Amy E. Hayes

Vision-for-action: The effects of object property discrimination and action state on affordance compatibility effects

When a person views an object, the action the object evokes appears to be activated independently of the person’s intention to act. We demonstrate two further properties of this vision-to-action process. First, it is not completely automatic, but is determined by the stimulus properties of the object that are attended. Thus, when a person discriminates the shape of an object, action affordance effects are observed; but when a person discriminates an object’s color, no affordance effects are observed. The former, shape property is associated with action, such as how an object might be grasped; the latter, color property is irrelevant to action. Second, we also show that the action state of an object influences evoked action. Thus, active objects, with which current action is implied, produce larger affordance effects than passive objects, with which no action is implied. We suggest that the active object activates action simulation processes similar to those proposed in mirror systems.

Sensorimotor fluency influences affect: Evidence from electromyography

Fluency of visual processing induces affective responses, with easier-to-process stimuli being preferred (Winkielman & Cacioppo, 2001). The present study extends this research to the motor domain by investigating the effect of sensorimotor fluency on affective reactions to objects in a categorisation task. In fluent stimulus–response (s–r) trials, grasp-compatible objects were presented on the same side of the screen as the response hand; in non-fluent trials, grasp incompatible objects were presented on the opposite side of the screen to the response hand. Affective responses were measured implicitly using face muscle activity (electromyography). As predicted, participants exhibited greater cheek muscle activity (associated with smiling) in trials with s–r compatible responses compared with incompatible responses. These findings support hedonic models of fluency in which fluent processing elicits direct emotional experience, and suggest that models of hedonic fluency should take into account the integration of the motor system in visual processing.

Lack of inhibition in Parkinson's disease: evidence from a lexical decision task ☆

Persons affected by Parkinsons disease (PD) often show an increased semantic priming effect from target words in lexical decision tasks (hyper-priming) as compared to age-matched controls. In this study, a lexical decision task was used to investigate both semantic priming (Experiment 1) and repetition priming (Experiment 2) from distractor words in PD patients and age-matched controls. With this negative priming procedure, target words in successive trials are never related, and therefore participants always have to switch between unrelated target words. Instead, it is the distractor prime word that is either related or unrelated to the subsequent target, giving the measure of priming. Results showed that PD patients demonstrated a robust effect of positive semantic priming from distractor words. Participants from the control group did not show any semantic priming effect (positive or negative) from distractors. Similarly, PD patients showed positive repetition priming from distractor words, but the control group showed significant repetition negative priming. These results support the view that the hyper-priming effect typically shown by persons with Parkinsons disease is the result of impaired inhibitory processes required to control word activation during reading.

An electromyographic investigation of the impact of task relevance on facial mimicry

When viewing a face expressing emotion, the viewers face mimics the same emotion. It is unknown whether such facial mimicry takes place when the viewed emotion is a task irrelevant property of the face. The present experiment addressed this question by asking participants to judge either the emotional expression or the colour of a series of happy and angry faces that were either blue or yellow. Electromyographical recordings showed that when emotion was ignored, there was a tendency for facial muscle activity to be suppressed. Nonetheless, participants’ facial expressions mimicked target expressions, with the zygomaticus cheek muscle being more active when viewing a smiling face and the corrugator brow muscle more active when viewing an angry face. These data support the automatic encoding of irrelevant emotional information, as well as suppression of emotional information by selective attention.

The role of emotion in learning trustworthiness from eye-gaze: Evidence from facial electromyography

Gaze direction can be used to rapidly and reflexively lead or mislead others’ attention as to the location of important stimuli. When perception of gaze direction is congruent with the location of a target, responses are faster compared to when incongruent. Faces that consistently gaze congruently are also judged more trustworthy than faces that consistently gaze incongruently. However, it’s unclear how gaze-cues elicit changes in trust. We measured facial electromyography (EMG) during an identity-contingent gaze-cueing task to examine whether embodied emotional reactions to gaze-cues mediate trust learning. Gaze-cueing effects were found to be equivalent regardless of whether participants showed learning of trust in the expected direction or did not. In contrast, we found distinctly different patterns of EMG activity in these two populations. In a further experiment we showed the learning effects were specific to viewing faces, as no changes in liking were detected when viewing arrows that evoked similar attentional orienting responses. These findings implicate embodied emotion in learning trust from identity-contingent gaze-cueing, possibly due to the social value of shared attention or deception rather than domain-general attentional orienting.

Facial mimicry and emotion consistency: Influences of memory and context

This study investigates whether mimicry of facial emotions is a stable response or can instead be modulated and influenced by memory of the context in which the emotion was initially observed, and therefore the meaning of the expression. The study manipulated emotion consistency implicitly, where a face expressing smiles or frowns was irrelevant and to be ignored while participants categorised target scenes. Some face identities always expressed emotions consistent with the scene (e.g., smiling with a positive scene), whilst others were always inconsistent (e.g., frowning with a positive scene). During this implicit learning of face identity and emotion consistency there was evidence for encoding of face-scene emotion consistency, with slower RTs, a reduction in trust, and inhibited facial EMG for faces expressing incompatible emotions. However, in a later task where the faces were subsequently viewed expressing emotions with no additional context, there was no evidence for retrieval of prior emotion consistency, as mimicry of emotion was similar for consistent and inconsistent individuals. We conclude that facial mimicry can be influenced by current emotion context, but there is little evidence of learning, as subsequent mimicry of emotionally consistent and inconsistent faces is similar.

The influence of response grouping on free-choice decision making in a response selection task.

Previous research has demonstrated an advantage for the preparation of fingers on one hand over the preparation of fingers on two hands, and for the preparation of homologous fingers over that of non-homologous fingers. In the present study, we extended the precuing effects observed with finger responses to response selection under free-choice conditions. Participants were required to choose from a range of possible responses following the presentation of a precue that indicated which response to prepare (go-to precue) or prevent (no-go-to precue). In Experiment 1 the choice was between homologous and non-homologous finger responses on the hand opposite to the precue while in Experiment 2 the choice was between finger responses on the same or different hand to the precue. In the go-to precue condition, the frequency of homologous finger choices was more frequent than non-homologous finger responses. Similarly, participants chose finger responses on the same hand as the precue regardless of whether they were instructed to prepare or prevent the precued response. The hand effect bias was stronger than the finger effect bias. These findings are consistent with the Grouping Model (Adam, Hommel, & Umilta, 2003).

Incidental retrieval of prior emotion mimicry

When observing emotional expressions, similar sensorimotor states are activated in the observer, often resulting in physical mimicry. For example, when observing a smile, the zygomaticus muscles associated with smiling are activated in the observer, and when observing a frown, the corrugator brow muscles. We show that the consistency of an individual’s facial emotion, whether they always frown or smile, can be encoded into memory. When the individuals are viewed at a later time expressing no emotion, muscle mimicry of the prior state can be detected, even when the emotion itself is task irrelevant. The results support simulation accounts of memory, where prior embodiments of other’s states during encoding are reactivated when re-encountering a person.

Facial mimicry is modulated by implicit and explicit emotion consistency.

Adapting and integrating to our current environment through physical and social imitation of those around us, such as mimicking facial emotion, often seems to be an automatic and unconscious process. We examined whether the consistency of a persons emotional response can be learned and influence later emotional mimicry. For example, some individuals always express consistent emotions, such as smiling at a positive image whereas other people emote inappropriately, where their emotion is inconsistent, such as smiling at negative images. Is such individual consistency encoded in to memory influencing subsequent mimicry when these consistent and inconsistent people are encountered at a later time? In Study 1 participants implicitly learnt to associate 4 faces as showing consistent emotions, and 4 different faces as showing inconsistent emotions. In Study 2 participants explicitly associated all faces as showing either consistent (2a) or inconsistent (2b) emotions. In both studies participants had facial EMG responses recorded (taken from the corrugator supercilii and zygomaticus major muscles) whilst viewing and categorising each face as smiling or frowning. These recordings were taken to assess how much mimicry was shown toward each face, in relation to the expression and the emotion-consistency of that specific face. In Study 1 EMG results exhibited highly similar mimicry to both consistent and inconsistent emotion faces, despite implicit learning of individual identities and associated emotion consistency. EMG results in Study 2a showed traditional strong mimicry effects to all face emotions. In Study 2b mimicry towards frowns remained but was greatly reduced compared to 2a. No mimicry was shown toward smiles. We conclude that facial mimicry is an automatic process that is nevertheless influenced by context, especially if the context is explicitly created. Meeting abstract presented at VSS 2015.