Cortex & Connections Chapter 26 PDF

Cortex & Connections Chapter 26 Objectives Explain the movement of cortical information from primary sensory cortex to primary motor cortex List the location and functions of the cortical association areas Explain the specific cortical functions of communication, memory, and spatia...

Cortex & Connections Chapter 26 Objectives Explain the movement of cortical information from primary sensory cortex to primary motor cortex List the location and functions of the cortical association areas Explain the specific cortical functions of communication, memory, and spatial perception Relate clinical symptoms of damage to specific cortical areas (ie, frontal lobe, primary motor cortex, occipital lobe, etc) Cerebral cortex  doing andskinis whatm iscles Primary somatosensory cortex Receives information from tactile and proprioceptive receptors via a three-neuron pathway Peripheral afferent/dorsal column neuron Medial lemniscus neuron Thalamocortical neuron Primary somatosensory cortex Discriminative touch and proprioception Awareness through somatosensation Determine location of stimulus Understanding of shape, size, and texture of a structure Primary cortices Primary auditory cortices (PAC) Receive information from the cochlea of both ears via a pathway that synapses in the inferior colliculus and medial geniculate body before reaching the cortex Primary cortices a.sn Primary vestibular cortices (PVC) Receive information regarding head movement and head position, relative to gravity by a vestibulothalamocortical pathway. Primary cortices Primary visual cortex Visual information travels to the cortex via a pathway from the retina to the lateral geniculate body of the thalamus, then to the primary visual cortex. Cerebral cortex Association areas Dorsolateral prefrontal Parietotemporal Ventral and medial dorsal prefrontal Association areas Personality Interpretation of sensation Processing of memory Emotions Intelligence Dorsolateral prefrontal cortex Functions include self-awareness and executive functions. decisionsabouty ourself Executive functions include: making Deciding on a goal Planning how to accomplish the goal Executing a plan Monitoring the execution of the plan Parietotemporal association cortex Cognitive intelligence Problem-solving Comprehension of communication Understanding of spatial relationships Ventral and medial dorsal prefrontal association cortex Impulse control Personality Reactions to surroundings Association areas Results of Lesions of Cortex Working memory Maintains goal-relevant information for a short time. Is essential for language, problem-solving, mental navigation, and reasoning. Complex mental multitasking requires working memory and is central to cognition. Prefrontal cortex and the parietotemporal association cortex maintain, manipulate, and update information in working memory.  Communication Wernicke’s area 3 i iIEE Comprehension of the spoken language EEE.EE Interprets symbols Broca’s area put speechout Provides instructions for language output Planning the movements to produce speech O O Correlates words when writing  Terms to Know Apraxia – loss of task performance without loss of movement, i.e. agraphia notthe Etat It Agnosia – loss of the sense touch in that the significance is lost, i.e. nearingmusic astereognosia, visual agnosia, auditory agnosia, amusia losetown smell Receptive (Wernicke’s) aphasia – cannot really understand spoken language (but may be able to hear) and all other language is impacted. These patients make up word, substitute the wrong words and use disordered syntax – all without insight into their problem Expressive aphasia (Broca) – hallmark is the ability to understand written and verbal but unable to generate appropriate words, patient is aware of the nonsense articulations lose of speech  Spatial perception Body Mental representation of how the body is anatomically arranged Body in relation to its surroundings Enables individuals to locate objects in space and to navigate accurately External world Ability to plan a route from one site to another Visual perceptual deficits  Symptoms of Right Parietal Lobe Lesions Hemineglect syndrome Ignores anything to the left (visual field) Happens almost exclusively on after right lesions Loss of recognition of spacial relations Loss of prosody (see below)