Comprehension of Prosodic Cues in Typical & Atypical Populations

1. Comprehension of Prosodic Cues in Typical & Atypical Populations Dr. Rachel Mitchell Dept. of Psychology, Durham Univ.

2. What is prosody? • Higher order language function: • Paralinguistic or pragmatic phenomenon that accompanies words & can modify or influence meaning • (Suprasegmental) features of speech such as intonation, loudness, & tempo • Conveyed by gradient features e.g. pitch height & range, & rhythmicity • “That faculty of speech which conveys different shades of meaning by means of variations in stress + pitch – irrespective of the words + grammatical construction” (Monrad-Kohn, 1947).

3. What’s its role in language? • Intrinsic prosody: dialectical and idiosyncratic differences, question vs. declarative statement • Intellectual prosody: speaker attitude about info conveyed (enthusiasm, boredom etc) • Emotional prosody: emotion conveyed (happiness, fear etc) • Inarticulate prosody: nonlinguisticsounds (sighs, groans etc)

4. Why is it important? • Crucial to understanding true communicative intent (societal integration) • How something said as imp. as what’s said (sarcasm etc) • Deficits impair ability to interpret others’ emotional states & behave in socially appropriate manner (Trauner et al., 1996) • Ability to interpret auditory emotion cuesplays important role in maintaining successful relationships & healthy psychological fx (Carton et al., 1999).

5. What happens in the brain? • Mitchell et al. (2003) Neuropsychologia, 41(10), 1410-1421. • Variable lesion studies: R hem damage not always disruptive, sometimes L hem damage, multiple skills across both hem’s • Solely associated with early association cortex unlikely • Stimuli: H & S sentences, H, S & N intonation • Pure: MTG (R>L), L MFG • Cong v rest: R STG, R MFG, L SFG, CG • Cong v neutral: R MTG, R IFG, LSTG • Incong v rest: MTG (R>L) • Attend semantics: R STG, L SPL, L MFG, L ITG, L SPL • Attend prosody: R MTG, R MedFG

6. How do we process mixed signals? • Mitchell R (2006) Cognitive, Affective & Behavioral Neurosci, 6(4), 298-305. • Modulation of speech content by prosody. • Why wouldn’t conflicting cues have similar effects to Stroop tasks? • Congruence effects? Yes • Relative importance of semantics & prosody. No effect • Mitchell R (2006) EurJ Neurosci, 24(12), 3611-18 • Activation of conflict regions? - dlPFC, ACC • - See next slide • Modulation of ‘prosodic emotion’ regions? - Attention influences activity in sensory cortical regions assoc with specific modality. • - R lat T lobe ROI parameter estimates suggest lower activity in interference contrast than in facilitation contrast

8. Why do neuroimaging and lesion studies differ? • Ross & Mesulam(1979) • 2 R-handed patients with frontoparietal ischemic strokes • Neither aphasic but displayed flattened affective demeanour • Ability to identify emotion portrayed in normal speech unaffected •  series papers confirmed association, while damage involving posterior T region associated with inability to comprehend affective prosody • Organisation prosodic functions in R hem mirrors propositional language functions in L? Unexpected F lobe activations in early neuroimaging studies. Schirmer & Kotz (2006) 3 stage model • Can TMS resolve this discrepancy? (LUCY ALBA-FERRARA)

9. What happens when we age? • Mitchell R (2007) CognEmot, 21(7), 1435 – 54 • Ageing affects facial emotion recognition • Brosgole & Weisman (1995) asymptote age 12, maintain until mid age (mid 40s), then ↓ age 65+ - resembles 3-to-6 yr olds • Theoretical doubts: lifetime of practice • Mediators and mechanisms: • Frontal Lobe Load (N-back task) • Hearing sensitivity (Pure Tone Average) • IQ (NART) – only covariate • Depression (Beck Depression Iventory) • Verbal Working Memory (Daneman & Carpenter) • Aged 61 to 83  chronological age covariate

10. How specific is this? • Are prosodic emotion decoding deficits caused by inability to generally decode prosodic cues? • Compare emotional prosody with non-emotional prosody (e.g. changes in stress that distinguish bet declarative & question) • Which constituents of emotional prosody do older adults have particular difficulty processing? • Are prosodic emotion decoding deficits caused by inaccurate processing of elemental constituents?

11. What are the Consequences? • Little explicit investigation in normal populations • Aim = determine which aspects social well-being decline in tandem with age-related decline • Study A. • Which aspects social well-being associated with norm variations in ability to decode prosodic emotion? • Which aspects decline in tandem with age-related decline? • Study B. • Does depressed mood in older adults leads to prosodic emotion comprehension dysfunction or v.v.? • Depressed mood may be means by which poor comprehension exerts effects on social function. • Low social function often correlated with depressed mood in older adults

12. What happens in schizophrenia?

13. Healthy controls L: Z=4.25, 188 voxels R: Z=4.42, 362 voxels Schizophrenia L: Z=3.76, 455 voxels R: Z=3.17, 10 voxels Z=3.95, 329 voxels Bipolar Disorder L: Z=5.20, 1090 voxels R: Z=3.47, 27 voxels Z=5.03, 665 voxels Experiment 1Filtered emotional prosody vs. rest

14. Experiment 2Unfiltered emotional prosody vs. rest Schizophrenia L: Z=3.46, 293 voxels Z=3.88, 51 voxels R: Z=3.64, 61 voxels Z=3.54, 153 voxels Healthy controls L: Z=4.52, 819 voxels R: Z=5.39, 599 voxels Bipolar Disorder L: Z=4.43, 792 voxels R: Z=4.13, 569 voxels

15. Experiment 3 • Attention to semantics: • HC activated large network L hemisphere regions, S did not • BP didn’t activate any regions in within-group analyses but not abnormal in between-group analyses • Attention to emotional prosody: • S activated large network R hemisphere regions, HC did not • BP didn’t activate any regions in within-group analyses but not abnormal in between-group analyses

16. What happens in Parkinson’s disease? • Patients with PD may find it more difficult to ‘read’ emotion signals transmitted via tone of voice. • PD neuropathology suggests altered basal ganglia function may explain this, but it could be explained by altered frontal lobe function instead. • Patients with PD performed 4 tasks: • A standard task of working (‘online’) memory • An emotion version of task 1 • A standard attention task • An emotion version of task 3 • Patients not worse on emotion tasks than older adults, even when tasks demanding  only when frontal lobe pathology above a threshold? • But, PD patients didn’t perform standard tasks as well  more prominent?

17. Laterality and intensity issues • Lateralisation • Motor symptoms usually worse on one side of body. • Tone of voice findings inconsistent – a subgroup only? • Word content mediated by L half brain, emotional tone of voice by R half. • Would expect different patterns behaviour depending whether pathology in L or R half brain. • e.g. visuo-spatial problems in patients whose L side body affected • Compare comprehension word content with comprehension tone of voice. • Patients studied initially in on and off state medication 

18. Intensity • Sensitivity to emotional tone of voice in sentences • Sensitivity to non-emotional tone of voice in sentences • Sensitivity to emotional prosody in words • Sensitivity to facial emotions • Sensitivity to varying degrees of facial emotion. • We will adjust the data for changes in response speed. • Explore Medication level, Chronicity of disease, Severity motor symptoms

19. New directions • ?