Adults Do Not Appropriately Consider Mass Cues of Object Brightness and Pitch Sound to Judge Outcomes of Collision Events

Round 1

Reviewer 1 Report

The manuscript reports the results of two experiments in which subjects judged whether a "collision" between two objects produced a "likely" or "unlikely" outcome.  Subjects' expectations about the collision were influenced by the darkness of the moving object in one experiment, and the by the sound produced by the simulated collision in the other.  The authors' hypotheses about the effect of the sensory cues on expectation did not receive unambiguous support.  Interesting questions could be asked about the interactions between conflicting sensory information.  In this case the experiments are part of a planned study of infants, a potentially rich area of study for the future. The amount of data collected was surprisingly small - one trial for each of four conditions per subject.  The amount of text devoted to discussion and interpretation of the meager results is out of proportion to the size of the experiments and the consistency of the outcomes.

Specific comments:

line 45-46:  One of the cited papers probably mentions that small stiff objects naturally vibrate at higher frequencies than objects with greater mass (bells and organ pipes are familiar examples).  Would it be useful to mention that there is a physical basis for expecting an association between size and pitch?  I think so, but it's not an essential point so I'll leave it to the authors.

line 127: The Macbook is said to have a 13-inch screen.  On line 171, it's described as 34 cm.  It's the same screen obviously, but use consistent units (or mention it only once).

line 160:  It's not obvious what is meant by "average auditory frequency".  A statement that mentioned bandwidth would be more informative.  The same comment applies to lines 263-264.

line 205-211 and Fig 2:  The ratings for the two two dark-ball conditions were not significantly different, and the figure makes it clear that there extensive overlap in the ratings.  The attempt to explain the non-existent difference is not convincing. 

line 282:  Include this statement in the description of the procedure for Exp. 1.

Author Response

Reviewer 1:

Comments and Suggestions for Authors

The manuscript reports the results of two experiments in which subjects judged whether a "collision" between two objects produced a "likely" or "unlikely" outcome.  Subjects' expectations about the collision were influenced by the darkness of the moving object in one experiment, and the by the sound produced by the simulated collision in the other.  The authors' hypotheses about the effect of the sensory cues on expectation did not receive unambiguous support.

 Interesting questions could be asked about the interactions between conflicting sensory information.  In this case the experiments are part of a planned study of infants, a potentially rich area of study for the future. The amount of data collected was surprisingly small - one trial for each of four conditions per subject.  The amount of text devoted to discussion and interpretation of the meager results is out of proportion to the size of the experiments and the consistency of the outcomes.

We thank R1 for their comment, we have shortened our discussion of findings sections accordingly, and shortened our general discussion section to include an extended version of the discussion of findings section.

 

Specific comments:

line 45-46:  One of the cited papers probably mentions that small stiff objects naturally vibrate at higher frequencies than objects with greater mass (bells and organ pipes are familiar examples).  Would it be useful to mention that there is a physical basis for expecting an association between size and pitch?  I think so, but it's not an essential point so I'll leave it to the authors.

We thank R1 for their comment and believe this is a useful addition to line 45-46. Therefore, we have included the following text : “Similarly, associations between pitch and weight may exist due to a physical basis because animals that produce a low pitch sound are usually bigger in size, thus heavier in weight [1]”

 

line 127: The Macbook is said to have a 13-inch screen.  On line 171, it's described as 34 cm.  It's the same screen obviously but use consistent units (or mention it only once).

We thank R1 for their comment, we have now corrected all screen measurements in-line with international system (SI) of units, so have used centimetres (cm) (i.e. ‘34 cm’).

 

line 160:  It's not obvious what is meant by "average auditory frequency".  A statement that mentioned bandwidth would be more informative.  The same comment applies to lines 263-264.

We thank R1 for their comment, we have now re-analysed the sound clips. We have included the sound at the time of the ball hitting the cube (impact). The method section of experiment 1 now reads: “The stimulus had a duration of .3 s, an acoustic amplitude of 50 - 58 dB (range) and an auditory frequency of 32 - 851 Hz (range). The impact sound (i.e. when the ball hit the cube) was 851 Hz and 58 dB. “ The method section of experiment 2 now reads: “Additionally, a .3 s sound during the collision was pitched high or low for the test events. The low-pitch sound had an acoustic amplitude of 50 - 56 dB (range) and an auditory frequency of 29 - 633 Hz (range). The impact sound (i.e. when the ball hit the cube) was 633 Hz and 56 dB. The high-pitch sound had an acoustic amplitude of 50 -60 dB (range) and an auditory frequency of 43 -1011 Hz (range). The impact sound (i.e. when the ball hit the cube) was 1011 Hz and 60 dB.”

 

line 205-211 and Fig 2:  The ratings for the two dark-ball conditions were not significantly different, and the figure makes it clear that there extensive overlap in the ratings.  The attempt to explain the non-existent difference is not convincing.

We thank R1 for this comment, and apologise for the long response to this suggestion, but respectfully disagree with the practice of implementing an arbitrary threshold probability and accepting 'significant' or otherwise. We (authors of this paper) are being informed by statisticians such as Hurlbert et al. and the American Statistical Association. An excerpt from the Hulbert article (cited in the manuscript) is here: 'we propose that in research articles all use of the phrase “statistically significant” and closely related terms (“nonsignificant,” “significant at p = 0.xxx,” “marginally significant,” etc.) be disallowed on the solid grounds long existing in the literature. Just present the p-values without labeling or categorizing them. Every professional statistician, every scientist who uses statistics, and every statistics instructor is in a position to help build momentum for this improvement and proscribe “statistically significant” in those situations where they have individual decision-making authority.'

 

As such, we wish to apply this approach to the present manuscript to future proof our work. We are aware it may be controversial, and some scientists may disapprove. However, if the reader is insistent on implementing a threshold probability level, they can do so if the article presents exact P values (which we have). We have indicated on figure 2 exact P values P, for those readers who adhere to the most commonly used threshold of probability. We have published some articles using this approach previously (https://www.sciencedirect.com/science/article/pii/S0531556520304228?via=ihub; https://www.sciencedirect.com/science/article/pii/S0531556520304228?via=ihub; https://link.springer.com/article/10.1007/s00421-021-04635-2), so believe it acceptable in the literature.

 

A proposed journal policy has been described by Hurlbert as follows: 'There is now wide agreement among many statisticians who have studied the issue that for reporting of statistical tests yielding p-values it is illogical and inappropriate to dichotomize the p-scale and describe results as “significant” and “nonsignificant.” Authors are strongly discouraged from continuing this never justified practice that originated from confusions in the early history of modern statistics.'

 

A shining light of this approach is given as the Pocock et al (2016) article (https://www.sciencedirect.com/science/article/pii/S0735109716351099?via%3Dihub) where trends are described in crude terms (e.g. 'The 6-month changes in office systolic BP in the RDN (n = 350) and sham control (n = 169) arms were −15.3 ± 23.9 mm Hg and −11.2 ± 26.4 mm Hg, respectively, with large variations in BP, as noted in Figure 1.'). P values, 95% CIs, and effect sizes are given and left for the reader to interpret.

 

Interpretation of the data is within the discussion, where we have considered P, CIs, and effect size. We hope R1 accepts our desire to present data using this philosophy as we appreciate differences in preference exists between scientists.

 

We, of course, agree that on figure 2 there is an overlap of data between the dark test events and the magnitude of effect is small (r=0.39), particularly compared to the difference between bright ball events (r=0.94). Still, there remains significant overlap in the bright ball events data. We believe we are not trying to explain a not-existent difference, but reason the difference in magnitudes.

 

line 282:  Include this statement in the description of the procedure for Exp. 1.

We thank R1 for their comment, we have included following “Participants saw each event once and watched events on a Macbook Air 34 cm screen with headphones on, and verbally assessed the collision events by rating them on a scale from 1 (very unlikely) to 10 (very likely) on how real life they were” for Experiment 1. For Experiment 2, we have reworded this procedure section to read “Other than the sound manipulation, the procedure was the same as in Experiment 1. Participants were divided into following groups and viewed each event once shown on Fig 3 in the following sequence:”

 

Reviewer 2 Report

Abstract

l. 20  the definition of likely events is not clear in the avbstract. "the bright ball likely event (where the bright ball hit an object a short distance)" : “hit” is not correct in this context. Maybe rephrase it as something like "where a moving bright ball displaced a stationary cube over a short distance after colliding with it"

l.23: idem

Introduction

l.33-34, 82-83, and 91-92: too many repetitions of the same text

l.103-104: The present investigation considers an adult audience, not an infant one.

Section 2 Experiment 1 methods

Fig. 1 : This figure suggests that was there also a grey ball involved?

 

Suggestion

Why did the authors not test a combination of both brightness and sound? There may be some interesting nonlinear integration effects.

Author Response

Reviewer 2:

Open Review

Comments and Suggestions for Authors

Abstract

1. 20 the definition of likely events is not clear in the abstract. "the bright ball likely event (where the bright ball hit an object a short distance)" : “hit” is not correct in this context. Maybe rephrase it as something like "where a moving bright ball displaced a stationary cube over a short distance after colliding with it"

l.23: idem

We thank R2 for their comment, we have now replaced “hit an object” with “replaced a stationary object”, and included “after colliding with it” in the Abstract.  A likely event is hopefully more clear now, as “where the bright ball displaced a stationary object a short distance after colliding with it” and “where the dark ball displaced a stationary object a short distance after colliding with it”.

 

Introduction

l.33-34, 82-83, and 91-92: too many repetitions of the same text

We thank R2 for their comment, we have now removed “Adults judge brighter objects and higher pitch sounds to be lighter in weight, and darker objects and lower pitch sounds to be heavier in weight” [1] in line 82-83 and “Taken together, adults judge darker objects and lower pitch sounds to be heavier in weight, and brighter objects and high pitch sounds to be lighter in weight” [1] in line 91-92.

 

l.103-104: The present investigation considers an adult audience, not an infant one.

We thank R2 for their comment, we have now changed it to “designed as a precursor for an infant audience”.

 

Section 2 Experiment 1 methods

Fig. 1: This figure suggests that was there also a grey ball involved?

We thank R2 for this observation, and yes there was a grey ball in the image. However, the grey ball remained stationary and was just a prop. In future studies, they grey ball was used, but not in the present study. we have added “the grey ball in figure 1 remained stationary and was merely a prop.” In line 138.

 

Suggestion

Why did the authors not test a combination of both brightness and sound? There may be some interesting nonlinear integration effects.

We thank R2 for their comment, and we hope to examine this in our future work.

Round 2

Reviewer 1 Report

My comments have been addressed.