6Modern techniques for studying the brain Lesiondamage to a brain area (electrical or chemical)Ablationremoval of brain areaStereotaxic instrumenta device that allows for precise neurosurgical proceduresSham lesionperforming identical procedures except for damaging the brainproduced by an experimenter in a control subject
7Modern techniques for studying the brain Positron-emission tomography (PET Scan)records emission of radioactivity from injected radioactive chemicals to produce a high- resolution imageshows where activity occurs in the brain
8Modern techniques for studying the brain Recording brain activity involves using a variety of noninvasive methods including:Magnetic Resonance Imaging (MRI)involves the application of a powerful magnetic field to image the braingood for viewing soft tissue
9Modern techniques for studying the brain Electroencephalography (EEG)Records electrical activity produced by cortical regions of the brainProduces a record of brainwaves.Widely used for sleep research
10Structure of the Vertebrate Nervous System Neuroanatomy is the anatomy of the nervous system.Refers to the study of the various parts of the nervous system and their respective function(s).The nervous system consists of many substructures, each comprised of many neurons.
12Structure of the Vertebrate Nervous System The Nervous System is comprised of two major subsystems:The Central Nervous System (CNS)—brain and spinal cordThe Peripheral Nervous System (PNS)
13Central Nervous System BrainComprised of 100 billion neurons“Command Central” of the nervous systemSpinal cordthe part of the CNS found within the spinal columncommunicates with the sense organs and muscles below the level of the headFunctions according to the Bell-Magendie law
14Central Nervous System The Bell-Magendie law states the entering dorsal roots carry sensory information and the exiting ventral roots carry motor information.Figure 4.3: Diagram of a cross-section through the spinal cord.The dorsal root on each side conveys sensory information to the spinal cord; the ventral root conveys motor commands to the muscles.Fig. 4-3, p. 84
15Peripheral Nervous System The Peripheral Nervous System (PNS) sends information to the CNS and is comprised of the:Somatic Nervous SystemAutonomic Nervous System
16Peripheral Nervous System The Somatic Nervous System consists of nerves that:Convey sensory information to the CNS.Transmit messages for motor movement from the CNS to the body.Control skeletal muscles
17Peripheral Nervous System The autonomic nervous system regulates the automatic behaviors of the body (heart rate, blood pressure, respiration, digestion etc).Divides into 2 subsystems:The Sympathetic Nervous SystemThe Parasympathetic Nervous System
18Peripheral Nervous System Sympathetic nervous system: a network of nerves that prepares the organs for rigorous activity by increasing:heart rateblood pressurerespirationetc.Responsible for “fight or flight” response
19Peripheral Nervous System The parasympathetic nervous system facilitates vegetative, nonemergency responses by the organs.decreases functions increased by the sympathetic nervous system.dominant during our relaxed states.
20Anatomical Terms: Views Terms used to describe views when referring to the nervous system include:Ventral: toward the stomachDorsal: toward the backVentral Dorsal
21Anatomical Terms: Views Terms used to describe views when referring to the nervous system include:Anterior: toward the front endPosterior: toward the back endLateral: toward the sideanterior posterior lateral
22Anatomical Terms: Location/direction Terms used to describe location/direction in the nervous system include:Superior: above another partInferior: below another part
23Anatomical Terms: Location/Direction Terms used to describe location/direction in the nervous system include:Lateral: toward the sideMedial: toward the midline
24Anatomical Terms: Location/Direction Terms used to describe location/direction in the nervous system include:Ipsilateral: on same sideContralateral: on opposite side
25Anatomical Terms: Planes/Sections/Cuts Terms referring to planes/sections/cuts:Horizontal: shows brain structures as seen from the topSagittal: shows brain structures as seen from the sideCoronal: shows brain structures as seen from the frontTable 4-1, p. 83
26Anatomical Terms: Specialized Parts Terms referring to specialized parts of the nervous system:Gray matter: cell bodies and dendritesWhite matter: axons, mostly myelinatedTable 4-1, p. 83
27Anatomical Terms: Specialized Parts Terms referring to specialized parts of the nervous system:Tract/projection: set of axons in the CNSNerve: set of axons in the PNSNucleus: cluster of neuron cell bodies within CNSGanglion: cluster of neuron cell bodies in the PNSTable 4-1, p. 83
28Anatomical Terms: Specialized Parts Terms referring to specialized parts of the nervous system:Gyrus (pl: gyri): mound on surface of brainSulcus (pl: sulci): fold/groove separating one gyrus from anotherFissure: long, deep sulcusTable 4-1, p. 83
29Neuroanatomy Handout #3: Brain Structures The brain can be divided into three major divisions:Hindbrain.Midbrain.Forebrain.
30Neuroanatomy Handout #3: Brain Structures The Hindbrain consists of the:MedullaPonsCerebellumLocated at the posterior portion of the brain
31Neuroanatomy Handout #3: Brain Structures The medulla (A):Located just above the spinal cordResponsible for vital reflexes such as breathing, heart rate, vomiting, salivation, coughing and sneezing.Cranial nerves allow the medulla to control sensations from the head, muscle movements in the head, and many parasympathetic outputs to the organs.
33Neuroanatomy Handout #3: Brain Structures Pons (B)lies on each side of the medulla (ventral and anterior).along with the medulla, contains the reticular formation and raphe system, which work together to increase arousal and readiness of other parts of the brain
34Neuroanatomy Handout #3: Brain Structures Cerebellum (C):located posterior to the brainstem with many deep foldshelps regulate motor movement, balance and coordinationalso important for shifting attention between auditory and visual stimuli
35Neuroanatomy Handout #3: Brain Structures The midbrain (D) is comprised of the following structures:Superior colliculus: helps process visual infoInferior colliculus: helps process auditory informationSubstantia nigra – involved in movement
37Neuroanatomy Handout #3: Brain Structures Forebrain: most prominent part of the mammalian brain, consisting of:the outer cortex (“cerebral cortex”)subcortical regions
38Neuroanatomy Handout #3: Brain Structures The limbic system is associated with motivation, emotion, drives and aggression, and includes:Olfactory bulbHypothalamusHippocampusAmygdalaOlfactory bulbs send info about smell to cortex
39Neuroanatomy Handout #3: Brain Structures Hypothalamus (F)Conveys messages to the pituitary gland to trigger the release of hormonesRegulates autonomic nervous systemInvolved in emotions and drives vital to survival:EatingDrinkingSexual behaviorFearFeeling rewarded
40Neuroanatomy Handout #3: Brain Structures Pituitary gland (G)- hormone producing gland found at the base of the hypothalamus.AKA: “Master Gland”
41Neuroanatomy Handout #3: Brain Structures Hippocampus is a large structure of the limbic system critical for storing certain types of memory.H.M., 1953
42Neuroanatomy Handout #3: Brain Structures Amygdala: almond-shaped structure important for:initial emotional response to stimulidirecting motivated behavior at an appropriate target
43Neuroanatomy Handout #3: Brain Structures Forebrain structures include:Thalamus (E) - relay station for the sense organs and main source of input to the cortex.
44Neuroanatomy Handout #3: Brain Structures Basal Ganglia - comprised of the caudate nucleus, the putamen and the globus pallidus.Associated with planning of motor movement, and aspects of memory and emotional expression .
45Neuroanatomy Handout #3: Brain Structures Nucleus basalis:receives input from the hypothalamus and basal gangliakey part of the brain’s system for arousal, wakefulness, and attention
46Neuroanatomy Handout #3: Brain Structures The ventricles are four fluid-filled cavities within the brain containing cerebrospinal fluid. The central canal is a fluid-filled channel in the center of the spinal cord.
47Neuroanatomy Handout #3: Brain Structures Cerebrospinal fluid (CSF) is a clear fluid similar to blood plasma found in the brain and spinal cord:Provides “cushioning” for the brainReservoir of hormones and nutrition for the brain and spinal cordChoroid plexus: groups of cells in the 4 ventricles that continually manufacture CSF
49Neuroanatomy Handout #3: Brain Structures The Cerebral Cortex The cerebral cortex is the most prominent part of the mammalian brain and consists of the cellular layers on the outer surface of the brain.
50Neuroanatomy Handout #3: Brain Structures The Cerebral Cortex The four lobes of the cerebral cortex:Occipital lobeParietal lobeTemporal lobeFrontal lobe2 hemispheres
51Neuroanatomy Handout #3: Brain Structures The Cerebral Cortex The Frontal lobe (H):involved in attention, planning, decision-making, etc.contains Broca’s area (principal speech area) (H1)contains Precentral gyrus (primary motor cortex) (H2), responsible for control of fine motor movement
52Neuroanatomy Handout #3: Brain Structures The Cerebral Cortex Parietal lobe (I) :involved in body sensationscontains postcentral gyrus (I1) (primary sensory area), a main target for touch sensations
53Neuroanatomy Handout #3: Brain Structures The Cerebral Cortex Temporal Lobe (J):involved in hearingalso responsible for some emotional and motivational behaviorscontains primary auditory cortex (J1): Target for auditory information and essential for processing spoken language
54Neuroanatomy Handout #3: Brain Structures The Cerebral Cortex Occipital lobe (K):Highly responsible for visual processingcontains striate cortex or primary visual area (K1)damage can result in cortical blindness
56Neuroanatomy Handout #3: Brain Structures Corpus callosum (O): large bundle of axons joining the 2 hemispheresAnterior commissure (P): small bundle of axons joining the 2 hemispheres
57The Cerebral CortexThe binding problem refers to the question of how the visual, auditory, and other areas of the brain produce a perception of a single object.All areas of the brain communicate with each other