Homework Week 2. PreLab 2 HW #2 Synapses (Page 1 in the HW Section)

Transcription

1 Homework Week 2 Due in Lab PreLab 2 HW #2 Synapses (Page 1 in the HW Section) Reminders No class next Monday Quiz 1 5:30pm on Tuesday, 1/22/13 Study guide posted under Study Aids section of website

2 Thought Questions 1. When you have one of your mandibular teeth worked on at the dentist and he gives you a shot to deaden half of your mouth, what division of the nervous system is being affected by the lidocaine? 2. What do you think it s mode of action is? Hint: Remember Physio-EX in lab? 3. Is it affecting a cranial or spinal nerve?

3 Thought Questions 1. What 3 structures maintain resting membrane potential in neurons? 2. What membrane structure is responsible for depolarization during an action potential? 3. What membrane structure is responsible for repolarization during an action potential?

4 The Nervous System T H E C E N T R A L N E R V O U S S Y S T E M T H E B R A I N

5 Introduction Integration Memory Learning Sensation and perception

6 Organization of Neural Tissue White matter versus gray matter Fiber bundles Nerves versus tracts Nerve cell bodies Nucleus versus ganglion

7 Organization of Neural Tissue Generally Central cavity surrounded by a gray matter core External white matter Composed of myelinated fiber tracts Brain has additional areas of gray matter Not present in spinal cord

8 Central cavity Migratory pattern of neurons Cerebrum Cerebellum Cortex of gray matter Inner gray matter Outer white matter Gray matter Region of cerebellum Central cavity Inner gray matter Outer white matter Brain stem Spinal cord Gray matter Central cavity Outer white matter Inner gray matter Copyright 2010 Pearson Education, Inc. Figure 12.4

9 Organization of Neural Tissue Similar pattern with additional areas of gray matter

10 The Brain Functions Conscious perception Internal regulation Average adult male 3.5 lbs Average adult female 3.2 lbs Same brain mass to body mass ratio!

11 The Brain 4 Adult brain regions 1. Cerebral hemispheres (cerebrum) 2. Diencephalon 3. Cerebellum 4. Brain stem (midbrain, pons, and medulla)

12 The Brain

13 The Brain Four major regions are connected by ventricles and aqueducts

14 The Brain Ventricles Filled with cerebrospinal fluid Lined by ependymal cells Continuous with one another

15 The Cerebrum Cerebral hemispheres form superior part of brain About 80% of brain mass 3 tissue layers Superficial cortex = gray matter Internal white matter Basal nuclei = islands of gray matter

16 Anterior Longitudinal fissure Frontal lobe Cerebral veins and arteries covered by arachnoid mater Left cerebral hemisphere (c) Posterior Parietal lobe Right cerebral hemisphere Occipital lobe Figure 12.6c

17 The Cerebrum Cerebral cortex Surface layer of cerebrum Executive Suite Convolutions Gyri elevated ridges Sulci shallow grooves Fissures deep grooves, separate larger regions of the brain

18 The Cerebrum Fissures divide cerebral hemispheres into 4 lobes

19 The Cerebrum 3 types of functional areas in the cerebral cortex 1. Motor areas Control voluntary movement 2. Sensory areas Conscious awareness of sensation 3. Association areas Integrate diverse information

20 The Cerebrum Functional areas of the cerebral cortex Contralateral orientation Hemispheres are functionally specialized Conscious behavior involves the entire cortex

21 Cerebral Motor Activity Motor areas Primary motor cortex Premotor cortex Frontal eye field Broca s area (outlined by dashes) Prefrontal cortex Working memory for spatial tasks Executive area for task management Working memory for object-recall tasks Solving complex, multitask problems (a) Lateral view, left cerebral hemisphere Central sulcus Sensory areas and related association areas Primary somatosensory cortex Somatosensory association cortex Gustatory cortex (in insula) Wernicke s area (outlined by dashes) Primary visual cortex Visual association area Auditory association area Primary auditory cortex Somatic sensation Taste Vision Hearing Primary motor cortex Motor association cortex Primary sensory cortex Sensory association cortex Multimodal association cortex Figure 12.8a

22 Cerebral Motor Activity Primary motor cortex Large pyramidal cells of the precentral gyrus Long axons pyramidal (corticospinal) tracts Allows conscious control Precise, skilled, voluntary movements

23 Motor Homunculus Somatotopy of precentral gyrus (primary motor cortex) Motor map in precentral gyrus Motor Posterior Anterior Jaw Toes Motor homunculi: upside-down caricatures representing the motor innervation of body regions Tongue Swallowing Primary motor cortex (precentral gyrus) Figure 12.9

24 Cerebral Motor Activity Premotor cortex Anterior to the precentral gyrus Controls learned, repetitious or patterned motor skills Coordinates simultaneous or sequential actions Involved in the planning of movements that depend on sensory feedback

25 Cerebral Motor Activity Broca s area Anterior to the inferior region of the premotor area Present in one hemisphere (usually the left) Motor speech area that directs muscles of the tongue Active as one prepares to speak

26 Cerebral Motor Activity Frontal eye field Anterior to the premotor cortex and superior to Broca s area Controls voluntary eye movements

27 Cerebral Motor Activity Motor areas Primary motor cortex Premotor cortex Frontal eye field Broca s area (outlined by dashes) Prefrontal cortex Working memory for spatial tasks Executive area for task management Working memory for object-recall tasks Solving complex, multitask problems (a) Lateral view, left cerebral hemisphere Central sulcus Sensory areas and related association areas Primary somatosensory cortex Somatosensory association cortex Gustatory cortex (in insula) Wernicke s area (outlined by dashes) Primary visual cortex Visual association area Auditory association area Primary auditory cortex Somatic sensation Taste Vision Hearing Primary motor cortex Motor association cortex Primary sensory cortex Sensory association cortex Multimodal association cortex Figure 12.8a

28 Cerebral Vascular Accident (Stroke) Types Ischemic stroke Hemorrhagic stroke Result Tissue death called an infarct Effects are determined by Where it occurs How large the area involved

29 Stroke

30 Stroke

31 Motor areas Primary motor cortex Premotor cortex Frontal eye field Broca s area (outlined by dashes) Prefrontal cortex Working memory for spatial tasks Executive area for task management Working memory for object-recall tasks Solving complex, multitask problems (a) Lateral view, left cerebral hemisphere Cerebral Sensory Activity Central sulcus Primary motor cortex Motor association cortex Primary sensory cortex Sensory association cortex Multimodal association cortex Sensory areas & related association areas Primary somatosensory cortex Somatosensory association cortex Gustatory cortex (in insula) Wernicke s area (outlined by dashes) Primary visual cortex Visual association area Auditory association area Primary auditory cortex Somatic sensation Taste Vision Hearing Figure 12.8a

32 Cerebral Sensory Activity Widely dispersed Parietal, temporal & occipital lobes Concerned with conscious awareness of sensation

33 Cerebral Sensory Activity Primary somatosensory cortex In the postcentral gyri, parietal lobe Stimuli from skin, skeletal muscles, and joints Capable of spatial discrimination Identification of body region being stimulated

34 Posterior Anterior Sensory Sensory map in postcentral gyrus Genitals Primary somatosensory cortex (postcentral gyrus) Intraabdominal Copyright 2010 Pearson Education, Inc. Figure 12.9

35 Cerebral Sensory Activity Somatosensory association cortex Posterior to the primary somatosensory cortex Integrates sensory input from primary somatosensory cortex Integrates and analyzes inputs Temperature, size, texture Relationship of parts of objects being felt Example: keys in pocket

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37 Cerebral Sensory Activity Visual areas Primary visual cortex Occipital lobe Receives visual information from the retinas Visual association area Surrounds the primary visual cortex Uses past visual experiences to interpret visual stimuli Example: color, form and movement Complex processing involves entire posterior half of the hemispheres

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39 Cerebral Sensory Activity Auditory areas Primary auditory cortex Temporal lobes Interprets information from inner ear Pitch, loudness and location Auditory association area Posterior to the primary auditory cortex Stores memories of sounds and permits perception of sounds

40 Cerebral Sensory Activity Motor areas Primary motor cortex Premotor cortex Frontal eye field Broca s area (outlined by dashes) Prefrontal cortex Working memory for spatial tasks Executive area for task management Working memory for object-recall tasks Solving complex, multitask problems (a) Lateral view, left cerebral hemisphere Central sulcus Sensory areas and related association areas Primary somatosensory cortex Somatosensory association cortex Gustatory cortex (in insula) Wernicke s area (outlined by dashes) Primary visual cortex Visual association area Auditory association area Primary auditory cortex Somatic sensation Taste Vision Hearing Primary motor cortex Motor association cortex Primary sensory cortex Sensory association cortex Multimodal association cortex Figure 12.8a

41 Association Areas Receive inputs from multiple sensory areas Send outputs to multiple areas Including the premotor cortex Function Allows us to give meaning to information received, store it as memory, compare it to previous experience, and decide on action to take Multimodal association areas

42 Association Activity Three areas Prefrontal cortex Posterior association area (not discussed here) Limbic association area

43 Cerebral Association Activity Motor areas Primary motor cortex Premotor cortex Frontal eye field Broca s area (outlined by dashes) Prefrontal cortex Working memory for spatial tasks Executive area for task management Working memory for object-recall tasks Solving complex, multitask problems (a) Lateral view, left cerebral hemisphere Central sulcus Sensory areas and related association areas Primary somatosensory cortex Somatosensory association cortex Gustatory cortex (in insula) Wernicke s area (outlined by dashes) Primary visual cortex Visual association area Auditory association area Primary auditory cortex Somatic sensation Taste Vision Hearing Primary motor cortex Motor association cortex Primary sensory cortex Sensory association cortex Multimodal association cortex Figure 12.8a

44 Association Activity Prefrontal cortex Most complicated cortical region Involved with intellect, cognition, recall and personality Contains working memory needed for judgment, reasoning and conscience Development depends on feedback from social environment

45 Association Activity Limbic association area Part of the limbic system Provides emotional impact that helps establish memories Connections with prefrontal cortex regulate emotional expression

46 Cerebral Association Activity Motor areas Primary motor cortex Premotor cortex Frontal eye field Broca s area (outlined by dashes) Prefrontal cortex Working memory for spatial tasks Executive area for task management Working memory for object-recall tasks Solving complex, multitask problems (a) Lateral view, left cerebral hemisphere Central sulcus Sensory areas and related association areas Primary somatosensory cortex Somatosensory association cortex Gustatory cortex (in insula) Wernicke s area (outlined by dashes) Primary visual cortex Visual association area Auditory association area Primary auditory cortex Somatic sensation Taste Vision Hearing Primary motor cortex Motor association cortex Primary sensory cortex Sensory association cortex Multimodal association cortex Figure 12.8a

47 Cerebral Lateralization Left hemisphere Math Logic Language Controls right side of body Right hemisphere Visual-spatial skills Intuition Emotion Art and music Controls left side of body

48 Cerebral White Matter Projection tracts Connect cerebrum w/other body locations Association tracts Interconnect cerebral cortex (same side) Commissural tracts Connect two hemispheres

49 White Matter Tracts

50 Cerebral Gray Matter Basal Nuclei Association of gray matter deep in cerebral hemispheres Contribute to muscle coordination by excitatory innervation Ex. Parkinson s

51 Basal Nuclei

52 Complete CNS 23 #5, 1-6 CNS 21 Crossword puzzle Activity 52