Connections of Grasping and Horizontal Hand Movements with Articulation in Czech Speakers

Abstract

We have recently shown in Finnish speakers that articulation of certain vowels and consonants has a systematic influence on simultaneous grasp actions as well as on forward and backward hand movements. Here we studied whether these effects generalize to another language, namely Czech. We reasoned that if the results generalized to another language environment, it would suggest that the effects arise through other processes than language-dependent semantic associations. Rather, the effects would be likely to arise through language-independent interactions between processes that plan articulatory gestures and hand movements. Participants were presented with visual stimuli specifying articulations to be uttered (e.g., A or I), and they were required to produce a manual response concurrently with the articulation. In Experiment 1 they responded with a precision or a power grip, whereas in Experiment 2 they responded with a forward or a backward hand movement. The grip congruency effect was fully replicated: the consonant [k] and the vowel [α] were associated with power grip responses, while the consonant [t] and the vowel [i] were associated with precision grip responses. The forward/backward congruency effect was replicated with vowels [α], [o], which were associated with backward movement and with [i], which was associated with forward movement, but not with consonants [k] and [t]. These findings suggest that the congruency effects mostly reflect interaction between processes that plan articulatory gestures and hand movements with an exception that the forward/backward congruency effect might only work with vowel articulation.

Reaching and grasping with the tongue: Shared motor planning between hand actions and articulatory gestures

“…This articulation-movement effect was observed even though the participants were not required to explicitly process the frontness/backness dimension of the vowel, they were entirely unaware about the objectives of the study, and most of them did not even know that, for example, [i] is more a frontal vowel than [o]. Moreover, we have more recently observed the same effect in Czech speakers (Tiainen, Lukavský, Tiippana, Vainio, Šimko, Felisberti & Vainio, 2017). These studies suggest that people have an implicit and language-independent tendency to link forward hand movements with front-close vowels and backward hand movements with back-open and back-mid-open vowels.…”

The Sound of Grasp Affordances: Influence of Grasp‐Related Size of Categorized Objects on Vocalization

“…Errors (i.e., the participant uttered the wrong speech unit or did not produce any response) and RTs more than two standard deviations from each participant's condition means were excluded from the reaction time analysis . It is noteworthy that a 2 SD cutoff procedure is a valid and frequently used statistical tool (Singh, ) that we have previously used in all our studies that have measured reaction times of manual and vocal responses (e.g., Tiainen, Lukavský, et al, ; Vainio, Rantala, et al, ; Vainio et al, ; Vainio, Tiainen, et al, ). Of the trials, 2% were removed as errors and 4.4% were removed as outliers.…”

“…Experiment 1 showed that even though the unvoiced consonants of [t] and [k] are connected to the precision and power grips, respectively (Tiainen, Lukavský, et al, ; Vainio et al, ), their pronunciation is not influenced by the categorization of objects whose size is congruent with these grip types. That is, a statistically significant interaction between Size and Response was missing in the consonant data.…”

“…Previous research has also revealed that programming of the precision and power grips is linked to processes responsible for programming specific articulatory gestures (e.g., Gentilucci, Stefanini, Roy, & Santunione, ). For example, when participants are required to perform simultaneous vocalizations and grip responses, articulation of the front‐closed vowel [i] facilitates the precision grip responses, whereas articulation of the back‐open vowel [ɑ] facilitates the power grip responses (Tiainen, Lukavský, et al, ; Tiainen, Tiippana, Vainio, Komeilipoor, & Vainio, ; Vainio, Schulman, Tiippana, & Vainio, ; Vainio, Tiainen, Tiippana, & Vainio, ; Vainio, Tiippana, Tiainen, Rantala, & Vainio, ). Given that grasp‐related object affordances automatically activate the congruent grasp action, and that the two grasp motor programs appear to be connected to articulation of specific vowels, it is possible that viewing objects graspable with the precision or power grip could have a systematic influence on vocalization.…”

“…Previous studies have also shown that when participants are required to pronounce the apical stop consonant [t] or the dorsal stop consonant [k], in the context of consonant‐vowel (CV) syllables (i.e., [te] and [ke]), simultaneously with producing the precision or power grip responses, the manual and vocal responses are facilitated when [t] is produced with the precision grip and the [k] is produced with the power grip (Tiainen, Lukavský, et al, ; Vainio et al, ). According to Vainio et al (), regarding the consonant [t], the effect might be observed because the final shape of the tongue in relation to [t], and the final shape of the hand in relation to the precision grip, are both achieved by moving the tip of the distal effector (thumb/tongue) into contact with other part of the distal effector (tip of the index finger/back of upper‐central incisors).…”