click below
click below
Normal Size Small Size show me how
Lecture 11
Association Cortical Areas. Cognition & Language.
Question | Answer |
---|---|
What are the association cortices? | Regions of the cortex that integrate (associate) information derived from other brain regions. Parietal cortex (attention), Temporal cortex (recognition), frontal cortex (planning and decision making), occipital (concerns cognitive aspects of vision) |
What are the most prominent structures of the human forebrain? | Cerebral hemispheres |
What occupies the outermost portions of the hemisphere? | Cortex |
What does the cortex consist of? | Gyri (folded tissue) and sulci (grooves) |
What is the structural organization of the cortex? | . Archicortex (hippocampus), paleocortex (pyriform cortex), and neocortex (motor and visual cortex) |
What is the structural organization of the neocortex? | 6 laminae, distinct population of cells (pyramidal cell, local axon collateral, stellate cell, dendrites & descending axon), and distinct connectiv |
What is the neocortical circuitry? | Primary source of output, primary output target, columnar connections, laminar connections, and interneurons with layers. |
What is the cytoarchitectonic areas? | Subdivision of cerebral cortex histologically defined based on thickness, cell density, cell size, shape, inputs and outputs |
What is the connectivity of the association cortices? | Receive info. that already had been processed in the sensory thalamic nuclei and primary sensory and motor cortices; receive projections from other cortical areas via cortico-cortical connections: ipsilateral and interhemispheric; receive projections from |
What is contralateral neglect syndrome? | A deficit in perpetual awareness (attention) in which patients have difficulty paying attention to objects and events contralateral to lesion of the parietal lobe (usually right). |
What is hemispheric bias? | Thought to rise from specialization of the left hemisphere for language and right hemisphere for attentive functions. |
. What dominates the control of attention? | The right parietal cortex |
What does right hemisphere lesion cause in parietal cortex? | Severe left neglect |
What does left hemisphere lesion cause in parietal cortex? | Minimal right neglect |
What does partial bilateral lesion cause in parietal cortex? | Severe right neglect |
What is the reward effect? | Selective activation of neurons as a function of attention |
. What contributes to the perception of sensory information in the parietal cortex? | . Inputs from attention-sensitive neurons in the parietal (and prefrontal) cortex to sensory cortices underlies increased responsiveness in neurons of the visual cortex. |
What facilitates perception and appropriate behavior response? | Paying attention to stimulus |
What do lesions to the temporal lobe result in? | Difficulty recognizing, identifying and naming different categories of objects also known as agnosias |
What encodes the recognition of complex stimuli in the temporal association cortex? | Activity of population of neurons rather than by differential activity of individual neurons selective for particular object characteristics. May also be associated with activity of neurons that form columns. These columns are composed of neurons that dif |
What does the frontal cortex integrate and mediate? | Integrates complex information from sensory and motor systems as well as from parietal and temporal association cortices. Mediates planned and appropriate behavior. |
What do lesions to frontal lobe result in? | Diverse and devastating behavioral changes |
What do delay-specific neurons in the frontal cortex do? | Firing of the neurons in the principal sulcus mediates cognitive process necessary to guide behavioral response |
What is cognition? | A function of the association cortices that allows an integrative processing of the information about the stimuli by: attending to , identifying the features, recognizing the objects related, planning the appropriate behavior response, storing the info an |
What is language? | The ability to associate symbols with the specific meanings to express thoughts. |
What brain areas are involved in the comprehension and production of language? | Two regions of the frontal and temporal cortices (Broca's and Wernicke's areas) of the left hemisphere |
What occurs when damage to Broca's and Wernicke's areas? | Compromises essential language functions leaving sensory and motor aspects of communication intact |
What is hemispheric lateralization? | Reflects efficient subdivision of complex functions. Each part of the brain is used with highest efficiency possible. |
What does the observation of split-brain patients confirm and establish? | Established hemispheric lateralization of language |
What is the corpus callosum? | Large bundles of axons that connect the left and right hemispheres |
What is the anterior commisure? | Bundle of axons connecting the temporal lobes |
What methods were utilized to evaluate the language capability of each hemisphere? | Stereognosis and tachistoscopic presentation |
What is and does stereognosis demonstrate? | Objects of different shapes are assessed by one hand (sensory info from right hand is processed by left hemisphere; sensory info from left hand is processed by right hemisphere). Objects held in the right hand are easily named meanwhile those held in left |
What is and does tachistoscopic presentaion demonstrate? | In split-bran patient, info to the left visual field can't reach left hemisphere leading to inability to produce verbal report. Meanwhile, if info presented to the right visual can produce verbal reports. |