glands and the muscles of internal organsHeartbeat, respiration, digestion, dilation of the pupils of the eyesCan occur automaticallySympathetic & Parasympathetic
25Autonomic Nervous System Sympathetic- most active during processes that involve the spending of body energy from stored reserves“Fight-or-Flight”
26Autonomic Nervous System Parasympathetic- most active during processes that replenish reserves of energy (eating)
27Autonomic Nervous System Sympathetic--accelerates the heart rate-inhibits digestionParasympathetic--decelerates the heart rate-stimulates digestive processes
44The BrainTechniques to Study the BrainA brain lesion experimentally destroys brain tissue to study animal behaviors after such destruction.OBJECTIVE 11| Describe several techniques for studying the brain.Hubel (1990)
45Clinical ObservationClinical observations have shed light on a number of brain disorders. Alterations in brain morphology due to neurological and psychiatric diseases are now being catalogued.Tom Landers/ Boston Globe
46Electroencephalogram (EEG) An amplified recording of the electrical waves sweeping across the brain’s surface, measured by electrodes placed on the scalp.
47PET ScanPET (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
48MRI ScanMRI (magnetic resonance imaging) uses magnetic fields and radio waves to produce computer-generated images that distinguish among different types of brain tissue. Top images show ventricular enlargement in a schizophrenic patient. Bottom image shows brain regions when a participants lies.Both photos from Daniel Weinberger, M.D., CBDB, NIMHJames Salzano/ Salzano PhotoLucy Reading/ Lucy Illustrations
49Older Brain Structures The Brainstem is the oldest part of the brain, beginning where the spinal cord swells and enters the skull. It is responsible for automatic survival functions.OBJECTIVE 12| Describe the components of the brainstem and summarize the functions of the brainstem, thalamus and cerebellum.
50Brain StemThe Medulla [muh-DUL-uh] is the base of the brainstem that controls heartbeat and breathing.Reticular Formation is a nerve network in the brainstem that plays an important role in controlling arousal.
51Brain StemThe Thalamus [THAL-uh-muss] is the brain’s sensory switchboard, located on top of the brainstem. It directs messages to the sensory areas in the cortex and transmits replies to the cerebellum and medulla.
52CerebellumThe “little brain” attached to the rear of the brainstem. It helps coordinate voluntary movements and balance.
53The Limbic SystemThe Limbic System is a doughnut-shaped system of neural structures at the border of the brainstem and cerebrum, associated with emotions such as fear, aggression and drives for food and sex. It includes the hippocampus, amygdala, and hypothalamus.OBJECTIVE 13| Describe the structures and functions of the limbic system, and explain how one of these structures controls the pituitary gland.
54AmygdalaThe Amygdala [ah-MIG-dah-la] consists of two almond-shaped neural clusters linked to the emotions of fear and anger.
55HypothalamusThe Hypothalamus lies below (hypo) the thalamus. It directs several maintenance activities like eating, drinking, body temperature, and control of emotions. It helps govern the endocrine system via the pituitary gland.
56Reward CenterRats cross an electrified grid for self-stimulation when electrodes are placed in the reward (hypothalamus) center (top picture). When the limbic system is manipulated, a rat will navigate fields or climb up a tree (bottom picture).Sanjiv Talwar, SUNY Downstate
57The Cerebral CortexThe intricate fabric of interconnected neural cells that covers the cerebral hemispheres. It is the body’s ultimate control and information processing center.OBJECTIVE 14| Define cerebral cortex and explain its importance fro the human brain.
58Structure of the Cortex Each brain hemisphere is divided into four lobes that are separated by prominent fissures. These lobes are the frontal lobe (forehead), parietal lobe (top to rear head), occipital lobe (back head) and temporal lobe (side of head).OBJECTIVE 15| Identify the four lobes of the cerebral cortex.
60Functions of the Cortex The Motor Cortex is the area at the rear of the frontal lobes that control voluntary movements. The Sensory Cortex (parietal cortex) receives information from skin surface and sense organs.OBJECTIVE 16| Summarize some of the findings on the functions of the motor cortex and the sensory cortex, and discuss the importance of the association areas.
61Visual FunctionThe functional MRI scan shows the visual cortex is active as the subject looks at faces.Courtesy of V.P. Clark, K. Keill, J. Ma. Maisog, S. Courtney, L.G.Ungerleider, and J.V. Haxby,National Institute of Mental Health
62Auditory FunctionThe functional MRI scan shows the auditory cortex is active in patients who hallucinate.
63Association AreasMore intelligent animals have increased “uncommitted” or association areas of the cortex.
64LanguageAphasia 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).OBJECTIVE 17| Describe the five brain areas that would be involved if you read this sentence aloud.
68The Brain’s Plasticity The brain is sculpted by our genes but also by our experiences.Plasticity refers to the brain’s ability to modify itself after some type of injury or illness.OBJECTIVE 18| Discuss brain’s plasticity following injury or illness.
69Our brain is divided into two hemispheres. Our Divided BrainOur brain is divided into two hemispheres.The left hemisphere processes reading, writing, speaking, mathematics, and comprehension skills. In the 1960s, it was termed as the dominant brain.OBJECTIVE 19| Describe split-brain research, and explain how it helps us to understand the functions of our left and right hemispheres.
70Splitting the BrainA procedure in which the two hemispheres of the brain are isolated by cutting the connecting fibers (mainly those of the corpus callosum) between them.Corpus CallosumCourtesy of Terence Williams, University of IowaMartin M. Rother
71Split Brain PatientsWith the corpus callosum severed, objects (apple) presented in the right visual field can be named. Objects (pencil) in the left visual field cannot.
75Non-Split BrainsPeople with intact brains also show left-right hemispheric differences in mental abilities.A number of brain scan studies show normal individuals engage their right brain when completing a perceptual task and their left brain when carrying out a linguistic task.
76Brain Organization & Handedness Is handedness inherited? Yes. Archival and historic studies, as well as modern medical studies, show that the right hand is preferred. This suggests genes and/or prenatal factors influence handedness.OBJECTIVE 20| Discuss the relationship among brain organization, handedness, and mortality.
77Is it Alright to be Left Handed? Being left handed is difficult in a right-handed world.
78Is it Alright to be Left Handed? The percentage of left-handed individuals decreases sharply in samples of older people (Coren, 1993).
80Aphasia Damage to the left part of the brain in the cerebral cortex Definition:impaired ability to comprehend or express oneself through language
81Broca’s Area Prevents a person from producing speech Person can understand languageWords are not properly formedSpeech is slow and slurred
82Wernicke’s Area Loss of ability to understand language Person can speak clearly, but the words that are put together make no sense.“Word salad” because it appears that the words are all mixed up like the vegetables in a salad
86Alzheimer’s DiseaseA progressive form of mental deterioration that may affect as many as 4 million AmericansConnected with aging but it is a disease and NOT part of a normal aging process
87Alzheimer’s DiseaseCharacterized by progressive deterioration in mental processes such as memory, language, and problem solvingSeriously impairs vocational and social functioning
88Alzheimer’s Disease Memory loss: difficult to recall basic info (zip codes, telephone #s, names of grandchildren, addresses)Large gaps in memory for recent eventsMay fail to recognize familiar people or forget their names
89Alzheimer’s Disease Continue.. May not recognize themselves in the mirrorUnable to recall names of their school, birthplace, parentsNo longer able to speak in full sentences and limit their verbal responses to a few words
90Alzheimer’s DiseaseSubtle personality changes: signs of withdrawal or irritabilityMay need assistance to manage everyday tasks (selecting clothes to wear)Difficulties in personal functioning (using bathroom and washing themselves)
91Alzheimer’s DiseaseMay pace or fidget or display aggressive behavior (yelling, hitting, throwing)May wander off and not be able to find their way back1 in 3 show signs of hallucinations or delusions
92Alzheimer’s Disease Severe cases: People become helpless-unable to communicate or walk and require help in toileting and feeding.
93Alzheimer’s Disease Discovered by German physician Alois Alzheimer Found brain abnormalities in a 56-year old woman with dementia
94Brain Abnormalities1) Plaques: destroy brain tissues which leads to loss of memory function, confusion, and other symptoms2) Tangles: twisted bundles of nerve cells
95BiochemicalReduced levels of acetylcholine (ACh): reflect loss of brain cells and can lead to brain trauma, aluminum poisoningReduced metabolic ratesNegative correlation between cognitive performance and metabolic rate
96Genetic Transmission90% of people who inherit a key gene from both parents contract Alzheimer’s disease by the age of 75Chemotherapy is used to heighten ACh levelsResearchers are hopeful that genetic studies may lead to effective medications