# Increased Entropic Brain Dynamics during DeepDream-Induced Altered Perceptual Phenomenology

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## Abstract

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## 1. Introduction

## 2. Materials and Methods

#### 2.1. Participants

#### 2.2. Stimuli and Procedure

#### 2.3. EEG Acquisition and Preprocessing

#### 2.4. Entropy and Complexity Analysis of the EEG Signal

#### 2.5. Functional Connectivity Networks and Geodesic Entropy Estimation

#### 2.6. Statistical Analysis

## 3. Results

#### 3.1. Entropy and Complexity

#### 3.2. Global Functional Connectivity and Geodesic Entropy

## 4. Discussion

## Supplementary Materials

**A**) MPE values for DD and OR along the time scales in the frontal, temporo-parietal and occipital ROI. Shaded areas represent standard error of the mean. Gray lines indicate statistical significance (p < 0.05, cluster corrected). (

**B**) MJSC values for DD and OR along the time scales in the frontal, temporo-parietal and occipital ROI. Shaded areas represent standard error of the mean. Gray lines indicate statistical significance (p < 0.05, cluster corrected). (

**C**) Topographic maps depicting the MPE of DD and OR in the significant time scale range 6–16. (

**D**) Topographic maps depicting the MJSC of DD and OR in the significant time scale range 7–17. Figure S2: (

**A**) pLZC values for DD and OR along the time scales in the frontal, temporo-parietal and occipital ROI. Shaded areas represent standard error of the mean. (

**B**) mLZC values for DD and OR along the time scales in the frontal, temporo-parietal and occipital ROI. Shaded areas represent standard error of the mean.

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**(

**A**) Visual representation of the architecture of GoogleNet. (

**B**) General description of the DeepDream algorithm. (

**C**) Examples of frames from the OR and DD videos. (

**D**) Schematic representation of the time course of the experiment.

**Figure 2.**(

**A**) MWPE values for DD and OR along the time scales in the frontal, temporo-parietal and occipital ROI. Shaded areas represent standard error of the mean. Gray lines indicate statistical significance (p < 0.05, cluster corrected). (

**B**) MWJSC values for DD and OR along the time scales in the frontal, temporo-parietal and occipital ROI. Shaded areas represent standard error of the mean. Gray lines indicate statistical significance (p < 0.05, cluster corrected). (

**C**) Topographic maps depicting the MWPE of DD and OR in the significant time-scale range 7–17. (

**D**) Topographic maps depicting the MWJSC of DD and OR in the significant time scale-range 11–19.

**Figure 3.**Entropy complexity hyperplane (ECH) showing MWPE and MWJSC values conjunctively across the time scales. Red and blue lines represent average values for DD and OR. Colored dots are participants’ values. Green line indicates the performance of the LDA classifier. Shaded areas represent standard error of the mean. Black lines indicate statistical significance (p < 0.05, cluster corrected).

**Figure 4.**(

**A**) Raincloud plots showing GFC values in the alpha, beta and gamma bands between DD and OR. Asterisk indicates statistical significance (p < 0.05). (

**B**) Raincloud plots showing AGE values in the alpha, beta and gamma bands between DD and OR. Asterisk indicates statistical significance (p < 0.05). (

**C**) Functional connectivity networks in the alpha, beta and gamma bands represented as topographic connectivity plots. (

**D**) Topographic maps showing sensor GE in DD and OR in the alpha, beta and gamma bands.

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**MDPI and ACS Style**

Greco, A.; Gallitto, G.; D’Alessandro, M.; Rastelli, C.
Increased Entropic Brain Dynamics during DeepDream-Induced Altered Perceptual Phenomenology. *Entropy* **2021**, *23*, 839.
https://doi.org/10.3390/e23070839

**AMA Style**

Greco A, Gallitto G, D’Alessandro M, Rastelli C.
Increased Entropic Brain Dynamics during DeepDream-Induced Altered Perceptual Phenomenology. *Entropy*. 2021; 23(7):839.
https://doi.org/10.3390/e23070839

**Chicago/Turabian Style**

Greco, Antonino, Giuseppe Gallitto, Marco D’Alessandro, and Clara Rastelli.
2021. "Increased Entropic Brain Dynamics during DeepDream-Induced Altered Perceptual Phenomenology" *Entropy* 23, no. 7: 839.
https://doi.org/10.3390/e23070839