1. More on the Functional Neuroanatomy of Language Ling 411 – 20

2. Schedule of Presentations Delclos Planum Temp Banneyer Categories Ruby Tso Writing Bosley Synesthesia McClure Gram.-Broca Ezzell Lg Dev. (Kuhl) Rasmussen 2 nd language Brown Lg&Thought Gilcrease-Garcia AG Koby Music Tsai Tones Mauvais LH-RH anat. Shelton Thalamus Delgado Amusia Tu Apr 13 Th Apr 15 Tu Apr 20 Th Apr 22

3. Hickok’s proposal on conduction aphasia  At least one type of conduction aphasia results from damage to phonological processing systems in auditory cortex which participate both in speech perception and in speech production i.e., Wernicke’s area  The asymmetry between production (impaired) and comprehension (spared) can be explained in terms of different degrees of lateralization in the … systems that support (or can support) these functions (2000: 89)

4. Why isn’t this Wernicke’s aphasia?  The area identified by Hickok for conduction aphasia is Wernicke’s area Hickok claims that such damage is responsible for conduction aphasia  Conduction aphasia and Wernicke’s aphasia In conduction aphasia  Comprehension is relatively ok Hickok claims the RH pSTP also participates in speech recognition  Patient is aware of errors in repetition Hickok proposes that in Wernicke’s aphasia the damage extends beyond Wernicke’s area  MTG (p. 101), (maybe also AG?)

5. Hickok & Poeppel (2000)  Left temporal-parietal-occipital junction area is “typically involved to some extent in Wernicke’s aphasia, which … has a prominent post-phonemic component to the deficit profile. (Toward a functional neuroanatomy of speech perception, p. 7)

6. MR template – Wernicke Aphasia (patient I) Poster -ior portio n of super- ior and middle temp- oral gyri

7. MR template – Wernicke Aphasia (patient II) Super- ior temp- oral gyrus, AG, SMG

8. Hickok’s proposal on speech perception  The primary substrate for speech perception is the posterior temporal plane (pSTP) pSTP – Heschl’s gyrus plus planum temporale  Conduction aphasia can result from damage to exactly this area in left hemisphere  Apparent paradox: Comprehension is preserved in conduction aphasia  Explanation: Speech perception is subserved by pSTP in both hemispheres (2000: 90)

9. RH involvement in speech perception Isolated RH  Evidence from tests of isolated RH Split-brain studies Wada test  Sodium amytol, sodium barbitol Discrimination of speech sounds Comprehension of syntactically simple speech (Hickok 2000: 92)

10. Benson and Ardila on conduction aphasia “… a single type of aphasia may have distinctly different loci of pathology. Both conduction aphasia and transcortical motor aphasia are examples of this inconsistency.” (117) (See also p. 135)

11. Hannah Damasio on conduction aphasia “Conduction aphasia is associated with left perisylvian lesions involving the primary auditory cortex…, a portion of the surrounding association cortex…, and to a variable degree the insula and its subcortical white matter as well as the supramarginal gyrus (area 40). Not all of these regions need to be damaged in order to produce this type of aphasia. In some cases without involvement of auditory and insular regions, the compromise of area 40 is extensive…. In others, the supramarginal gyrus may be completely spared and the damage limited to insula and auditory cortices … or even to the insula alone….” (1998: 47)

12. CT template – Conduction Aphasia (patient I)

13. CT template – Conduction Aphasia (patient II) Left auditory cortex and insula

14. Kurt Goldstein on Conduction Aphasia  Kurt Goldstein (1878-1965) German Studied with Wernicke Influenced by Gestalt psychology (Koffka 1935)  Adopted a “holistic” approach Became the best-known spokesman for this approach Important publication in 1948  Criticized the Wernicke-Lichtheim view of conduction aphasia Not the arcuate fasciculus but a central area Proposed the term ‘Central Aphasia’  Now we see that there are really three kinds of conduction aphasia

15. 3 or 4 types of conduction aphasia  Damage to arcuate fasciculus The classical one  Proposed by Wernicke and Lichtheim  Doubted by Hickok But Hickok is wrong!  Damage to SMG Proposed by Goldstein Supported by Hickok  Damage to Wernicke’s area (but not to AG) New proposal of Hickok  Possible 4 th type: Damage to insula

16. Repetition in Wernicke’s aphasia Model for Repetition  black  shoe  He parks the car  It goes between two others Patient’s Response  blackboard  shoelace  He park … he came with the car. He came with his car.  It went two cars … between the cars

17. Goodglass on conduction aphasia Unlike the patient with Wernicke’s aphasia, patients with conduction aphasia are usually acutely aware of the inaccuracy of their production and make repeated attempts at self-correction. As they do so, they may correct one portion of the target while introducing a new error elsewhere, sometimes wandering further afield and sometimes approaching closer to or even succeeding in saying the desired word. (1993: 142)

18. Picture naming in conduction aphasia  Picture of..  whistle  pretzel  Patient’s Response  tris.. chi.. trissle.. sissle.. twiss.. ciss.  trep.. tretzle.. trethle.. tredfl… ki

19. Lamb’s email query to Hickok (April 1, 2010) Hi Greg - In my neurolinguistics class we have just been considering your 2000 paper from the Grodzinsky et al. volume, with its new perspective on, among other things, these two types of aphasia. Very intriguing, but I have a question: How do you explain this: When you give a conduction aphasic words to repeat, he/she commonly produces a phonemic paraphasia and then keeps trying, since he/she recognizes the error; but a Wernicke's aphasic usually stops after one incorrect repetition, evidently unaware of the error. Acc. to your proposal, both types of aphasic have LH phonological recognition wiped out, and both have intact RH pSTG.

20. Hickok’s response (April 1, 2010) Hi Syd, Good to hear from you. That is an interesting question. I think there are two possibilities. One is that the conduction aphasics don't have as much damage to the left hemisphere phonological systems we (I) might have thought. I.e., the damage is more often involving the posterior Sylvian region (Spt). The intact left and right hemi phonological systems allow the patient to clearly recognize their errors and self correct. Wernicke's on the other hand typically have extensive damage to the left hemi phonological systems which, because of their role in production, may have a larger role in self monitoring. Another possibility, perhaps in conjunction with the first, is that wernicke's have damage to semantic (access) systems as well. it may be much harder to notice a phonological error if you can't tell whether it is a word or not.

21. The Connection between Phonological Recognition and Phonological Production Hickok (2000) proposes a revision of the standard hypothesis The revision is like that previously proposed by Goldstein Now, evidence from DTI (cf. Friederici)

22. The Perception-Production Interface  We have phonological recognition in Wernicke’s area And in RH homolog of Wernicke’s area  And phonological production in Broca’s area And in RH homolog of Broca’s area  Clearly, they have to be connected  The traditional view Direct connection: the arcuate fasciculus Proposed by Wernicke, supported by Geschwind  Alternative view Supramarginal gyrus (SMG) as intermediary Proposed by Hickok  with support from Damasio and Goldstein REVIEW

23. The Intermediate System Hypothesis Speech Production Speech Recognition Supramarginal Gyrus Auditory-Motor Interface

24. Arguments for Direct Connection Hypothesis  No additional intervening structure needed  We have anatomical evidence for the arcuate fasciculus arcuate fasciculus And for its connections from Wernicke’s area to Broca’s area

25. Arguments for SMG Interface Hypothesis  Damasio cites SMG damage as a major cause of conduction aphasia Consistent with earlier findings of Goldstein  “Central aphasia” (Goldstein 1948)  Connectivity studies in non-human primates fail to find direct connection between auditory cortex and ventral posterior frontal lobe But support the claim that the lower parietal lobe provides an interface between these areas (Hickok 2000: 99)  SMG is a likely site of higher-level proprioceptive processing of speech

26. Arguments for SMG Interface Hypothesis  Damasio cites SMG damage as a major cause of conduction aphasia Consistent with earlier findings of Goldstein  “Central aphasia” (Goldstein 1948)  Anatomical studies in macaque monkeys fail to find direct connection (between corresponding areas) (Hickok 2000: 99)  SMG is a likely site of higher-level proprioceptive processing of speech (next slide)

27. Motor and Somatosensory Areas for speech Mouth Hand Fingers Arm Trunk Leg Central Sulcus 12 3 4 1 – Phonological production 2 – Articulation 3 – Articulatory monitoring 4 – Phonological monitoring Post-Central Sulcus

28. Presumed interconnections of speech areas Central Sulcus 12 3 4 1 – Phonological production 2 – Articulation 3 – Articulatory monitoring 4 – Phonological monitoring 5 – Primary auditory 6 – Phonological recognition Post-Central Sulcus 6 5

29. And there’s more than meets the eye  The phonological recognition area includes the temporal plane  The phonological monitoring area includes the parietal operculum  Both large areas

30. The Sylvian Fissure REVIEW

31. Evidence for left pSTP involvement in speech production  Erratic speech of Wernicke’s aphasics  Conduction aphasia from damage to left pSTP  Intraoperative stimulation of left pSTP “distortion and repetition of words and syllables” (Penfield & Roberts 1959) N.B.: As in Wernicke’s aphasia  MSI study shows activity in left pSTG just before speech production (picture naming) (Levelt et al. 1998)  fMRI study: similar results – no RH activity shown (Hickok et al. 1999) (Hickok 2000: 93-4) REVIEW

32. An MSI study from Max Planck Institute Levelt, Praamstra, Meyer, Helenius & Salmelin, J.Cog.Neuroscience 1998

33. Diffusion Tensor Imaging (DTI)  New and very informative technique  Uses MRI  Allows observation of molecular diffusion in living tissues  Makes use of Brownian movement Magnetic properties of hydrogen nuclei  Two of them in every water molecule (H 2 O)  Water moves along lines of least resistance i.e., along white matter axons  aided by myelin

34. Uniformity of cortical strucure across mammals?  The hypothesis of uniformity Very important for perceptual neuroscience Allows data from experiments on cats and monkeys to be applied to human cortical structure and function  Including higher levels – language  But: this hypothesis applies to grey matter Not white matter  Cortico-cortical connections  DTI shows that white matter connections differ across mammals

35. Arcuate fasciculus in different primates Asif Ghazanfar, Nature Neuroscience 11:4.382-384, April 2008

36. Friederici Fig. 1 Syntactic networks in the human brain. (a) Depicts the two neural networks for syntactic processing and their fronto- temporal involvement (function) schematically. (b) Shows fiber tracting as revealed by DTI (structure) in an individual subject: top right, with the starting point (green dot) being BA 44 and bottom right, with the starting point (blue dot) being the frontal operculum.

37. Friederici figure: Brodmann areas in LH

38. Friederici Figure 2 Fiber tracts between Broca's and Wernicke's area. Tractography reconstruction of the arcuate fasciculus using the two-region of interest approach. Broca's and Wernicke's territories are connected through direct and indirect pathways. The direct pathway (long segment shown in red) runs medially and corresponds to classical descriptions of the arcuate fasciculus. The indirect pathway runs laterally and is composed of an anterior segment (green), connecting Broca's territory and the inferior parietal cortex (Geschwind's territory), and a posterior segment (yellow), connecting Geschwind's and Wernicke's territories.

39. What?!!! Combining functional MRI and DTI, two of these pathways were defined as being relevant for syntactic processes [44]. Functionally, two levels of syntactic processing were distinguished, one dealing with building a local phrase (i.e. a noun phrase consisting of a determiner and a noun ‘the boy’) and one dealing with building complex, hierarchically structured sequences (like embedded sentences ‘This is the girl who kissed the president’). DTI data [44] revealed that the frontal operculum supporting local phrase structure building [14] and [44] was connected via the UF to the anterior STG which has been shown to be involved in phrase structure building as well [14]. The dorsal pathway connects BA 44 which supports hierarchical structure processing [42] and [45], via the SLF to the posterior portion of the STG/STS, which is known to subserve the processing of syntactically complex sentences 51 I. Bornkessel et al., Who did what to whom? The neural basis of argument hierarchies during language comprehension, Neuroimage 26 (2005), pp. 221–233. Article | PDF (300 K) | View Record in Scopus | Cited By in Scopus (53)[51]. This latter network was, therefore, taken to have a crucial role in the processing of syntactically complex, hierarchically structured sentences. (Friederici 2009, p. 179)[44] [14][44][14][42][45]51ArticlePDF (300 K)View Record in ScopusCited By in Scopus (53)[51]

40. Hickok on phonological working memory “… Broca’s area and the SMG are involved in speech perception only indirectly through their role in phono- logical working memory which may be recruited during the performance of certain speech perception tasks.” Hickok 2000: 97 “The sound-based system interfaces not only with the conceptual knowledge system, but also with frontal motor systems via an auditory-motor interface system in the inferior parietal lobe. This circuit is the primary substrate for phonological working memory, but also probably plays a role in volitional speech production. Hickok 2000: 99

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