Multitasking Effects on Perception and Memory in Older Adults
Round 1
Reviewer 1 Report
This paper is clear and well writen. However, I have some suggestions.
Firslty, you need to clearly present your research data - use tables and describe collected data.
Secondly, in line 283 "The age variable was centered to avoid multicollin- earity issues" - i'm not sure what does this mean? - Can you provide some more explanation to support this statement. In case you have y = a +bx1 + cx2 + dx3 - when independent variales for example (x1 and x2) are highly correlated results will be folsely insignificant.
Thirdly, not only the data but the results should be presentes more clearly (in tables).
Eventualy, results needs to be discussed more extensively in context of similar and related research papers.
Author Response
We sincerely thank the Reviewer for their thorough review of our manuscript and for the excellent suggestions that we received. We have made a concerted effort to adequately respond to each suggestion received from the Reviewer. We firmly believe that the Reviewer’s comments and suggestions have significantly improved this manuscript. We do hope that you and the Reviewer find this manuscript acceptable for publication in Vision.
Comments from Reviewer 1
This paper is clear and well written. However, I have some suggestions.
Firstly, you need to clearly present your research data - use tables and describe collected data.
Answer
We have included descriptive tables for the variables in the manuscript.
Secondly, in line 283 "The age variable was centered to avoid multicollinearity issues" - I'm not sure what does this mean? - Can you provide some more explanation to support this statement. In case you have y = a +bx1 + cx2 + dx3 - when independent variables for example (x1 and x2) are highly correlated results will be falsely insignificant.
Answer
We thank the Reviewer for pointing out that the sentence was inappropriate. The mixed models here include only one continuous variable and thus there are no multicollinearity issues. We repeated the analysis with the raw age variable without centering or rescaling. As expected, the results overlap with those presented in the first submission. In the revised version of the manuscript, the sentence has been removed.
Thirdly, not only the data but the results should be presented more clearly (in tables).
Answer
We have included summarizing tables for the main results from the Analysis of deviance with the Type II Wald chi-square.
Eventually, results need to be discussed more extensively in the context of similar and related research papers.
Answer
We have extended the discussion section and better linked our study with additional, relevant papers in the field. The new entries were highlighted in yellow in the submission.
Reviewer 2 Report
Thank you for asking me to review this very exciting manuscript on cognitive load during multitasking.
Some minor points:
Please be consistent and use either US or UK English spelling.
With respect to the participants, were neurological, psychiatric, or addiction disorders entirely exclusionary, or only if the conditions were not stable? Please clarify in the manuscript.
Please create a flow chart, showing how many participants were recruited, how many enrolled, how many were turned away, how many were removed from the analysis (and for what reason), etc.
For the subject demographics, please also include participant education level, and include in the results how education level affecting the findings, if at all.
For Figure 3, please change the legend to use different markers. One suggestion could be squares for "high load", circles for "low load", and triangles for "no load". Same goes for Figure 4 and Figure 1A in the appendix. This is purely for ease of reading for readers who print articles in black and white.
Overall, this is an excellent manuscript, and should be publishable once these corrections are made.
Author Response
We sincerely thank the Reviewer for their thorough review of our manuscript and for the excellent suggestions that we received. We have made a concerted effort to adequately respond to each suggestion received from the Reviewer. We firmly believe that the Reviewer’s comments and suggestions have significantly improved this manuscript. We do hope that you and the Reviewer find this manuscript acceptable for publication in Vision.
Comments from Reviewer 2
Thank you for asking me to review this very exciting manuscript on cognitive load during multitasking.
Some minor points:
Please be consistent and use either US or UK English spelling.
Answer
We thank the Reviewer for this comment, we have modified the text so that it is more consistent linguistically.
With respect to the participants, were neurological, psychiatric, or addiction disorders entirely exclusionary, or only if the conditions were not stable? Please clarify in the manuscript.
Answer
The presence of neurological or psychiatric disorders or history (past and present) of addiction disorders was entirely exclusionary. We rephrased the sentence as follows: “Inclusion criteria were normal or corrected-to-normal vision and hearing. Exclusion criteria were the presence of psychiatric disorders, history of addiction disorders (alcohol or drug abuse), and presence of severe neurological disorders (MCI or dementia).”
Please create a flow chart, showing how many participants were recruited, how many enrolled, how many were turned away, how many were removed from the analysis (and for what reason), etc.
Answer
We have included a flow chart summarizing the procedure for including and recruiting participants. It contains all the numbers requested by the Reviewer.
For the subject demographics, please also include participant education level, and include in the results how education level affecting the findings, if at all.
Answer
Thank you for making us reflect on the relevance of education in this context. Given the protective effect that education has on cognitive decline (Sidenkova, 2020), it is important to consider this factor as well. As previously reported by Nucci et al. in 2012, in the Italian population, schooling and age are expected to correlate with an R2 higher than .40 [37]. Despite this strong correlation, education could have an independent effect from that of age and potentially mitigate its effects. Therefore, we thought it was important to report the effects of education on the dual memory task. Specifically, we tested whether education has a protective effect against secondary task interference regardless of age. To do this, from the raw score of years of schooling, we calculated an index for education using the method proposed by Nucci (2012). This method predicts that the residuals of the regression years of schooling * age are then normalized with a mean of 100 and a standard deviation of 15. The results show that, although high levels of education correspond to high levels of performance on the memory task, there is no interaction with cognitive load. This means that education does not have an influence on cost. The sections of the introduction, method, results, and conclusions have been updated to include this interesting result.
For Figure 3, please change the legend to use different markers. One suggestion could be squares for "high load", circles for "low load", and triangles for "no load". Same goes for Figure 4 and Figure 1A in the appendix. This is purely for ease of reading for readers who print articles in black and white.
Answer
We have changed the thickness of lines in Figure 4, and added different markers to Figures 3, and 1A so that they can be easily distinguished when printed in black and white. We also moved the legend of Figure 1A to a more readable position.
Round 2
Reviewer 1 Report
I support this paper in the form as is, so my recommendation would be to publish.
Reviewer 2 Report
Thank you for addressing my comments. The paper is suitable for publication.
