Robot-Touch Promotes Memory Sensitization

Round 1

Reviewer 1 Report

The proposed research is properly structured and clearly described. Results are of interest. Further experimental activities are encouraged to broad the analysis and develope a more consistent and complete understanding of the addressed psychological and societal phenomena. In particular more complex human-robot interactions in different settings and a larger population could be considered in the experimental trials.

The paper is properly structured and the methodology, experiments and results are clearly illustrated.

Major limitation is that it is based on a quite reduced experimental campaign, therefore I'd strongly recommend a larger experimental campaign to further deepen and argue the results and their implications in the near future.

Since I assume that such a request is quite demanding for the authors, may be they could at present revise their paper by integrating a section in the concluding remarks explaining the possible future experimental campaigns they are planning or would propose others to execute in order to further develop the proposed research approach, illustrating also the specific objectives and added value of such needed future experiments.

In any case, even if so far with a limited experimental campaign, the paper is of interest for the scientific community, based on its actual outcomes and conclusions.

Author Response

First and foremost, we are thankful for the reviewer’s time and kind consideration to review the present manuscript. Reviewer’s comments substantially improved the quality of the present study and its presentation.

In what follows, point-by-point responses to reviewer’s comments and concerns are provided.

Sincerely,

Reviewer 1

Reviewer’s Comment: Major limitation is that it is based on a quite reduced experimental campaign, therefore I'd strongly recommend a larger experimental campaign to further deepen and argue the results and their implications in the near future.

Since I assume that such a request is quite demanding for the authors, may be they could at present revise their paper by integrating a section in the concluding remarks explaining the possible future experimental campaigns they are planning or would propose others to execute in order to further develop the proposed research approach, illustrating also the specific objectives and added value of such needed future experiments.

Author’s Response: We thank the reviewer for this important note that we missed in the first version of the manuscript. We addressed it in the newly added Section 5. Concluding Remarks, lines 470-487 as follows.

“The small number of participants in the present study who were from a single demographic background (i.e., 30 younger Japanese adults) limit the generalizability of its findings. Future research can address these limitations by including larger sample of gender-diverse individuals from various cultural backgrounds and age range (i.e., children, adolescents, and older individuals in addition to younger adults only). Such diversified studies will allow for more informed conclusions via broader examination of the potential effect of age, culture, and gender on present findings.

Another venue in which the future research can further the present findings is through adaptation of different types of robots for touch interaction to verify how such variety may affect the perception of physical interaction by human subjects. For instance, these studies may consider the change in degree of trust, likeability, etc. by human subjects as a function of varying level of human-likeness of such physically interacting agents. In the same vein, they may also compare the human-likeness versus more animal-like look-and-feel to verify how such a change in appearance could help in addressing human subjects' affective stance toward robots.”

Author Response File: Author Response.pdf

Reviewer 2 Report

The paper presents an interesting and important problem of robot-touch in social robot - human interaction. The paper is very well organized with detailed steps of experiments and discussion. 

English spell check is needed. e.g line 469 "All subjects singed..." should be " signed"

The paper only used 30 young adults for experiments. The samples (dataset) are not large and diverse. More samples are needed. Furthermore, it will be more interesting to divide samples into, for example, elder, young adult, children. And then see the results with different age ranges and/or genders. 

Author Response

First and foremost, we are thankful for the reviewer’s time and kind consideration to review the present manuscript. Reviewer’s comments substantially improved the quality of the present study and its presentation.

In what follows, point-by-point responses to reviewer’s comments and concerns are provided.

Sincerely,

Reviewer 2

 Reviewer’s Comment: English spell check is needed. e.g line 469 "All subjects singed..." should be " signed"

Author’s Response: We corrected this spelling mistake (line 490, in the current version of manuscript) and also checked and corrected for any other possible mistakes/typos.

Reviewer’s Comment: The paper only used 30 young adults for experiments. The samples (dataset) are not large and diverse. More samples are needed. Furthermore, it will be more interesting to divide samples into, for example, elder, young adult, children. And then see the results with different age ranges and/or genders. 

Author’s Response: We thank the reviewer for this important note that we missed in the first version of the manuscript. We addressed it in the newly added Section 5. Concluding Remarks, lines 470-482 as follows.

“The small number of participants in the present study who were from a single demographic background (i.e., 30 younger Japanese adults) limit the generalizability of its findings. Future research can address these limitations by including larger sample of gender-diverse individuals from various cultural backgrounds and age range (i.e., children, adolescents, and older individuals in addition to younger adults only). Such diversified studies will allow for more informed conclusions via broader examination of the potential effect of age, culture, and gender on present findings.

Another venue in which the future research can further the present findings is through adaptation of different types of robots for touch interaction to verify how such variety may affect the perception of physical interaction by human subjects. For instance, these studies may consider the change in degree of trust, likeability, etc. by human subjects as a function of varying level of human-likeness of such physically interacting agents. In the same vein, they may also compare the human-likeness versus more animal-like look-and-feel to verify how such a change in appearance could help in addressing human subjects' affective stance toward robots.”

Author Response File: Author Response.pdf

Reviewer 3 Report

The proposed work aims at investigating the humans psychological and social response to robot autonomy. The authors conducted an experiment in which a robot-arm touched the left arm of different participants in different conditions. Considering the ongoing advancements in terms of social and industrial robotics, this research is very interesting and topical. Following, some minor revisions are proposed.

• From line 93: it is not clear how the robot can touch the participants exactly in the same body part and with the same force/pressure regardless of the different anthropocentric features of the participants. Is there a motion tracking based on a vision system? Or was the contact handled using fixed references for the robot's trajectories and people's postures? Please clarify;
• Section 2.3.2: please describe why the authors decided to use the saliva analysis for their evaluation. Is it the best solution for that kind of experiment? Or are there other relevant possibilities? Please clarify;
• Section 4: this study refers to the social interaction between humans and robots. Nevertheless, the experiment involves an industrial robot. The authors should argue how the achieved results can (hypothetically) be affected by using a different kind of robot arm (i.e. an arm characterized by a greater anthropomorphism such as the one from a social robot).
• Captions of Fig.1/3/4/5/6: the captions are very extensive and often redundant with what is already described in the texts. It is recommended to move the most important information into the text (if not already present) and to minimize the description of the images;
• In general, there are several repetitions on the description of the experiment between different sections of the article;

Other suggestions:

• Fig.1: check the spelling of “Salive”;
• Fig.2/3/4/6: font type and dimension are not coherent with the texts;
• Fig.A1: the picture is in the middle of the reference section. Please check;
• Line 50: there is an error in the reference format;
• Line 189: the recalled “section” misses the number;
• Line 278 and 280: check the format and the spacing of the equations;
• Line 285+286 and 338+339: check how the new line is started;
• Reference nr. 49 and nr. 50 are the same. Please check if there are other redundancies.

Author Response

First and foremost, we are thankful for the reviewer’s time and kind consideration to review the present manuscript. Reviewer’s comments substantially improved the quality of the present study and its presentation.

In what follows, point-by-point responses to reviewer’s comments and concerns are provided.

Sincerely,

Reviewer 3

Reviewer’s Comment: From line 93: it is not clear how the robot can touch the participants exactly in the same body part and with the same force/pressure regardless of the different anthropocentric features of the participants. Is there a motion tracking based on a vision system? Or was the contact handled using fixed references for the robot's trajectories and people's postures? Please clarify;

Author’s Response: In the present study, we used the same robot's touch-behaviour that followed fixed references for the robot-arm trajectories and people's postures. To further clarify this point and also discuss possible scenarios for study of its effect and improvement, we added the following paragraph to Section 5. Concluding Remarks, Lines 483-487, in the current version of manuscript.

“Another possibility to extend the present findings is through introduction of various robot's behavioural paradigms. Specifically, the present study used the same robot's touch-behaviour that followed fixed references for the robot-arm trajectories and people's postures. In this regard, it becomes more interesting to verify whether the robot ability to adjust its touch as per individuals' pose and posture can affect their attitude toward robot.”

Reviewer’s Comment: Section 2.3.2: please describe why the authors decided to use the saliva analysis for their evaluation. Is it the best solution for that kind of experiment? Or are there other relevant possibilities? Please clarify;

Author’s Response: Our choice of salivary cortisol was motivated by a recent study by Turner-Cobb et al. [36] who showed its utility for evaluating individuals’ stress reactivity and adaptation during their interaction with robots. We included this explanation in Section 2.3.2 Saliva Sample, lines 125-128, in current version of the manuscript.

 “The use of salivary cortisol to verify if different robot-physical-contact scenarios could induce different degree of stress response in human subjects was motivated by previous studies such as Turner-Cobb et al. [36] who showed its utility for evaluating individuals’ stress reactivity and adaptation during their (social) interaction with robots.”

Reviewer’s Comment: Section 4: this study refers to the social interaction between humans and robots. Nevertheless, the experiment involves an industrial robot. The authors should argue how the achieved results can (hypothetically) be affected by using a different kind of robot arm (i.e. an arm characterized by a greater anthropomorphism such as the one from a social robot).

Author’s Response: We thank the reviewer for this important note that we missed in the first version of the manuscript. We addressed it in the newly added Section 5. Concluding Remarks, lines 476-482 as follows.

“Another venue in which the future research can further the present findings is through adaptation of different types of robots for touch interaction to verify how such variety may affect the perception of physical interaction by human subjects. For instance, these studies may consider the change in degree of trust, likeability, etc. by human subjects as a function of varying level of human-likeness of such physically interacting agents. In the same vein, they may also compare the human-likeness versus more animal-like look-and-feel to verify how such a change in appearance could help in addressing human subjects' affective stance toward robots.”

Reviewer’s Comment: Captions of Fig.1/3/4/5/6: the captions are very extensive and often redundant with what is already described in the texts. It is recommended to move the most important information into the text (if not already present) and to minimize the description of the images;

Author’s Response: Figures 1, 3, 4, 5, and 6 captions are reduced. We also realized that (as noted by the reviewer) all information that have been removed were already explained within the manuscript’s text. Therefore, no additional information was added for these figures within manuscript’s text.

Reviewer’s Comment: In general, there are several repetitions on the description of the experiment between different sections of the article;

Author’s Response: We read through the manuscript carefully and removed/reduced information that appeared to be repeated and/or redundant.

Reviewer’s Comment: Fig.1: check the spelling of “Salive”;

Author’s Response: “Salive” is corrected in Figure 1.

Reviewer’s Comment: Fig.2/3/4/6: font type and dimension are not coherent with the texts;

Author’s Response: All figures have been checked and their size, font type and dimension are adjusted accordingly. Please kindly let us know if further modifications are required.

Reviewer’s Comment: Fig.A1: the picture is in the middle of the reference section. Please check;

Author’s Response: We moved Figure A1 out of Reference Section and made sure that Reference Section started following the end of last Appendix Section i.e., Appendix C.

Reviewer’s Comment: Line 50: there is an error in the reference format;

Author’s Response: Reference format “(Ishowo-Oloko et al. [25, pages 519-520])” is corrected. It reads “(Ishowo-Oloko et al. [25] (p. 519-520))” in the current version of the manuscript.

Reviewer’s Comment: Line 278 and 280: check the format and the spacing of the equations;

Author’s Response: Format and spacing of these equations are fixed (lines 282-283, in the current version of manuscript).

Reviewer’s Comment: Line 285+286 and 338+339: check how the new line is started;

Author’s Response: New lines are corrected (lines 288-289 and line 341, in the current version of manuscript).

Reviewer’s Comment: Reference nr. 49 and nr. 50 are the same. Please check if there are other redundancies.

Author’s Response: Duplicate reference number 50 is removed.

Author Response File: Author Response.pdf