Table 6.
Studies on the impact of cognitive load on voice and speech production.
| Study | Speech process | Subjects | Context | Task | Speech measures | Results |
|---|---|---|---|---|---|---|
| Griffin and Williams, 1987 | Phonation | N = 20 | Laboratory | Psychomotor tests, increased difficulty. | F0 Amplitude in dB Word duration | Level 4 caused: |
| • Level 1 counting from 1 to 10 for 10 times. | • Significantly increased F0 (106.95–118.91 Hz) | |||||
| • Level 2: psychomotor test (PMT) while counting 0–9. | • Increased intensity (49.38–57.12 dB). | |||||
| • Level 3: simple dichotic listening task (DLT) with vocalized responses. | • Decreased word duration (384.81–338.80 ms). | |||||
| • Level 4: combined DLT-PMT task. | ||||||
| Hecker et al., 1968 | Phonation | N = 5 | Laboratory | Time-constraints in a read-aloud calculation task. | F0 | Mixed results: increased and decreased F0-patterns. |
| Huttunen et al., 2011 | Phonation | N = 13 | Simulation flight | Flight simulation task with three levels of cognitive load: situation awareness, information processing and decision making. | F0 F0 range amplitude | • Increased F0 and amplitude in function of cognitive load. |
| • Decreased F0 range. | ||||||
| Kurniawan et al., 2013 | Phonation | Not mentioned – model testing | laboratory | • BL: questionnaire and 10 min relaxation. | F0 prediction models | No reliable predictive models in F0. |
| • Low cognitive load: Stroop-Word congruent color test and easy mental-math test. | Voice stress is an individual dependent factor. | |||||
| • High cognitive load: Stroop-Word incongruent color test and hard mental-math tests. | ||||||
| Johannes et al., 2007 | Phonation | N = 11 | Laboratory | Psychomotor tests: time pressure, problem solving test, sensorimotor coordination and a handgrip physical strength test) with alternated relaxation (nature images with composed music). | F0 | • Increased F0 in time pressure and problem solving tasks. |
| Rothkrantz et al., 2004 | Breathing Phonation | N = 108 | Laboratory | Stroop-task with increased difficulty: shortening the time between the appearances of the presentation of the matched and non-matched color-word sample every minute with half a second. | F0 Jitter Duration | • Significant increased F0 (114.28–122.20 Hz) and F0-variation (7.36–10.11 Hz). |
| • Significant decreased jitter (1.24–0.94%). | ||||||
| • Significant decrease in jitter (1.24–0.94%). | ||||||
| • High frequency energy more present in longer time-slots. | ||||||
| • Decreased utterance duration. | ||||||
| Ruiz et al., 1996 | Phonation | N = 1 | Laboratory | Stroop-task. | F0 Formants F1, F2, F3 | • Significant increase in F0 (127–164.8 Hz with a maximal peak value of 250 Hz). |
| • Impact on formants vowel specific. |