Categories in the BrainVariability in functional websVariability I – Variable IgnitionIgnition of a word web from visual inputSlide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Speaking as a response to ignition of a webSlide 18Slide 19Slide 20Ignition of a web from speech inputSlide 22Slide 23Slide 24Slide 25Visualization from speech inputSlide 27Slide 28Slide 29Cortex-internal ignitionVariability II – Variable web structureSome Key ConceptsUnderstanding semanticsTypes of Conceptual CategoriesPhenomena associated with categoriesPhenomena associated with categories: 1Phenomena associated with categories: 2Fuzzy CategoriesPhenomena associated with categories: 3Prototypicality phenomenaPhenomena associated with categories: 4Phenomena associated with categories: 5Phenomena associated with categories: 6Phenomena associated with categories - 7Beyond description to explanationFacts and hypotheses that we can build onConcepts and percepts: Cortical representationHypotheses concerning functional websHypothesis III(a): AdjacencySlide 50(Part of) the functional web for CATSlide 52How to explain?Phenomena associated with categories: 1-3How do radial categories work?The properties of a category have different weightsNodes have activation thresholdsPrototypical exemplars provide stronger and more rapid activationExplaining PrototypicalityActivation of different sets of properties produces greater or lesser satisfaction of the activation threshold of the cardinal nodeExplaining prototypicality: SummarySlide 62How to explain? Perceptual NeuroscienceConceptual systems and perceptual systemsColumns of different sizesFunctional ColumnsColumns of different sizes In order according to sizeHypercolums: Modules of maxicolumnsPerceptual subcategories and columnar subdivisions of larger columnsFunctional columnsSimilarly..Slide 72Category representations in the cortexHypothesis applied to conceptual categoriesSlide 75Slide 76Slide 77These phenomena (5-7) are interrelatedPertinent neuroanatomical findings: Bidirectional ProcessingBidirectional processing and inferenceSlide 81Category Structure and InferenceExamplesAnother hypothesis of WhorfMechanisms of operationEntrenchment and thinking: a mechanismThinking: Reverberating ActivationExample: Grammatical genderPlausibility of the possibilityChildren learning a language with genderExperiment: Gender and Associations (Boroditsky et al. 2002)Examples:Results of the Experiment (Boroditsky et al. 2002)In conclusion..Slide 95Categories in the BrainLing 411 – 14Variability in functional websI. Variable ignitionII. Variable web structureVariability I – Variable IgnitionWhen ignition of a web occurs, it does not have to include the entire functional webExamples:•It isn’t necessary to speak about everything one sees•Visualization is optional At least to some extentApplication of attention can provide richer detail of ignition•More extensive activation of subwebs•For example, visualizationIgnition of a word web from visual inputVPPAMCArtTIgnition of a word web from visual inputVPPAMCArtTIgnition of a word web from visual inputVPPAMCArtTIgnition of a word web from visual inputVPPAMCArtTIgnition of a word web from visual inputVPPAMCArtTIgnition of a word web from visual inputVPPAMCArtTIgnition of a word web from visual inputVPPAMCArtTIgnition of a word web from visual inputVPPAMCArtTIgnition of a word web from visual inputVPPAMCArtTIgnition of a word web from visual inputVPPAMCArtTIgnition of a word web from visual inputVPPAMCArtTIgnition of a word web from visual inputVPPAMCArtTMention is optionalIgnition of a word web from visual inputVPPAMCArtTSpeaking as a response to ignition of a webVPPAMCArtTSpeaking as a response to ignition of a webVPPAMCArtTSpeaking as a response to ignition of a webVPPAMCArtTThe part of the motor structure that controls the articulation of [dog]Speaking as a response to ignition of a webVPPAMCArtTFrom here to the muscles that control the organs of articulationIgnition of a web from speech inputVPAMCProperties: C – ConceptualM – MemoriesPR – Phonolog. Rec.T – TactileV - VisualTPRIgnition of a web from speech inputVPAMCProperties: C – ConceptualM – MemoriesPR – Phonolog. Rec.T – TactileV - VisualTPRIgnition of a web from speech inputVPRPAMCProperties: C – ConceptualM – MemoriesP – Phonolog. Rec.T – TactileV - VisualTIgnition of a web from speech inputVPAMCProperties: C – ConceptualM – MemoriesPR – Phonol. Rec.T – TactileV - VisualTPRIgnition of a web from speech inputVPAMCTPRUpon hearing “cat” we can also visualize a catProbably a largely optional processVisualization from speech inputVPAMCTPRUpon hearing “cat” we can also visualize a catVPAMCTPRVisualization from speech inputVPAMCTPRVisualization from speech inputVPAMCTPRVisualization from speech inputCortex-internal ignition“… ignition of the web after sufficiently strong stimulation by … cortical neurons outside the functional web. This … cortex-internal activation of a web can be considered the organic basis of being reminded of an object even though it is absent in the environment.” (Pulvermüller 2002: 30)Variability II – Variable web structure Observation: every cat perceived or spoken about is different from others encountered previously•For example, different color•Each web is built based on experienceConsequence: the precise web structure for an individual is likely to differ in details for different instances of the same categoryInertia: some of the differences in a new exemplar are likely to be overlookedSome Key ConceptsFunctional Web(Functional) SubwebCardinal nodeIgnitionReverberationUnderstanding semanticsSemantic structure is largely a matter of conceptual categoriesUnderstanding how categories work is the key to unlock the mysteries of semanticsTo understand how categories work we need to understand how the brain manages categorial informationTypes of Conceptual CategoriesDiscrete•Even integers•Counties in TexasRadial•Birds•VehiclesFamily resemblance•Games•FurnitureIll-defined•Thought•MindPhenomena associated with categories1. No small set of defining features (with rare exceptions) 2. Fuzzy boundaries3. Prototypical members and peripheral members4. Subcategories, and sub-subcategories, in hierarchical chains5. Categories are in the mind, not in the real world6. Categories and