Determining intensity of a biological response to a presentation

1. A method to modify a presentation, the method comprising:

accessing, via a processor, first galvanic skin response (GSR) data obtained from a subject, the first GSR data obtained by a GSR sensor coupled to the subject while the subject is exposed to a presentation during a period of time, the presentation presented to the subject via a presentation device, the first GSR data including a plurality of trough-to-peak instances occurring during the period of time;

generating, by executing an instruction with the processor, a first GSR intensity profile by:

assigning trough-to-peak scores to corresponding ones of the trough-to-peak instances;

defining a plurality of time windows in the period of time, each of the time windows commencing a first time period after a preceding time window commences and each of the time windows having a duration of a second time period, the second time period greater than the first time period; and

assigning window scores to corresponding ones of the time windows based on the trough-to-peak scores of the trough-to-peak instances occurring within the corresponding time windows to generate the first GSR intensity profile;

identifying, by executing an instruction with the processor, an element of the presentation corresponding to a first level of GSR satisfying a threshold based on the first GSR intensity profile;

modifying, by executing an instruction with the processor, the identified element of the presentation to create a modified presentation;

generating, by executing an instruction with the processor, a second GSR intensity profile based on second GSR data obtained from the subject, the second GSR data obtained by the GSR sensor while the subject is exposed to the modified presentation;

determining, by executing an instruction with the processor, a second level of GSR corresponding to at least a portion of the modified presentation based on the second GSR intensity profile; and

determining, by executing an instruction with the processor, whether the second level of GSR no longer satisfies the threshold.

2. The method of claim 1 , wherein the trough-to-peak instances include corresponding troughs and peaks, and the processor generates the first GSR intensity profile by assigning the trough-to-peak scores to the troughs of the corresponding trough-to-peak instances.

3. The method of claim 1 , further including identifying a highest trough-to-peak score within the corresponding time windows, the assigning of the window scores to the time windows including selecting the highest trough-to-peak score occurring within the corresponding time windows as the corresponding window scores.

4. The method of claim 1 , wherein the time windows have corresponding start times and end times, and the assigning of the window scores to the time windows including assigning the window scores to the start times of the corresponding time windows.

5. The method of claim 1 , wherein the subject is a first subject, the method further including:

averaging the first GSR intensity profile of the first subject with a GSR intensity profile of a second subject to create an aggregated GSR intensity profile;

normalizing the aggregated GSR intensity profile; and

identifying the element of the presentation based on the normalized aggregated GSR intensity profile.

6. The method of claim 1 , further including:

identifying trough-to-peak instances in baseline GSR data obtained from the subject during a baseline test;

dividing the identified trough-to-peak instances into ranges; and

respectively assigning baseline values to the ranges, the trough-to-peak scores of the trough-to-peak instances based on corresponding ones of the baseline values.

7. An apparatus to modify stimulus material, the apparatus comprising:

a galvanic skin response (GSR) sensor to gather first GSR data from a subject during a period of time while the subject is exposed to stimulus material via a presentation device; and

a processor communicatively coupled to the presentation device and the GSR sensor, the processor including:

a trough-to-peak scorer to assign trough-to-peak scores to corresponding trough-to-peak instances in the first GSR data occurring during the period of time;

a window generator to define a plurality of time windows in the period of time, each of the time windows commencing a first time period after a preceding time window commences and each of the time windows having a duration of a second time period, the second time period greater than the first time period;

a window scorer to assign window scores to corresponding ones of the time windows based on the trough-to-peaks scores of the trough-to-peak instances occurring within the corresponding time windows;

an intensity profile generator to generate a first GSR intensity profile based on the window scores;

an effectiveness determiner to identify an element of the stimulus material corresponding to a first level of GSR satisfying a threshold based on the first GSR intensity profile; and

a presentation modifier to modify the identified element of the stimulus material to create a modified stimulus material, wherein,

the intensity profile generator is to generate a second GSR intensity profile based on second GSR data obtained from the subject, the second GSR data obtained by the GSR sensor while the subject is exposed to the modified stimulus material, and

the effectiveness determiner is to determine a second level of GSR corresponding to at least a portion of the modified stimulus material based on the second GSR intensity profile, and determine whether the second level of GSR no longer satisfies the threshold.

8. The apparatus of claim 7 , wherein the trough-to-peak instances include corresponding troughs and peaks, and the window scorer is to assign the trough-to-peak scores to the troughs of the corresponding trough-to-peak instances.

9. The apparatus of claim 7 , wherein the window scorer is to assign the window scores to the corresponding time windows by selecting a highest trough-to-peak score occurring within the corresponding time windows as the corresponding window scores.

10. The apparatus of claim 7 , wherein the time windows have corresponding start times and end times, and the window scorer is to assign the window scores to the time windows by assigning the window scores to the start times of the corresponding time windows.

11. The apparatus of claim 7 , wherein the first GSR intensity profile is a graph of the window scores over time.

12. The apparatus of claim 7 , wherein the subject is a first subject, and the intensity profile generator is to:

average the first GSR intensity profile of the first subject with a GSR intensity profile of a second subject to create an aggregated GSR intensity profile; and

normalize the aggregated GSR intensity profile, the identification of the element based on the normalized aggregated GSR intensity profile.

13. The apparatus of claim 7 , wherein the presentation modifier is to remove the identified element from the stimulus material to create the modified stimulus material.

14. The apparatus of claim 7 , wherein the presentation modifier is to repeat the identified element in the stimulus material to create the modified stimulus material.

15. The apparatus of claim 7 , wherein the presentation modifier is to replace the identified element with an alternative element to create the modified stimulus material.

16. A tangible machine readable storage medium comprising instructions that, when executed, cause a machine to at least:

assign trough-to-peak scores to corresponding trough-to-peak instances in first galvanic skin response (GSR) data, the first GSR data obtained from a subject by a GSR sensor coupled to the subject while the subject is exposed to a presentation during a period of time, the presentation presented to the subject via a presentation device;

define a plurality of time windows in the period of time, each of the time windows commencing a first time period after a preceding time window commences and each of the time windows having a duration of a second time period, the second time period greater than the first time period;

generate a first GSR intensity profile by assigning window scores to corresponding ones of the time windows based on the trough-to-peaks scores of the trough-to-peak instances occurring within the corresponding time windows;

identify an element of the presentation corresponding to a first level of GSR, based on the first GSR intensity profile, that does not satisfy a threshold;

modify the identified element of the presentation to create a modified presentation;

generate a second GSR intensity profile based on second GSR data obtained from the subject, the second GSR data obtained by the GSR sensor while the subject is exposed to the modified presentation;

determine a second level of GSR corresponding to at least a portion of the modified presentation based on the second GSR intensity profile; and

determine whether the second level of GSR satisfies the threshold.

17. The tangible machine readable storage medium of claim 16 , wherein the instructions, when executed, further cause the machine to:

identify trough-to-peak instances in baseline GSR data obtained from the subject during a baseline test;

divide the identified trough-to-peak instances into ranges; and

respectively assign baseline values to the ranges, the trough-to-peak scores of the trough-to-peak instances based on the corresponding ones of the baseline values.