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Affective Interaction with a Virtual Character Through an fNIRS Brain-Computer Interface.

Aranyi G, Pecune F, Charles F, Pelachaud C, Cavazza M - Front Comput Neurosci (2016)

Bottom Line: We use for affective input the asymmetric activity in the dorsolateral prefrontal cortex (DL-PFC), which has been previously found to be related to the high-level affective-motivational dimension of approach/avoidance.We carried out an experiment with 18 subjects, which demonstrated that subjects are able to successfully engage with the virtual agent by controlling their mental disposition through NF, and that they perceived the agent's responses as realistic and consistent with their projected mental disposition.Overall, our contribution reconciles a model of affect derived from brain metabolic data with an ecologically valid, yet computationally controllable, virtual affective communication environment.

View Article: PubMed Central - PubMed

Affiliation: School of Computing, Teesside University Middlesbrough, UK.

ABSTRACT
Affective brain-computer interfaces (BCI) harness Neuroscience knowledge to develop affective interaction from first principles. In this article, we explore affective engagement with a virtual agent through Neurofeedback (NF). We report an experiment where subjects engage with a virtual agent by expressing positive attitudes towards her under a NF paradigm. We use for affective input the asymmetric activity in the dorsolateral prefrontal cortex (DL-PFC), which has been previously found to be related to the high-level affective-motivational dimension of approach/avoidance. The magnitude of left-asymmetric DL-PFC activity, measured using functional near infrared spectroscopy (fNIRS) and treated as a proxy for approach, is mapped onto a control mechanism for the virtual agent's facial expressions, in which action units (AUs) are activated through a neural network. We carried out an experiment with 18 subjects, which demonstrated that subjects are able to successfully engage with the virtual agent by controlling their mental disposition through NF, and that they perceived the agent's responses as realistic and consistent with their projected mental disposition. This interaction paradigm is particularly relevant in the case of affective BCI as it facilitates the volitional activation of specific areas normally not under conscious control. Overall, our contribution reconciles a model of affect derived from brain metabolic data with an ecologically valid, yet computationally controllable, virtual affective communication environment.

No MeSH data available.


The distribution of block success across subjects.
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Figure 6: The distribution of block success across subjects.

Mentions: Based on their NF performance, we classified subjects as respondents (completed at least one block successfully) and non-respondents (completed no successful blocks). Fifteen of the seventeen valid subjects (88%) were classified as respondents. Additionally, the two non-respondents were not simply failed on the statistical criterion; they have not crossed the feedback threshold at all during the experiment (i.e., received no feedback whatsoever). Eleven out of the 15 respondents (73%) completed at least half of the blocks successfully (Median = 4). No subject completed all blocks successfully (Figure 6). This success rate on the subject basis is identical to what we observed in a separate study applying the same NF protocol (Charles et al., 2015).


Affective Interaction with a Virtual Character Through an fNIRS Brain-Computer Interface.

Aranyi G, Pecune F, Charles F, Pelachaud C, Cavazza M - Front Comput Neurosci (2016)

The distribution of block success across subjects.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4940367&req=5

Figure 6: The distribution of block success across subjects.
Mentions: Based on their NF performance, we classified subjects as respondents (completed at least one block successfully) and non-respondents (completed no successful blocks). Fifteen of the seventeen valid subjects (88%) were classified as respondents. Additionally, the two non-respondents were not simply failed on the statistical criterion; they have not crossed the feedback threshold at all during the experiment (i.e., received no feedback whatsoever). Eleven out of the 15 respondents (73%) completed at least half of the blocks successfully (Median = 4). No subject completed all blocks successfully (Figure 6). This success rate on the subject basis is identical to what we observed in a separate study applying the same NF protocol (Charles et al., 2015).

Bottom Line: We use for affective input the asymmetric activity in the dorsolateral prefrontal cortex (DL-PFC), which has been previously found to be related to the high-level affective-motivational dimension of approach/avoidance.We carried out an experiment with 18 subjects, which demonstrated that subjects are able to successfully engage with the virtual agent by controlling their mental disposition through NF, and that they perceived the agent's responses as realistic and consistent with their projected mental disposition.Overall, our contribution reconciles a model of affect derived from brain metabolic data with an ecologically valid, yet computationally controllable, virtual affective communication environment.

View Article: PubMed Central - PubMed

Affiliation: School of Computing, Teesside University Middlesbrough, UK.

ABSTRACT
Affective brain-computer interfaces (BCI) harness Neuroscience knowledge to develop affective interaction from first principles. In this article, we explore affective engagement with a virtual agent through Neurofeedback (NF). We report an experiment where subjects engage with a virtual agent by expressing positive attitudes towards her under a NF paradigm. We use for affective input the asymmetric activity in the dorsolateral prefrontal cortex (DL-PFC), which has been previously found to be related to the high-level affective-motivational dimension of approach/avoidance. The magnitude of left-asymmetric DL-PFC activity, measured using functional near infrared spectroscopy (fNIRS) and treated as a proxy for approach, is mapped onto a control mechanism for the virtual agent's facial expressions, in which action units (AUs) are activated through a neural network. We carried out an experiment with 18 subjects, which demonstrated that subjects are able to successfully engage with the virtual agent by controlling their mental disposition through NF, and that they perceived the agent's responses as realistic and consistent with their projected mental disposition. This interaction paradigm is particularly relevant in the case of affective BCI as it facilitates the volitional activation of specific areas normally not under conscious control. Overall, our contribution reconciles a model of affect derived from brain metabolic data with an ecologically valid, yet computationally controllable, virtual affective communication environment.

No MeSH data available.