Characteristics of visual perception of patients’ faces and the formation of “observation” in the process of training cosmetologists

Yarovaya Natalia Pavlovna ORCID: 0000-0001-7256-1550 Postgraduate student, Department of General and Clinical Psychology, St. Petersburg State Medical University named after Academician Pavlov 196105, Russia, Saint Petersburg, Yakovlevsky str., 7-1 dr.yarovaya@gmail.com

Introduction

Professional experience includes accumulated knowledge and skills acquired during training and further work in a specific professional field. This experience allows specialists to process information faster and more efficiently and make more accurate decisions ^[5].

One of the components of professional experience is a lot of observation. The ability to perceive visual information quickly and accurately within a certain area of professional activity, as well as the result of systematic training, professional development and long-term practice ^[6,14].

In addition to the ability to quickly isolate significant information from the visual stream, important characteristics of the overlooked are ^{[7, 14]}:

1. Accuracy. The ability to make accurate and reliable conclusions based on visual data includes a lot of observation.

2. Identifying patterns. The lack of visibility helps specialists to detect visual patterns, connections and trends that might have gone unnoticed by less experienced observers.

3. The ability to differentiate. Thanks to watching, professionals not only identify different elements in complex visual scenes, but also determine how they interact with each other.

4. Strategic approach. Viewing includes various strategies for effective analysis of visual data. With their help, the specialist quickly determines which details to focus on first and what steps to take to obtain the necessary information.

5. Adaptation to the context. Watching helps you adapt to different contexts and conditions, with completely different visual information.

6. The ability to self-esteem. The review includes processes for analyzing and evaluating one's own perception and decision-making processes, which leads to a reduction in the risk of errors.

The assessment of viewing is a difficult task, since it depends on many factors and must be adapted to a specific professional field and research goals ^[5]. However, there are various methods and tools that can be used to measure the level of neglect in professional activities, for example:

1. Assessment through tasks and scenarios. It involves providing specialists with various tasks, scenarios and visual materials, and then evaluating their ability to correctly and quickly highlight key information.

2. Expert assessment. Experts in a specific field can evaluate the participants' visibility by observing their performance and ability to analyze visual information.

3. Tests and questionnaires. Professional tests and questionnaires can be developed to assess the ability to analyze visual information.

4. Eye movement tracking (eye tracking). An objective method for studying human visual perception, which allows you to identify what and in what sequence the attention of a specialist was paid to when analyzing an image or video ^[8].

Most of the research works use the eyetracking method to analyze the relationship between professional experience and characteristics of oculomotor activity ^[2,11,15]. For example, in our previous work, we showed that experienced doctors have formed optimal scanning schemes, which allows us to effectively distribute attention and quickly and accurately identify key diagnostic signs in images among a variety of minor details ^[1].

For experienced cosmetologists, diagnosis can be to some extent an unconscious process based on automatic recognition of visual images, which involves quickly correlating the clinical picture with knowledge stored in long-term memory. Thanks to their observation, they develop more effective search strategies that allow them to quickly direct attention to diagnostically significant areas of the image. Such specialists are able to perceive the entire image of the patient, which allows them to more effectively direct their attention to diagnostically significant signs, reducing the overall length of the image scan, compared with young specialists. Thus, it can be concluded that experienced doctors have an effective visual search, which is due to their observation and experience.

The objective of this work is to analyze changes in oculomotor patterns after completing the author's training program for cosmetologists aimed at versatile aesthetic analysis of the face, building individual therapy protocols in aesthetic medicine. The study also aimed to assess the possibility of the formation of a lack of awareness through specialized training of doctors.

Research methods

The study involved 30 cosmetologists with work experience from 0 to 24 years, the average work experience was 9.1± 7.5 years. The average age of the participants was 33.4±7.8 years; among them 2 men and 28 women.

The study was conducted in two stages. Both at the pre- and post-training stages, cosmetologists were presented with 15 faces of patients with various cosmetological and dermatological problems on a computer screen. The stimuli were randomly selected from a database of photographs taken by the author of this work during a previous study ^[1].

The study participants were tasked with detecting signs of dermatological and cosmetic problems in patients. In the course of this, eye movements were recorded using the Neuroburo software and hardware complex ^[3].

The processing of the coordinates of the gaze position was carried out using the algorithm of the I-VT family (the Velocity-Threshold Identification), which consists in classifying eye movements based on determining the saccade velocity threshold ^[9]. The speed threshold used was 70°/s. To increase the accuracy of the data obtained, the following filters were used: filling in gaps, selecting a data source, noise suppression, combining adjacent fixations, and removing short fixations. This processing was carried out using the Neuroburo software.

Further statistical processing was performed in the Statistica software using descriptive statistics, the Shapiro-Wilk test and the Wilcoxon T-test.

The results of the study

In the course of this study, we analyzed such characteristics of gaze fixations as: the total number of visual fixations, the duration of the first fixation, and the average duration of fixations. We also evaluated such a parameter of visual saccades as the average amplitude. Additionally, two integrative indicators were analyzed, namely: the total viewing time and the total length of the visual scanning path. Table 1 shows the average values and standard deviations of these parameters.

According to the Shapiro-Wilk criterion, the distribution differs from the normal one. A nonparametric criterion, namely the Wilcoxon T-test, was used to compare the parameters of oculomotor activity before and after training.

Table 1. Values of oculomotor activity parameters before and after training

Figures 1-5 show a box plot for each parameter of oculomotor activity, showing the average value, upper and lower quartiles, as well as the range without outliers.

Let's consider statistically significant changes in the parameters of oculomotor activity after training. In general, cosmetologists began to take less time to analyze each face (p<0.01). This was achieved by reducing the number of visual fixations (p<0.005) and increasing the amplitude of saccades (p<0.005) (Fig.1,2,3).

The reduction of the total length of the scanning path (p<0.01) allows us to make an assumption about the structuring of the analysis scheme based on the use of key points (Fig.4). A similar change in oculomotor activity patterns was observed with an increase in the professional experience of cosmetologists both in our previous study ^[2] and in studies of specialists from other fields of medicine ^{[11, 15]}, as well as chess players ^[13] and musicians ^[4].

There were no statistically significant changes in the average duration of fixations (Fig.5).

Figure 1. Total viewing time of stimuli before and after training.

Figure 2. The total number of fixations on stimuli before and after training.

Figure 3. The average amplitude of saccades on stimuli before and after training.

Figure 4. The total length of the stimulus scanning path before and after training.

Figure 5. The average duration of fixation on stimuli before and after training.

Figures 6 and 7 show the eye movement maps before and after the training of cosmetologists. It can be noted that cosmetologists began to require fewer visual fixations for facial analysis, and the total length of the scanning path of the stimulus image was reduced.

Figure 6 – The path of scanning the stimulus image before (a) and after training (b)

Discussion of the results:

In a comparative analysis of the results obtained before and after the author's training program, cosmetologists:

· The number of visual fixations has decreased. This indicates that they began to more accurately and quickly identify important characteristics on the faces of patients, ignoring irrelevant visual information.

· The amplitude of the visual saccades has increased, indicating wider and more effective eye movements during the analysis process. This allows you to quickly switch between different areas of the face and discover important details. Increasing the amplitude of saccades can be especially useful in the analysis of symmetry, which is an important aspect of cosmetological diagnostics. An increase in the amplitude of saccades also contributes to a more holistic perception of the face for further detailed diagnosis.

· The total length of the scanning path has been reduced, which also indicates a more optimized perception strategy. This allows us to conclude about a more systematic and directed approach of the doctor to the analysis of the diagnostic image.

Conclusions:

The results obtained suggest that during the training process, doctors have improved such an important characteristic of perception as integrity. The development of the ability to perceive holistically can help a specialist to see a wide context and the interrelationships between details, which can be useful in diagnostic analysis and understanding of the main functional problems and impaired structures ^[10,12]. The ability to see a face as an integral object, in the totality of its problem areas, helps to identify cause-and-effect relationships in the occurrence of cosmetological and dermatological problems, to prioritize when choosing a treatment strategy. In turn, the integrity and selectivity of perception are important conditions for the development of observation among cosmetologists, this allows the specialist to better understand exactly what to look for, and which aspects are important for determining effective treatment.

Thus, during professional training, specialists develop holistic perception skills, which allows them to quickly and effectively assess the scale and specifics of cosmetic problems, better understand complaints and expectations of patients. This generalized knowledge and understanding become the basis of observation as a professionally important quality of a cosmetologist.