Switch or stay? Automatic classification of internal mental states in bistable perception

Sen, Susmita; Daimi, Syed Naser; Watanabe, Katsumi; Takahashi, Kohske; Bhattacharya, Joydeep and Saha, Goutam. 2020. Switch or stay? Automatic classification of internal mental states in bistable perception. Cognitive Neurodynamics, 14(1), pp. 95-113. ISSN 1871-4080 [Article]

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Abstract or Description

The human brain goes through numerous cognitive states, most of these being hidden or implicit while performing a task,
and understanding them is of great practical importance. However, identifying internal mental states is quite challenging as
these states are difficult to label, usually short-lived, and generally, overlap with other tasks. One such problem pertains to
bistable perception, which we consider to consist of two internal mental states, namely, transition and maintenance. The
transition state is short-lived and represents a change in perception while the maintenance state is comparatively longer and
represents a stable perception. In this study, we proposed a novel approach for characterizing the duration of transition and
maintenance states and classified them from the neuromagnetic brain responses. Participants were presented with various
types of ambiguous visual stimuli on which they indicated the moments of perceptual switches, while their magnetoencephalogram
(MEG) data were recorded. We extracted different spatio-temporal features based on wavelet transform, and
classified transition and maintenance states on a trial-by-trial basis. We obtained a classification accuracy of 79.58% and
78.40% using SVM and ANN classifiers, respectively. Next, we investigated the temporal fluctuations of these internal
mental representations as captured by our classifier model and found that the accuracy showed a decreasing trend as the
maintenance state was moved towards the next transition state. Further, to identify the neural sources corresponding to
these internal mental states, we performed source analysis on MEG signals. We observed the involvement of sources from
the parietal lobe, occipital lobe, and cerebellum in distinguishing transition and maintenance states. Cross-conditional
classification analysis established generalization potential of wavelet features. Altogether, this study presents an automatic
classification of endogenous mental states involved in bistable perception by establishing brain-behavior relationships at
the single-trial level.

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Additional Information:

SS was supported by MHRD, Govt. of India. The funders had no role in study design, data collection, and analysis, decision to publish, or preparation of the manuscript.


Internal mental states, Bistable perception, MEG Single-trial classification, Source reconstruction, SVM, ANN

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6 July 2019Accepted
19 July 2019Published Online
February 2020Published

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Date Deposited:

22 Jul 2019 09:23

Last Modified:

24 Jan 2020 10:30

Peer Reviewed:

Yes, this version has been peer-reviewed.



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