Name: 시간적 순서 심판의 모델 기반 분석에 의해주의 및 Visual 처리 속도를 측정 (동영상) | JoVE Journal
Uploaded: 2017-01-23T14:00:00.000+00:00
Duration: 13 min
Description: 배우세요 시간적 순서 심판(TOJ)을 사용하여 주의 및 시각 처리 속도를 측정하는 방법을. Bundesen의 시각 주의 이론 기반 모델을 활용해 거의 모든 자극에 적용 가능하며, 베이지안 계층적 분석으로 주의 가중치와 인코딩 속도를 정량화합니다.

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Parts of this work have been supported by the German Research Foundation (DFG) via grants 1515/1-2 and 1515/6-1 to Ingrid Scharlau.

NOTE: Some steps in this protocol can be accomplished using custom software provided (along with installation instructions) at http://groups.upb.de/viat/TVATOJ. In the protocol, this collection of programs and scripts is referred to as &#8220;TVATOJ&#8221;.
1. Selection of Stimulus Material
<ol>
	<li>Select stimuli according to the research question. 
	NOTE: In general, two targets are shown at different locations on the screen. Stimuli that have been used with the present method include, for example, shapes, digits, letters, singletons in pop-out displays, and objects in natural images. The latter three types were used in this protocol. 
	NOTE: Several different stimulus types are included in the TOJ plugin (&#34;psylab_toj_stimulus&#34; provided with TVATOJ) for the experiment builder OpenSesame12.</li>
	<li>When creating new stimulus types, make sure that the properties of interest have to be encoded for the judgment by making them important for the task or select stimuli where the properties of interest are encoded automatically (e.g., singletons in pop-out displays).</li>
</ol>
2. Power Estimation and Planning
<ol>
	<li>Perform a Bayesian power analysis by simulating data sets with the selected model, planned design (SOA distribution and repetitions), sample sizes, and hypothesized parameters. Estimate whether it is likely to reach the research goal (for instance, a certain difference in the parameters). If the power is not sufficient, alter the design by adding or shifting SOAs or repetitions and repeat the analysis.
	<ol>
		<li>To use the provided TVATOJ software, open and edit the script &#34;exp1-power.R&#34;. Follow the comments in the file to adjust it for the specific analysis. For general information on Bayesian power estimation refer to Kruschke13.</li>
	</ol>
	</li>
</ol>
3. Specification or Programming of the Experiment
<ol>
	<li>Use an experiment builder or psychophysical presentation library to implement the experiment.
	<ol>
		<li>To use the OpenSesame TOJ plugin provided in TVATOJ, drag the &#34;psylab_toj_stimulus&#34; plugin into a trial presentation loop. Alternatively, open the &#34;simple-toj.osexp&#34; example experiment in OpenSesame.</li>
		<li>Select the desired stimulus type from the dropdown menu &#34;Stimulus type&#34; in the psylab_toj_stimulus configuration. Follow the instructions in TVATOJ for adding new stimulus types if required.</li>
	</ol>
	</li>
	<li>Specify the trials as described in the following steps.
	<ol>
		<li>For every experimental condition, create trials with the planned SOAs. When using the psylab_toj_stimulus plugin and OpenSesame, add all varied factors as variables to the trial loop (e.g. &#34;SOA&#34;).</li>
		<li>Add rows to the table to realize all factor combinations (e.g., seven SOAs, from -100 to 100 msec, crossed with the experimental conditions &#34;attention&#34; and &#34;neutral&#34;). Adjust the loop&#39;s &#34;Repeat&#34; attribute to create sufficient repetitions (see protocol step 2 for determining the distribution and repetition of SOAs). 
		NOTE: Typically, at most 800 trials can be presented within one hour. If more repetitions are needed, consider splitting the experiment into several sessions. Make sure that the &#34;Order&#34; attribute of the loop is set to &#34;Random&#34; before running the experiment.</li>
		<li>In the psylab_toj_stimulus plugin configuration, add placeholders (e.g. &#34;[SOA]&#34;) for the varied factors in the respective fields. Enter constant values in the fields of factors that are not varied. 
		NOTE: Before running the experiment, make sure that accurate timing is guaranteed. If appropriate timing behavior of newer monitors was not verified, use CRT monitors and synchronize with the vertical retrace signal12.</li>
	</ol>
	</li>
</ol>
4. Experimental Procedure
<ol>
	<li>Welcoming and briefing of the participants
	<ol>
		<li>Welcome the participants and inform them about the general form of the experiment (computer-based perception experiment). Inform the participants about the prospective duration of the experiment. Obtain the participants&#39; informed consent to participate in the experiment.</li>
		<li>Ensure that the participants show normal or corrected-to-normal vision (optimally by conducting short vision tests). Some deficits, such as color blindness, may be tolerable if they do not interfere with the research question for the particular type of stimulus material.</li>
		<li>Provide a quiet booth where the experiment is conducted. Adjust the chair, chin rest, keyboard position, and so on, to ensure optimal viewing and response conditions for the experiment.</li>
		<li>Make the participants aware that the experiment requires attention and mental focus and can be fatiguing. Ask them to take short breaks when required. It is, however, equally important not to perform these simple tasks under strong attentional strain. Tell the participants that it is okay to make some errors.</li>
	</ol>
	</li>
	<li>Instruction and warm-up
	<ol>
		<li>Present onscreen instructions for the task, detailing the presentation sequence and response collection procedure. Inform the participants that the task is to report the order in which the targets arrived, and that this will be difficult in some trials. Ask the participants to report their first impression when they cannot tell the order for certain, and let them guess if they have no such impression at all. 
		NOTE: In the binary TOJs used here, there is no option to indicate the perception of simultaneity. To avoid excessive guessing, do not point out the presence of trials with simultaneously presented targets explicitly. Let these simply be difficult trials with the instructions outlined above.</li>
		<li>To avoid eye movements during the trials, ask participants to fixate a mark which is shown in the center of the screen. Ask them to rest their head on a chin rest.</li>
		<li>Ask the participants to take short breaks if necessary. Let them know when breaks are allowed and when they must be avoided (e.g., during the target presentation and before the response).</li>
		<li>Include a short training in which participants can get used to the task. To this end, present a random subset of the experimental trials (see protocol step 3.2). 
		NOTE: Because the task itself is rather simple, ten to twenty trials are usually sufficient. It can be advantageous to increase the participants&#39; confidence in their performance in this task. This can be done by slowing down the presentation and providing feedback.</li>
		<li>Obtain the participants&#39; confirmation that they have understood the task (let them explain it) and that they have no further questions.</li>
	</ol>
	</li>
	<li>Running the main experiment
	<ol>
		<li>Let the experimental software start with the presentation of the main trials. Leave the booth for the main experiment.</li>
	</ol>
	</li>
</ol>
5. Model-based Analysis of the TOJ Data
<ol>
	<li>Convert the raw data files into counts of &#34;probe first&#34; judgments for every SOA. For instance, run the script &#34;os2toj.py&#34; provided with TVATOJ.</li>
	<li>Run the Bayesian estimation procedure to estimate the main parameters wp and C, the derived ones vp and vr and the differences of the parameters. For this purpose, run the script &#34;run-evaluation.R&#34; after editing it according to the instructions provided in the file.</li>
	<li>When the sampling has finished, the differences of interest for the research questions can be assessed. Examples can be found in the following section.</li>
</ol>

<ol><li>Posner, M. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Orienting+of+attention%5BTitle%5D)+AND+%22Quarterly+Journal+of+Experimental+Psychology%22%5BJournal%5D)">Orienting of attention.</a> Quarterly Journal of Experimental Psychology. 32 (1), 3-25 (1980).</li>
<li>Van der Heijden, A., Wolters, G., Groep, J., Hagenaar, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Single-letter+recognition+accuracy+benefits+from+advance+cuing+of+location%5BTitle%5D)+AND+%22Perception+%26+Psychophysics%22%5BJournal%5D)">Single-letter recognition accuracy benefits from advance cuing of location.</a> Perception & Psychophysics. 42 (5), 503-509 (1987).</li>
<li>Bundesen, C. <a target="_blank" href="https://www.ncbi.nlm.nih.gov/pubmed/2247540">A theory of visual attention.</a> Psychological Review. 97 (4), 523-547 (1990).</li>
<li>Bublak, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Staged+decline+of+visual+processing+capacity+in+mild+cognitive+impairment+and+Alzheimer%27s+disease%5BTitle%5D)+AND+%22Neurobiology+of+Aging%22%5BJournal%5D)">Staged decline of visual processing capacity in mild cognitive impairment and Alzheimer's disease.</a> Neurobiology of Aging. 32 (7), 1219-1230 (2011).</li>
<li>Petersen, A., Kyllingsbæk, S., Bundesen, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Measuring+and+modeling+attentional+dwell+time%5BTitle%5D)+AND+%22Psychonomic+Bulletin+%26+Review%22%5BJournal%5D)">Measuring and modeling attentional dwell time.</a> Psychonomic Bulletin & Review. 19 (6), 1029-1046 (2012).</li>
<li>Vroomen, J., Keetels, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Perception+of+intersensory+synchrony%3A+A+tutorial+review%5BTitle%5D)+AND+%22Attention%2C+Perception%2C+%26+Psychophysics%22%5BJournal%5D)">Perception of intersensory synchrony: A tutorial review.</a> Attention, Perception, & Psychophysics. 72 (4), 871-884 (2010).</li>
<li>Tünnermann, J., Petersen, A., Scharlau, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Does+attention+speed+up+processing%3F+Decreases+and+increases+of+processing+rates+in+visual+prior+entry%5BTitle%5D)+AND+%22Journal+of+Vision%22%5BJournal%5D)">Does attention speed up processing? Decreases and increases of processing rates in visual prior entry.</a> Journal of Vision. 15 (3), 1-27 (2015).</li>
<li>Krüger, A., Tünnermann, J., Scharlau, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Fast+and+conspicuous%3F+Quantifying+salience+with+the+Theory+of+Visual+Attention%5BTitle%5D)+AND+%22Advances+in+Cognitive+Psychology%22%5BJournal%5D)">Fast and conspicuous? Quantifying salience with the Theory of Visual Attention.</a> Advances in Cognitive Psychology. 12 (1), 20(2016).</li>
<li>Bundesen, C., Habekost, T. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aBundesen%2C+C+%22Principles+of+Visual+Attention%3A+Linking+Mind+and+Brain%22">Principles of Visual Attention: Linking Mind and Brain</a>. , Oxford University Press. Oxford, UK. (2008).</li>
<li>Plummer, M. <a target="_blank" href="https://www.r-project.org/conferences/DSC-2003/Drafts/Plummer.pdf">JAGS: A program for analysis of Bayesian graphical models using Gibbs sampling.</a> Proceedings of the 3rd international workshop on distributed statistical computing. , 124-125 (2003).</li>
<li>Kruschke, J. K., Vanpaemel, W. Bayesian estimation in hierarchical models. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aKruschke%2C+JK+%22The+Oxford+Handbook+of+Computational+and+Mathematical+Psychology%22">The Oxford Handbook of Computational and Mathematical Psychology</a>. Busemeyer, J., Townsend, J., Wang, Z. J., Eidels, A. , 279-299 (2015).</li>
<li>Mathôt, S., Schreij, D., Theeuwes, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((OpenSesame%3A+An+open-source%2C+graphical+experiment+builder+for+the+social+sciences%5BTitle%5D)+AND+%22Behavior+Research+Methods%22%5BJournal%5D)">OpenSesame: An open-source, graphical experiment builder for the social sciences.</a> Behavior Research Methods. 44 (2), 314-324 (2012).</li>
<li>Kruschke, J. K. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aKruschke%2C+JK+%22Doing+Bayesian+data+analysis%3A+A+tutorial+with+R%2C+JAGS%2C+and+Stan%22">Doing Bayesian data analysis: A tutorial with R, JAGS, and Stan</a>. , 2nd, Academic Press. Boston, MA. (2015).</li>
<li>Rensink, R. A., O'Regan, J. K., Clark, J. J. <a target="_blank" href="https://www.jstor.org/stable/40063214">To see or not to see: The need for attention to perceive changes in scenes.</a> Psychological Science. 8 (5), 368-373 (1997).</li>
<li>Tünnermann, J., Krüger, N., Mertsching, B., Mustafa, W. <a target="_blank" href="http://link.springer.com/article/10.1007/s12559-015-9329-9">Affordance estimation enhances artificial visual attention: Evidence from a change-blindness study.</a> Cognitive Computation. 7 (5), 525-538 (2015).</li>
<li>Shore, D. I., Klein, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+effects+of+scene+inversion+on+change+blindness%5BTitle%5D)+AND+%22The+Journal+of+General+Psychology%22%5BJournal%5D)">The effects of scene inversion on change blindness.</a> The Journal of General Psychology. 127 (1), 27-43 (2000).</li>
<li>Scharlau, I., Neumann, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Temporal+parameters+and+time+course+of+perceptual+latency+priming%5BTitle%5D)+AND+%22Acta+Psychologica%22%5BJournal%5D)">Temporal parameters and time course of perceptual latency priming.</a> Acta Psychologica. 113 (2), 185-203 (2003).</li>
<li>Schneider, K. A., Bavelier, D. <a target="_blank" href="https://www.ncbi.nlm.nih.gov/pubmed/14642288">Components of visual prior entry.</a> Cognitive Psychology. 47 (4), 333-366 (2003).</li>
<li>Scharlau, I., Neumann, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Perceptual+latency+priming+by+masked+and+unmasked+stimuli%3A+Evidence+for+an+attentional+interpretation%5BTitle%5D)+AND+%22Psychological+Research%22%5BJournal%5D)">Perceptual latency priming by masked and unmasked stimuli: Evidence for an attentional interpretation.</a> Psychological Research. 67 (3), 184-196 (2003).</li>
<li>Shore, D. I., Spence, C., Klein, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Visual+prior+entry%5BTitle%5D)+AND+%22Psychological+Science%22%5BJournal%5D)">Visual prior entry.</a> Psychological Science. 12 (3), 205-212 (2001).</li>
<li>Alcalá-Quintana, R., García-Pérez, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Fitting+model-based+psychometric+functions+to+simultaneity+and+temporal-order+judgment+data%3A+MATLAB+and+R+routines%5BTitle%5D)+AND+%22Behavior+Research+Methods%22%5BJournal%5D)">Fitting model-based psychometric functions to simultaneity and temporal-order judgment data: MATLAB and R routines.</a> Behavior Research Methods. 45 (4), 972-998 (2013).</li>
<li>Hoffman, M. D., Gelman, A. <a target="_blank" href="https://arxiv.org/abs/1111.4246">The No-U-turn sampler: adaptively setting path lengths in Hamiltonian Monte Carlo.</a> Journal of Machine Learning Research. 15 (1), 1593-1623 (2014).</li>
<li>Lee, M. D., Wagenmakers, E. J. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aLee%2C+MD+%22Bayesian+cognitive+modeling%3A+A+practical+course%22">Bayesian cognitive modeling: A practical course</a>. , Cambridge University Press. Cambridge, UK. (2014).</li>
<li>Vangkilde, S., Bundesen, C., Coull, J. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Prompt+but+inefficient%3A+Nicotine+differentially+modulates+discrete+components+of+attention%5BTitle%5D)+AND+%22Psychopharmacology%22%5BJournal%5D)">Prompt but inefficient: Nicotine differentially modulates discrete components of attention.</a> Psychopharmacology. 218 (4), 667-680 (2011).</li>
<li>Tünnermann, J., Scharlau, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Peripheral+Visual+Cues%3A+Their+Fate+in+Processing+and+Effects+on+Attention+and+Temporal-order%5BTitle%5D)+AND+%22Front.+Psychol%22%5BJournal%5D)">Peripheral Visual Cues: Their Fate in Processing and Effects on Attention and Temporal-order.</a> Front. Psychol. 7 (1442), (2016).</li>
</ol>

The authors have nothing to disclose.

The protocol in this article describes how to conduct simple TOJs and fit the data with models based on fundamental stimulus encoding. Three experiments demonstrated how the results can be evaluated in a hierarchical Bayesian estimation framework to assess the influence of attention in highly different stimulus material. Salience in pop-out displays led to increased attentional weights. Also, increased weights were estimated for action space objects in natural images. However, due to the persisting advantage when spatial...

How attention is distributed in space and time is one of the most important factors in human visual perception. Objects that capture attention because of their conspicuity or importance are typically processed faster and with higher accuracy. In behavioral research, such performance benefits have been demonstrated in a variety of experimental paradigms. For instance, allocating attention to the target location speeds up the reaction in probe detection tasks1. Similarly, the accuracy of reporting letters is improved by attention2. Such findings prove that attention enhances processing, but they remain hopelessly mute about how this enhancement is established.
The present paper shows that low-level mechanisms behind attentional advantages can be assessed by measuring the processing speed of individual stimuli in a model-based framework that relates the measurements to fine-grained components of attention. With such a model, the overall processing capacity and its distribution among the stimuli can be inferred from processing speed measurements.
Bundesen's Theory of Visual Attention (TVA)3 provides a suitable model for this endeavor. It is typically applied to data from letter report tasks. In the following, the fundamentals of TVA are explained and it is shown how they can be extended to model temporal-order judgment (TOJ) data obtained with (almost) arbitrary stimuli. This novel method provides estimates of processing speed and resource distribution which can be readily interpreted. The protocol in this article explains how to plan and conduct such experiments and details how the data can be analyzed.
As mentioned above, the usual paradigm in TVA-based modeling and estimation of attention parameters is the letter report task. Participants report the identities of a set of letters which is briefly flashed and typically masked after a varying delay. Among other parameters, the rate at which visual elements are encoded into visual short-term memory can be estimated. The method has been successfully applied to questions in fundamental and clinical research. For instance, Bublak and colleagues4 assessed which attentional parameters are affected in different stages of age-related cognitive deficits. In fundamental attention research, Petersen, Kyllingsbæk, and Bundesen5 used TVA to model the attentional dwell time effect, the observer's difficulty in perceiving the second of two targets at certain time intervals. A major drawback of the letter report paradigm is that it requires sufficiently overlearned and maskable stimuli. This requirement limits the method to letters and digits. Other stimuli would require heavy training of participants.
The TOJ paradigm requires neither specific stimuli nor masking. It can be used with any kind of stimuli for which the order of appearance can be judged. This extends the stimulus range to pretty much everything that could be of interest, including direct cross-modal comparisons6.
Investigating attention with TOJs is based on the phenomenon of attentional prior entry which is a measure of how much earlier an attended stimulus is perceived compared to an unattended one. Unfortunately, the usual method for analyzing TOJ data, fitting observer performance psychometric functions (such as cumulative Gaussian or logistic functions), cannot distinguish whether attention increases the processing rate of the attended stimulus or if it decreases the rate of the unattended stimulus7. This ambiguity is a major problem because the question whether the perception of a stimulus is truly enhanced or if it benefits because of the withdrawal of resources from a competing stimulus is a question of both fundamental and practical relevance. For instance, for the design of human-machine interfaces it is highly relevant to know if increasing the prominence of one element works at the expense of another one.
The TOJ task usually proceeds as follows: A fixation mark is presented for a brief delay, typically a randomly drawn interval shorter than a second. Then, the first target is presented, followed after a variable stimulus onset asynchrony (SOA) by the second target. At negative SOAs, the probe, the attended stimulus, is shown first. At positive SOAs, the reference, the unattended stimulus, leads. At an SOA of zero, both targets are shown simultaneously.
Typically, presenting the target refers to switching the stimulus on. Under certain conditions, however, other temporal events, such as a flicker of an already present target or offsets are used8.
In TOJs, responses are collected in an unspeeded manner, usually by keys mapped to the stimulus identities and presentation orders (e.g., if stimuli are squares and diamonds, one key indicates "square first" and another one "diamond first"). Importantly, for the evaluation, these judgments must be converted to "probe first" (or "reference first") judgments.
In the present work, a combination of the processing model of TVA and the TOJ experimental paradigm is used to eliminate the problems in either individual domain. With this method, readily interpretable speed parameters can be estimated for almost arbitrary visual stimuli, enabling to infer how the observer's attention is allocated to competing visual elements.
The model is based on TVA's equations for the processing of individual stimuli, which will be shortly explained in the following. The probability that one stimulus is encoded into visual short-term memory before the other is interpreted as the probability of judging this stimulus as appearing first. The individual encoding durations are exponentially distributed9:
<img alt="Function F(t) formula, exponential decay, time-dependent, graph analysis, scientific research." src="/files/ftp_upload/54856/54856eq1.jpg" data-altupdatedat="1788235205000" data-alt="Equation 1"> (1)
The maximum ineffective exposure duration t0 is a threshold before which nothing is encoded at all. According to TVA, the rate vx,i at which object x is encoded as member of a perceptual category i (such as color or a shape) is given by the rate equation,
<img alt="Mathematical formula: velocity calculation, symbol equation, research analysis, image processing." src="/files/ftp_upload/54856/54856eq2.jpg" data-altupdatedat="1788235205000" data-alt="Equation 2"> . (2)
The strength of the sensory evidence that x belongs to category i is expressed in ηx,i, and βi is a decision bias for categorizing stimuli as members of category i. This is multiplied by attentional weights. Individual attentional weights wx are divided by the attentional weights of all objects in the visual field. Hence, the relative attentional weight is calculated as
<img alt="Equation: wx = Σ(ηx,i * πj); Symbolic representation in statistical analysis." src="/files/ftp_upload/54856/54856eq3.jpg" data-altupdatedat="1788235205000" data-alt="Equation 3">  (3)
where R represents all categories and ηx,i represents the sensory evidence that object x belongs to category j. The value πj is called pertinence of category j and reflects a bias to make categorizations in j. The overall processing capacity C is the sum of all processing rates for all stimuli and categorizations. For a more detailed description of TVA, refer to Bundesen and Habekost's book9.
In our novel method, Equation 1, which describes the encoding of individual stimuli, is transformed into a model of TOJs. Assuming that selection biases and report categories are constant within an experimental task, the processing rates vp and vr of the two target stimuli probe (p) and reference (r) depend on C and the attentional weights in the form vp= C · wp and vr = C · wr, respectively. The new TOJ model expresses the success probability Pp1st that a participant judges the probe stimulus to be first as a function of the SOA and the processing rates. It can be formalized as follows:
<img alt="Static equilibrium formula; P_gst(ν_p,ν_r,SOA); mathematical equation." src="/files/ftp_upload/54856/54856eq4.jpg" data-altupdatedat="1788235205000" data-alt="Equation 4"> (4)
A more detailed description of how this equation is derived from the basic TVA equations is described by Tünnermann, Petersen, and Scharlau7.
For the sake of simplicity, the parameter t0 is omitted in the model in Equation 1. According to the original TVA, t0 should be identical for both targets in the TOJ task, and, therefore, it cancels out. However, this assumption may sometimes be violated (see section Discussion).
For fitting this equation to TOJ data, a hierarchical Bayesian estimation scheme11 is suggested. This approach allows to estimate the attentional weights wp and wr of the probe and reference stimuli and the overall processing rate C. These parameters, the resulting uptake rates vp and vr, and attention-induced differences between them, can be assessed on the subject and group levels along with estimated uncertainties. The hierarchical model is illustrated in Figure 1. During the planning stage for an experiment, convenient Bayesian power analysis can be conducted.
The following protocol describes how to plan, execute and analyze TOJ experiments from which processing speed parameters and attentional weights for visual stimuli can be obtained. The protocol assumes that the researcher is interested in how an attentional manipulation influences the processing speeds of some targets of interest.
<img alt="Bayesian network diagram with equations for cognitive model analysis of subjects and SOAs." src="/files/ftp_upload/54856/54856fig1.jpg" data-altupdatedat="1788235205000" data-alt="Figure 1">
Figure 1: Graphical model used in the Bayesian estimation procedure. Circles indicate estimated distributions; double circles indicate deterministic nodes. Squares indicate data. The relations are given on the right side of the figure. The nodes outside the rounded frames (“plates”) represent mean and dispersion estimates of TVA parameters (see Introduction) on the group level. In the “j Subjects” plate, it can be seen how attentional weights (w) are combined with the overall processing rates (C) to from stimulus processing rates (v) on the subject level. Plate “i SOAs” shows how these TVA parameters are then transformed (via the function Pp1st described in the Introduction) into the success probability (θ) for the binomially distributed responses at each SOA. Therefore, the θ together with the repetitions of the SOA (n) describe the data points (y). For more details on notation and interpretation of graphical models, refer to Lee and Wagenmakers23. Note that for the sake of clarity, the nodes that represent differences of parameters have been omitted. These deterministic parameters are indicated in the figures of the experimental results instead. <a href="http://cloudflare.jove.com/files/ftp_upload/54856/54856fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

<table><tbody><tr><td>Personal Computer</td><td></td><td></td><td></td></tr><tr><td>(Open Source) Experimentation and evaluation software</td><td></td><td></td><td></td></tr></tbody></table>

measuring attention and visual processing speed by model-based analysis of temporal-order judgments

Measuring Attention and Visual Processing Speed by Model-based Analysis of Temporal-order Judgments

This protocol describes how to conduct temporal-order experiments to measure visual processing speed and the attentional resource distribution. The proposed method is based on a new and synergistic combination of three components: the temporal-order judgments (TOJ) paradigm, Bundesen&#39;s Theory of Visual Attention (TVA), and a hierarchical Bayesian estimation framework. The method provides readily interpretable parameters, which are supported by the theoretical and neurophysiological underpinnings of TVA. Using TOJs, TVA-based estimates can be obtained for a broad range of stimuli, whereas traditional paradigms used with TVA are mainly limited to letters and digits. Finally, the meaningful parameters of the proposed model allow for the establishment of a hierarchical Bayesian model. Such a statistical model allows assessing results in one coherent analysis both on the subject and the group level.
To demonstrate the feasibility and versatility of this new approach, three experiments are reported with attention manipulations in synthetic pop-out displays, natural images, and a cued letter-report paradigm.

In the following, results obtained with the proposed method are reported. Three experiments measured the influence of different attentional manipulations with three highly different types of stimulus material. The stimuli are simple line segments in pop-out patterns, action space objects in natural images, and cued letter targets.
Experiment 1: Salience in pop-out displays 
Experiment 1 aimed at measuring the influence of vis...

Temporal-order judgments can be used to estimate processing speed parameters and attentional weights and thereby to infer the mechanisms of attentional processing. This methodology can be applied to a wide range of visual stimuli and works with many attention manipulations.

This protocol describes how to conduct temporal-order experiments to measure visual processing speed and the attentional resource distribution. The ...

The overall goal of this protocol is measure parameters of attention and visual processing for almost arbitrary stimuli. This is accomplished by modelling data from temporal order judgements, TOJs. In these, participants judge the presentation order of two targets, the resulting data is analyzed with a novel model that allows to measure how attention affects stimulus encoding rates.Bundesen's theory of visual attention provides various use for parameters, such as attentional weight, and processing rates. Typically these are estimated in item report tasks where letters or digits are used, using anything other than letters or digits is difficult and requires intensive training and therefore is rarely done. For example, it's difficult to imagine how one would measure visuals salience and pop-out displays with this method.Therefore we propose a novel TVA-based method, which uses temporal order judgment that can be conducted with almost arbitrary stimuli. Temporal order judgments have been used to assess attention for a long time, but combined with TVA, they become more powerful, providing readily interpretable parameters. In the temporal order judgment task, two stimuli, here identifie

measuring-attention-visual-processing-speed-model-based-analysis

Research

JoVE Journal

Behavior

Eye tracking has long been used to study gaze patterns in typically-developing individuals, but recent technological advancements have made its use with clinical populations, including autism, more feasible. While eye-tracking young children with autism can offer insight into early symptom manifestations, it involves methodological challenges. Suggestions for best practices are provided.

Eye Tracking Young Children with Autism

This paper describes a novel dual task procedure combined with Rapid Serial Visual Presentation to look at attentional blink at varied stimulus onset asynchronies. This experimental procedure differed from others in that it tested attentional blink for nontargets.

A Dual Task Procedure Combined with Rapid Serial Visual Presentation to Test Attentional Blink for Nontargets

To replicate laboratory settings, online data collection methods for visual tasks require tight control over stimulus presentation. We outline methods for the use of a web application to collect performance data on two tests of visual attention.

Methods to Test Visual Attention Online

We describe how to implement a battery of behavioral tasks to examine the processing and integration of sensory stimuli in children with ASD. The goal is to characterize individual differences in temporal processing of simple auditory and visual stimuli and relate these to higher order perceptual skills like speech perception.

Testing Sensory and Multisensory Function in Children with Autism Spectrum Disorder

Attention control comprises enhancement of target signals and attenuation of distractor signals. We describe an approach to measure separately but concurrently, the neurophysiology of attending and ignoring in sustained intermodal attention, utilizing a passive control condition during which neither process is continuously engaged.

Measurement of Neurophysiological Signals of Ignoring and Attending Processes in Attention Control

A method is described to quantify the quality of visual information processing based on reflexive eye movements in response to specific visual modalities. Reaction times and fixation output parameters are used to characterize visual performance in children with and without visual impairments from 6 months of age.

A Method to Quantify Visual Information Processing in Children Using Eye Tracking

This is a qualitative comparative case study analysis of eye-tracking data on the first moments of social video scenes as viewed by three participants: one with autism spectrum disorder, one with comorbid attention deficit-hyperactive disorder, and one neurotypical control.

Comparing Eye-tracking Data of Children with High-functioning ASD, Comorbid ADHD, and of a Control Watching Social Videos

This experimental protocol combined eye tracking and the assessment of presaccadic visual sensitivity in a dual task paradigm, consisting of a free choice saccade task and a visual discrimination task, to investigate the deployment of visual spatial attention before both, accurate and averaging saccades.

Investigating the Deployment of Visual Attention Before Accurate and Averaging Saccades via Eye Tracking and Assessment of Visual Sensitivity

We present a protocol that employs eye tracking to monitor eye movements during an interval comparison (duration perception) task based on visual events. The aim is to provide a preliminary guide to separate oculomotor responses to duration perception tasks (comparison or discrimination of time intervals) from responses to the stimulus itself.

Eye Movements in Visual Duration Perception: Disentangling Stimulus from Time in Predecisional Processes

It is important to obtain unbiased estimates of visual population receptive fields (pRFs) by functional magnetic resonance imaging. We use mild regularization constraints to estimate pRF topography without a-priori assumptions about pRF shape, allowing us to choose specific pRF models post-hoc. This is particularly advantageous in subjects with visual-pathway lesions.

Topographical Estimation of Visual Population Receptive Fields by fMRI

배우세요 시간적 순서 심판(TOJ)을 사용하여 주의 및 시각 처리 속도를 측정하는 방법을. Bundesen의 시각 주의 이론 기반 모델을 활용해 거의 모든 자극에 적용 가능하며, 베이지안 계층적 분석으로 주의 가중치와 인코딩 속도를 정량화합니다.

Measuring Attention and Visual Processing Speed by Model-based Analysis of Temporal-order Judgments

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