Language and Perception

1. Ling 411 – 16 Language and Perception

2. Language and Perception: 3 Topics • The representation of phonological information needed for perception of syllables • Phonological recognition vs phonological perception • Influence of language on non-linguistic perception

3. Language and Perception: Topics • The representation of phonological information needed for perception of syllables • Phonological recognition vs phonological perception • Influence of language on non-linguistic perception

4. Demisyllables [di, de, da, du] F1 and F2 For [de] It is unlikely that [d] is represented as a unit in perception

5. Different sizes in cortical column structure Minicolumn The smallest unit 70-110 neurons Functional column Variable size – depends on experience Intermediate between minicolumn and maxicolumn Maxicolumn (a.k.a. column) 100 to a few hundred minicolumns Hypercolumn Several contiguous maxicolumns

6. Functional columns: a hypothesis The minicolumns within a maxicolumn respond to a common set of features Functional columns are intermediate in size between minicolumns and maxicolumns Different functional columns within a maxicolumn are distinct because of non-shared additional features Shared within the functional column Not shared with the rest of the maxicolumn Mountcastle:“The neurons of a [maxi]column have certain sets of static and dynamic properties in common, upon which others that may differ are superimposed.”

7. Similarly.. • Neurons of a hypercolumn may have similar response features, upon which others that differ may be superimposed • Result is maxicolumns in the hypercolumn sharing certain basic features while differing with respect to others • Such maxicolumns may be further subdivided into functional columns on the basis of additional features • That is, this columnar structure is representing categories and subcategories

8. Hypercolums: Modules of maxicolumns A homotypical area in the temporal lobe of a macaque monkey Category (hypercolumn) Subcategory (can be further subdivided)

9. Perceptual subcategories andcolumnar subdivisions of larger columns • Nodal specificity applies for maxicolumns as well as for minicolumns • The adjacency hypothesis likewise applies to larger categories and columns • Adjacency applies for adjacent maxicolumns • Subcategories of a category have similar function • Therefore their cardinal nodes should be in adjacent locations

10. Functional columns in phonological recognitionA hypothesis Demisyllable (e.g. /de-/) activates a maxicolumn Different functional columns within the maxicolumn for syllables with this demisyllable /ded/, /deb/, /det/, /dek/, /den/, /del/

11. Functional columns in phonological recognitionA hypothesis [de-] deb ded den de- det del dek A maxicolumn (ca. 100 minicolumns) Divided into functional columns (Note that all respond to /de-/)

12. Phonological hypercolumns (a hypothesis) Maybe we have Hypercolumn of contiguous maxicolumns for /e/ With maxicolumns for /de-/, /be-/, etc. Each such maxicolumn subdivided into functional columns for different finals /det/, /ded/, /den/, /deb/, /dem/. /dek/ N.B.: This is a hypothesis, not proven But there is indirect evidence Maybe someday soon we’ll be able to test with sensitive brain imaging

13. Adjacent maxicolumns in phonological cortex? A module of six contiguous maxicolumns de- te- be- pe- Hypercolum Each of these maxicolumns is divided into functional columns ge- ke- Note that the entire module responds to [-e-]

14. Adjacent maxicolumns in phonological cortex? de- te- deb ded den de- det del dek A module of six contiguous maxicolumns be- pe- ge- ke- The entire maxicolumn responds to [de-] The entire module responds to [-e-]

15. REVIEW Functional columns in phonological recognition:A hypothesis • Demisyllable (e.g. /de-/) activates a maxicolumn • Different functional columns within the maxicolumn for syllables with this demisyllable • /ded/, /deb/, /det/, /dek/, /den/, /del/

16. Learning phonological distinctions:A hypothesis de- te- deb ded den de- det del dek 1. In learning, this hypercolumn gets established first, responding to [-e-] be- pe- ge- ke- 3. The maxicolumn gets divided into functional columns 2. It gets subdivided into maxicolumns for demisyllables

17. Remaining problems – lateral inhibition • When a hypercolumn is first recruited, no lateral inhibition among its internal subdivisions • Later, when finer distinctions are learned, they get reinforced by lateral inhibition • Problem: How does this work?

18. Indirect evidence for the hypothesis • Fits the structural organization demonstrated in monkey vision • Cortical structure and function have a high degree of uniformity • MEG is able to pick up different locations in Wernicke’s area for different vowels • MEG can only detect activity of at least 10,000 contiguous apical dendrites (Papanicolaou) • Requires perhaps at least 250 adjacent minicolumns • The size of a maxicolumn or hypercolumn

19. Language and Perception: Topics • The representation of phonological information needed for perception of syllables • Phonological recognition vs phonological perception • Influence of language on non-linguistic perception

20. Perception – Refining a simple-minded view • Not just bottom-up • Top-down processing fills in unsensed details • Not confined to a single perceptual modality • The McGurk effect • Visual input affects auditory perception • Conceptual structure affects auditory perception • Not even confined to posterior cortex • Can also use motor neurons • Experiment: left hand or right hand? • Mirror neurons

21. Perception – Refining a simple-minded view • Not just bottom-up • Top-down processing fills in unsensed details • Not confined to a single perceptual modality • The McGurk effect • Visual input affects auditory perception • Conceptual structure affects auditory perception • Not even confined to posterior cortex • Can also use motor neurons • Experiment: left hand or right hand? • Mirror neurons

22. Top-down processing in perception Node for CUP in conceptual area for drinking vessels Conceptual and perceptual information CUP T MADE OF GLASS SHORT CERAMIC HAS HANDLE Visual properties are in occipital and lower temporal areas Properties

23. Bidirectional processing and inference These connections are bidirectional CUP T MADE OF GLASS SHORT CERAMIC HANDLE

24. Bidirectional processing and inference Thought process: 1. The cardinal concept node is activated by a subset of its property nodes 2. Feed-backward processing activates other property nodes Consequence: We “apprehend” properties that are not actually present in the sensory input CUP T SHORT HANDLE

25. Perception – Refining a simple-minded view • Perception is not just bottom-up • Top-down processing fills in unsensed details • It is not confined to a single perceptual modality • The McGurk effect • Visual input affects auditory perception • Conceptual structure affects auditory perception • It is not even confined to posterior cortex • Can also use motor neurons • Motor activation in speech perception • Mirror neurons

26. The McGurk Effect http://www.youtube.com/watch?v=aFPtc8BVdJk • Acoustic syllable [ba] presented to subjects • with visual presentation of articulatory gestures for [ga] • Subjects typically heard [da] or [ga] • “Evidence has accumulated that visual speech modifies activity in the auditory cortex, even in the primary auditory cortex.” Mikko Sams (2006)

27. Perception depends mainly on cortical structures already present before sensory input “Perception is hallucination constrained by sensory data” Shepherd

28. Perception – Refining a simple-minded view • Not just bottom-up • Top-down processing fills in unsensed details • Not confined to a single perceptual modality • The McGurk effect • Visual input affects auditory perception • Conceptual structure affects auditory perception • Not even confined to posterior cortex • Can also use motor neurons • Experiment: left hand or right hand? • Mirror neurons

29. Left hand or right hand?

30. Left hand or right hand?

31. Left hand or right hand?

32. Left hand or right hand?

33. Left or right hand? • Imaging experiment • Subjects were shown pictures of one hand • Asked to identify: left or right • Functional imaging showed increased CBF in hand area of motor cortex Peter Fox, ca. 2000

34. Motor structures in perception • The left-hand vs. right-hand experiment • ‘Mirror neurons’ in motor cortex • Articulation as aid to phonological perception • Articulation in reading • Motor activity in listening to music • Watching an athletic event

35. Mirror Neurons • NY Times: “One mystery remains: What makes them so smart?” (Jan. 10, 2006) • Answer: They are not smart in themselves • Their apparent smartness is a result of their position: at top of a hierarchy • Compare: • The general of an army • The head of a business • Similarly, high-level conceptual nodes • The “grandmother node”

36. Mirror Neurons • What makes mirror neurons appear to be special? • Ans.: They receive input from visual perception • The superior longitudinal fasciculus • Connects visual perception to motor areas • How can a motor neuron receive perceptual input? • Motor neurons are supposed to operate top-down • Answer: bidirectional processing • They also receive perceptual information • Bottom-up processing

37. Superior Longitudinal Fasciculus From O. D. Creutzfeldt, Cortex Cerebri (1995)

38. Are some neurons “smarter” than others? • Claim: A grandmother node would have to be very smart • Identifies very complex object • Even in many varieties • Alternative: the head of a hierarchy • It is the hierarchy as a whole that has those ‘smarts’ • Similarly, mirror neurons • They get visual input since they are connected to visual areas • Superior longitudinal fasciculus

39. Implications of hierarchical organization • Nodes at a high level in a hierarchy may give the appearance of being very “smart” • This appearance is a consequence of their position — at top of hierarchy • As the top node in a hierarchy, a node has the processing power of the whole hierarchy • Grandmother nodes • Mirror neurons • Compare: • The general of an army • The head of a business organization

40. Multi-Modal Perception • Perception is not just bottom-up • Top-down processing fills in unsensed details • It is not confined to a single perceptual modality • The McGurk effect • Visual input affects auditory perception • Conceptual structure affects auditory perception • It is not even confined to posterior cortex • Can also use motor neurons • Motor activation in speech perception • Mirror neurons

41. A terminological problem • We need to distinguish • Perception narrowly conceived • The basic process of recognition • Single perceptual modality • Bottom-up processing • No motor involvement • Perception broadly conceived • Two different terms needed • Recognition (a.k.a. ‘microperception’) • Bottom-up process in a single perceptual modality • Perception (the broad conception) (a.k.a. ‘macroperception’)

42. Microperception and macroperception • Microperception • A.k.a. recognition • The local process of integrating features • Performed in one perceptual modality • Bottom-up • Macroperception • The overall process of perception • Uses multiple modalities • Uses top-down processing

43. Perceptual structures in motor production • Perceptual structure is used in two ways • Planning (e.g. visualizing while painting) • Monitoring • Examples • Phonological recognition in speech production • Cf. Wernicke’s aphasia • Painting • Musical production • Baseball, soccer, tennis, etc.

44. Language and Perception: Topics • The representation of phonological information needed for perception of syllables • Phonological recognition vs phonological perception • Influence of language on non-linguistic perception

45. Different languages categorize differently • Grammatical gender • Rocks • Plural vs. distributive • Time as metaphorical space • Bells • Time Examples:

46. Grammatical Gender • English: None • French: Masculine, Feminine • German: Masculine, Feminine, Neuter • Oneida: Masculine Feminine-Zoic • Feminine-Inanimate

47. Genders in Oneida (Iroquoian) • Masculine • Feminine-Zoic • Women from puberty to menopause • Animals • Feminine-Inanimate • Little girls • Old women • Inanimate objects

48. Rocks English rock rocks tyhpi tyhtyhpi Monachi

49. Bells – English and French • cloche (of a church) • clochette (on a cow) • sonnette (of a door) • grelot (of a sleigh) • timbre (on a desk) • glas (to announce a death)

50. What time is it? How many times did you go to France? She spends a lot of time in front of the mirror. In the time of the Crusades… At that time, she was sick. Quelle heure est-il? Combien de fois es-tu allé en France? Elle passe beaucoup de temps devant le miroir. A l’epoque des Croidades… A ce moment-là, elle était malade. The Diversity of ‘Time’