A Multi-modal Method for Real-Time Assessment during Web Browsing

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A. Participants

Up to 60 participants will be recruited in public schools in Milan. The number of participants (sample size) was calculated in order to have an effect size sufficient to prove the effect of the training, reducing type II (false negative) statistical errors. In order to reduce type I errors (false positive), a test threshold of 0.05 will be used. In order to be included in the study, individuals will have to meet the following criteria: (1) age between 18 and 35 years old; (2) no major medical disorders (heart disease or high blood pressure, neurological disorders, epilepsy); (3) no left-handed, they will be all right-handed; (4) no presence of pharmacotherapy that might interfere with the measured data (psychoactive drugs, anti-hypertensive, anti-depressants); (5) no significant visual impairment (all with normal or correctedto-normal visual acuity).

B. Measurements

1) Neuropsychological evaluation

To measure attention, the following tests will be administered:

• Raven’s progressive matrices, a nonverbal test group used in measuring abstract reasoning and regarded as a non-verbal estimate of fluid intelligence [22];

• Digit Span, in WAIS-IV [23].

2) Web users experience In order to study the browsing experience and the emotional involvement of the participants, a multi-method approach (i.e,; focused on different aspects of the experience from the user) will be implemented. Specifically:

Psychometric Assessment: a battery of psychometric questionnaires will be administered to each participant at the beginning of the experiment and after each experimental condition: (1) State-Trait Anxiety Inventory Form (STAI-Y) [24]; (2) Visual Analogue Scale for Subjective Feelings of Anxiety (VAS-A); (3) System Usability Scale (SUS); (4) Net Promoter Score (NPS); (5) The Geneva Emotion Wheel (GEW); (6) ah hoc design questionair.

Observational-behavioral assessment: the verbal and nonverbal behavior of the participants will be recorded during the experiments. In particular: (1) analysis of verbal behavior: all verbal communications will be recorded and analyzed through specific coding grids; (2) analysis of nonverbal behavior: nonverbal behavior will be video recorded and analyzed in all its main components (e.g., facial expressions, movements in space).

Psychophysiological assessment: the following psychophysiological data will be recorded at the beginning and during the experimental session: (1) eye tracking data; (2) brain activity, assessed through an electroencephalogram (EEG).

C. Stimulus

The stimulus will be composing by an on-line article selected in the lanazione.it website. Article speaks of the flood in Florence in 1966. It ‘was chosen an article about a historical event since it is not affected by the passage of time and can be considered still relevant, in line with what has been said in other reading tests and understanding [25] [26]. For this stimulus was built a 15 questions test understanding, built on the basis of the classification given other reading and comprehension tests and guides for comprehension [25] [27]. In line with these others test, it is necessary that the participant achieve a percentile score higher than or equal to 50 in the Raven’s Progressive Matrices [25].

D. Experimental Design

A within-subjects design will be used to compare user experience from a pre-condition baseline to the experimental condition. Participants will act as their own controls. Specifically, the study will compose by this experimental task: • Comprehension task: Participants will be asked to read an article selected from the most popular online newspaper in Italy (lanazione.it) and later to answer some questions about the understanding of the content.

Before starting the experiment each participant will be provided with written information about the study and will be invited to give written consent for the inclusion. Then, the neuropsychological battery of tests described above will be administered in order to verify the level of attention of each subject.

At the start of the experimental session, participants will seat at a desk in front of a computer monitor. The eye-todisplay distance will be about 0.75 meters. Participants will be connected with EEG for recording their psychophysiological signals (eye tracking and brain data). A baseline measure of these signals will be registered for 3 minutes in rest condition, with eyes opened. Once the physiological baseline will be recorded, the experimental session will start and psychophysiological signals will be recorded until the end of all the tasks.

Then, in order to measure the psychological variations occurring during the different conditions, participants will complete the STAI-Y2, the VAS-A and the GEW, immediately before and after each exposure condition. Participants will complete also the SUS and Net Promoter Score, to assess presence’s level experienced. Before each condition there will be a three-minute baseline assessment during which participants will be asked to stay completely relaxed with open eyes, while their physiological parameters will be recorded.

During the execution of the task, eye tracking and electrocortical activity will be recorded, in order to assess user’s cognitive load in real time.