Warm-up Think of 3 facts about cats that would help to describe cats to someone who does not know what a cat is. 10/21/15Brain & Language - Harry Howard - Tulane University 1

THE VENTRAL STREAM OCT 21, 2015 – DAY 23 Brain & Language LING NSCI Fall 2015

Course organization Fun with I am still working on grading. 10/21/15Brain & Language - Harry Howard - Tulane University 3

ARTICULATORY NET I.3 & II Review 10/21/15Brain & Language - Harry Howard - Tulane University 4

My second revision 10/21/15Brain & Language - Harry Howard - Tulane University 5

10/21/15Brain & Language - Harry Howard - Tulane University 6 Apraxia of speech aka verbal apraxia or dyspraxia Neurogenic phonologic disorder resulting from sensorimotor impairment to the capacity to select, program, and/or execute in coordinated and normally timed sequences, the positioning of speech musculature for the volitional production of speech sounds Prosodic alteration, that is, changes in speech stress, intonation, and/or rhythm, (dysprosody) may be associated with the articulatory disruption either as a primary part of the condition or in compensation for it.

10/21/15Brain & Language - Harry Howard - Tulane University 7 More informally A patient with apraxia of speech know what words he or she wants to say, but has difficulty coordinating the muscle movements necessary to say those words. He or she may say something completely different, even made-up words. For example, a patient may try to say "kitchen," but it may come out "bipem" or even "chicken." The patient may recognize the error and try again, sometimes getting it right, or sometimes saying something else entirely. This can become quite frustrating to him or her.

10/21/15Brain & Language - Harry Howard - Tulane University 8 Symptoms of apraxia of speech A tendency to grope for words or sounds Limited ability to make speech sounds automatically Difficulty putting sounds or syllables together in the correct order to form words Incorrect timing of speech movements and their accompanying sounds Increased tendency to make errors as the length of words or sentences increases Inconsistent speech errors, even when repeating a word that's just been said Errors using vowels A tendency to say a word several times before saying it the right way Inconsistent or improper use of rhythms, stresses, and inflections of speech that are used to convey meaning Somewhat preserved ability to produce "automatic speech" (rote speech), such as greetings like "How are you?"

Hickok (2012) Apraxia of speech (AOS) is a motor speech disorder that seems to affect the planning or coordination of speech at the level that has been argued to correspond to syllable-sized units. The ventral premotor cortex has been implicated in the aetiology of AOS, as has the nearby anterior insula. It is worth noting that speech errors in AOS and conduction aphasia are often difficult to distinguish, the difference being most notable in speech fluency, with AOS resulting in more halting, effortful speech. The similarity in error type and the distinction in fluency between AOS and conduction aphasia is consistent with the present model if one assumes that the two disorders affect the same level of hierarchical motor control (errors occur at the same level of analysis) but in different components of the circuit (AOS affects access to motor phonological codes and conduction aphasia affects internal feedback control). 10/21/15Brain & Language - Harry Howard - Tulane University 9

Motor & somatosensory homunculi 10/21/15Brain & Language - Harry Howard - Tulane University 10

Orofacial, or buccofacial, apraxia Orofacial, or buccofacial, apraxia is characterized by a loss of voluntary control of facial, lingual, pharyngeal and masticatory muscles in the presence of preserved reflexive and automatic functions of the same muscles. It is not considered to have much relevance to language. 10/21/15Brain & Language - Harry Howard - Tulane University 11

THE VENTRAL PATHWAY 10/21/15Brain & Language - Harry Howard - Tulane University 12

The original 10/21/15Brain & Language - Harry Howard - Tulane University 13

Saur et al. (2008) diffusion tensor imaging tractography 10/21/15Brain & Language - Harry Howard - Tulane University 14 Dual pathway network for language. Composite fiber network for repetition (blue) and comprehension (red). Three-dimensional tractography renderings visualize the spatial orientation of both networks to each other. Dashed white line illustrates the bisection of the frontal lobe into a ventral part, which is connected to the postrolandic brain via the ventral pathway and a dorsal part, which is connected to the postrolandic brain via the dorsal pathway.

My third revision 10/21/15Brain & Language - Harry Howard - Tulane University 15

The dorsal pathway: repetition 10/21/15Brain & Language - Harry Howard - Tulane University 16 What is your name?

The ventral pathway: comprehension 10/21/15Brain & Language - Harry Howard - Tulane University 17 my cat

Review of linguistic notation 10/21/15Brain & Language - Harry Howard - Tulane University 18 'æ' [ N cat] (morpho) syntactic [kæt] phonetic cat semantic

The ventral pathway: comprehension 10/21/15Brain & Language - Harry Howard - Tulane University 19 [m-a-i ̯ -k-æ-t] [mai ̯ ] [kæt] mai ̯ kæt mai ̯ kæt [ NP [ Poss mai ̯ ] [ N kæt]] [ma ̯ ikæt]

The process as a list 1. ear 2. auditory cortex 3. STS 4. lexical interface 5. combinatorial net 1 6. combinatorial net 2 1. [mai ̯ kæt] 2. [m-a-i ̯ -k-æ-t] 3. [mai ̯ ] [kæt] 4. mai ̯ kæt 5. mai ̯ kæt 6. [ NP [ Poss mai ̯ ] [ N kæt]] 10/21/15Brain & Language - Harry Howard - Tulane University 20

The ventral pathway: interaction 10/21/15Brain & Language - Harry Howard - Tulane University 21 What is your name? Harry.

Final project Improve a Wikipedia article about any of the topics mentioned in class or any other topic broadly related to neurolinguistics. Write a short essay explaining what you did and why you did it. Print the article before you improve it, highlighting any subtractions. Print the article after you improve it, highlighting your additions. 10/21/15Brain & Language - Harry Howard - Tulane University 22

NEXT TIME The lexical interface: word semantics 10/21/15Brain & Language - Harry Howard - Tulane University 23