There is a moment in certain police encounters when everything seems to happen at once. The officer is confronting an agitated individual who has repeatedly ignored verbal commands. The subject's right hand moves toward his waistband. Almost simultaneously, the officer's radio broadcasts a fresh update from dispatch. A second officer moves into the peripheral field of view, partially obscuring the subject. Someone nearby begins shouting. The subject's hand disappears beneath his clothing, and the officer must determine whether the movement represents an imminent threat, an innocent adjustment or something else entirely. Meanwhile, the officer is attempting to maintain distance, communicate effectively, account for the partner's position and prepare an appropriate response. 

From the perspective of someone watching the encounter afterward, these may appear to be separate, relatively simple tasks. Listen to the radio. Watch the hands. Maintain awareness of the partner. Issue commands. Recognize a threat. Respond appropriately. Each seems straightforward enough when considered individually. The problem is that the human brain does not necessarily process multiple competing decisions as efficiently as it processes them in isolation. When those decisions arrive in rapid succession, something rather interesting happens. The second decision may be delayed, not because the individual failed to perceive the relevant information, but because critical processing resources are already occupied by the first. 

The Hidden Delay in Split-Second Decisions

Cognitive psychologists have studied this phenomenon for decades. It is known as the psychological refractory period, or PRP, and I believe its implications for law enforcement training deserve considerably more attention than they have received. For those unfamiliar with the term, the psychological refractory period describes a predictable delay in responding to a second stimulus when two tasks requiring responses are presented close together in time. In conventional laboratory experiments, a participant might hear a tone requiring one response, followed almost immediately by a visual signal requiring another. When the interval between the two stimuli is sufficiently short, the response to the second stimulus becomes disproportionately slower, even when the participant can perform each task quickly and accurately on its own (Pashler, 1994). 

It would be inaccurate, however, to take this research to mean that the human brain simply cannot process two things at once. It can. Multiple streams of sensory information can be processed concurrently, and some perceptual and motor operations can overlap. An officer, for example, may visually register a suspect's hand movement while simultaneously hearing a partner speak or receiving radio traffic. The limitation becomes more pronounced when two or more demands require central cognitive operations such as interpretation, prioritization, response selection or the initiation of separate actions. Research on the psychological refractory period demonstrates that when two response-demanding tasks occur in rapid succession, processing associated with the second task can be delayed even though some perceptual processing has already begun (Pashler, 1994; Zylberberg et al., 2012; Klapp et al., 2019). The problem, then, is not that the brain suddenly becomes incapable of receiving more than one source of information. The problem is that some stages of deciding what that information means and what to do about it encounter a processing bottleneck. 

It is equally important not to describe the PRP as though it represents a fixed period of time. There is no universal 200-millisecond (.200-second) or 300-millisecond (.300-second) PRP that can simply be added to every human reaction. The size of the delay depends on the tasks being performed, their relative complexity and, critically, how closely together the two stimuli occur. Reviews of the dual-task literature have found that interference in the second task is especially evident when two response-demanding tasks overlap or when the second stimulus appears within approximately 500 milliseconds (.500 seconds) of the first. As the interval between the two stimuli increases and the amount of processing overlap decreases, reaction time to the second task generally improves (Pashler, 1994; Hirsch & Koch, 2026). 

What the Research Reveals About Competing Tasks

One particularly useful illustration comes from work by Jentzsch, Leuthold and Ulrich (2007). In their experiment, participants first categorized a tone and then categorized a visually presented letter. The interval between the onset of the first and second stimulus, known as the stimulus-onset asynchrony or SOA, was varied. When the second stimulus appeared only 100 milliseconds (.100 seconds) after the first, mean reaction time to Task 2 was 737 milliseconds (.737 seconds). When the interval increased to 400 milliseconds (.400 seconds), Task 2 reaction time fell to 525 milliseconds (.525 seconds). At an 800-millisecond (.800-second) interval, mean Task 2 reaction time fell further to 444 milliseconds (.444 seconds) (Jentzsch et al., 2007; Hirsch & Koch, 2026). The difference between the shortest- and longest-overlap conditions was therefore approximately 293 milliseconds (.293 seconds). That is not evidence that the PRP itself “lasts” 293 milliseconds (.293 seconds). It demonstrates something more useful: Increasing the temporal overlap between two relatively simple response-demanding tasks was associated with almost three-tenths of a second of additional delay in responding to the second task. 

To appreciate what 293 milliseconds (.293 seconds) can represent in a firearms context, consider Force Science research on trigger response. In the Tempe study involving 102 police officers, Lewinski and Hudson found that officers responding to a simple visual stimulus required approximately 310 milliseconds (.310 seconds) from stimulus presentation to completion of the trigger response. Subsequent summaries of the study report that approximately 230 to 250 milliseconds (.230 to .250 seconds) of that interval involved perceiving and processing the stimulus, while only about 60 to 80 milliseconds (.060 to .080 seconds) represented the physical movement required to complete the trigger press (Lewinski & Hudson, 2003). 

The comparison is striking. The approximately 293-millisecond (.293-second) increase associated with heavy dual-task overlap in the Jentzsch experiment is almost as long as the entire 310-millisecond (.310-second) visual-cue-to-trigger response measured in the Tempe study. It is also several times longer than the mechanical trigger movement itself. Other Force Science-associated instructional discussions have reported rapid firing cadences in the neighborhood of 250 milliseconds (.250 seconds) per shot, or faster, which further illustrates how much activity can occur inside a quarter of a second. Put another way, an experimentally demonstrated cognitive delay approaching 300 milliseconds (.300 seconds) occupies roughly the same amount of time in which a trained shooter may be capable of completing another trigger cycle. 

That comparison should not be interpreted as evidence that PRP interference causes an officer to fire an additional round. It simply illustrates how operationally consequential a few hundred milliseconds can become when events are unfolding at firearm speeds. That distinction is important. A laboratory result cannot simply be converted into a prediction that an officer will be delayed by 293 milliseconds (.293 seconds) during a particular confrontation. Police encounters involve variables that do not exist in controlled PRP experiments, including uncertainty, movement, emotional arousal, environmental complexity, threat appraisal, communication and potentially severe consequences for error. What the laboratory literature establishes is the underlying human-performance limitation. When response-demanding tasks occur close together in time, the second response can be substantially delayed because portions of the cognitive system are still occupied with the first. The operational significance is not found in assigning officers a universal PRP number. It is found in recognizing that fractions of a second can be consumed by cognitive competition before the officer ever begins executing the response we later observe. 

Why This Matters on the Street

I make essentially this same distinction in Unlocking the Brain Code. In discussing the cognitive demands of real-world performance, I wrote that “working memory limitations and attentional constraints mean that not all information can be processed simultaneously,” adding that “training that isolates technique from competing cognitive demands does not prepare learners for this bottleneck effect” (Hanson, 2026, p. 176). That distinction becomes especially important in policing. An officer may see the hands, hear the radio, recognize a bystander and perceive a partner's movement within roughly the same window of time. What cannot safely be assumed is that each piece of information can be consciously interpreted, prioritized and converted into an independent response with equal efficiency at precisely the same instant. The distinction between concurrent perception and constrained response processing is where the psychological refractory period becomes operationally significant. 

What makes this particularly fascinating is that the delay is not necessarily attributable to poor attention, inadequate motivation or an inability to recognize the second stimulus. In many experimental conditions, sensory information associated with the second task can begin processing while the first task is underway. The difficulty emerges at a later stage, when the brain must select, organize or initiate the appropriate response. Depending on the task and the theoretical model, some of these operations cannot proceed independently without interference. In practical terms, the brain encounters something resembling a traffic jam. 

The first vehicle has entered a narrow section of roadway. The second vehicle can approach, and its driver may clearly see the road ahead, but passage through the restricted section is temporarily unavailable. Adding another vehicle does not increase the roadway's capacity. It simply creates another demand on a system that is already occupied. That analogy is useful, although it is not a literal description of brain anatomy. There is no single neurological tollbooth through which every decision must pass. Contemporary research identifies several interacting limitations involving response selection, task coordination, working memory and the initiation of action. 

Indeed, Klapp, Maslovat and Jagacinski (2019) challenged the traditional assumption that the PRP bottleneck resides exclusively in response selection, arguing that response initiation and its timing are important components of the effect. Their work reinforces an important point: The observed delay is well established, but the precise mechanisms responsible for it remain subjects of scientific investigation. For police trainers, the distinction between competing explanations is interesting. The operational consequence is considerably more significant. Under certain conditions, two individually manageable demands can produce a combined performance burden that is far greater than either demand would suggest. 

The Limits of Traditional Performance Metrics

Consider what this means for the way we evaluate officer performance. We routinely measure how quickly an officer can draw a pistol, acquire an acceptable sight picture, fire an accurate shot, conduct a reload or deliver a verbal command. We often measure these activities separately, under predictable conditions, and then assume the resulting performance represents a reliable indication of how efficiently the officer can perform during a rapidly evolving confrontation. That assumption deserves serious scrutiny because a police officer does not ordinarily encounter a deadly threat as an isolated visual stimulus, conveniently separated from every other operational responsibility. 

Threat recognition may occur while the officer is communicating, moving, interpreting ambiguous behavior, coordinating with another officer or attempting to resolve an equipment problem. The mechanical act of drawing and firing may be well rehearsed, but the decision to initiate that act must compete with other demands that do not conveniently disappear simply because the situation has become dangerous. The psychological refractory period offers a scientific explanation for why that distinction is so consequential. 

One of the more important contributions to this discussion comes from research by Zylberberg, Ouellette, Sigman and Roelfsema (2012), who examined decision-making during the psychological refractory period. Their findings demonstrated that decision processes can interact in ways that produce delays when tasks compete for limited processing resources. The research also suggests that the brain's handling of competing decisions is more nuanced than simply processing one complete task before beginning another. Some operations can overlap, while others remain constrained by the demands of the competing task. 

This distinction becomes especially relevant when examining police encounters because perception, interpretation and action are not interchangeable processes. An officer may visually register a suspect's hand movement without immediately determining its significance. The officer may recognize an emerging threat but experience interference while organizing an appropriate response. Alternatively, the officer may initiate an action before adequately resolving competing information, producing a response that is fast but inappropriate. These are different performance failures, and they should not automatically receive the same instructional diagnosis. 

This also helps explain why the psychological refractory period should not be confused with Hick's Law, although the two concepts are related. Hick's Law concerns the relationship between the number of response alternatives and the time required to select among them under certain experimental conditions (Hick, 1952). The psychological refractory period addresses interference that emerges when multiple tasks or decisions arrive close together in time. One concerns the complexity of choosing among alternatives. The other concerns what happens when the brain must contend with competing response demands before earlier processing has sufficiently progressed. 

An officer can therefore experience a substantial delay even when neither individual decision is especially complicated. The critical variable may not be the number of available choices, but the temporal relationship between competing demands. That is a fundamentally different problem from simply asking officers to make faster decisions. Consider a relatively ordinary firearms training exercise. An officer stands on a firing line and responds to an instructor's command to draw and fire two rounds into a designated target. The officer knows the target, understands the required response and anticipates the command. With sufficient repetition, the motor sequence becomes increasingly efficient. The draw is smooth, the sights arrive consistently, and the shots are delivered within an impressive interval. The instructor records the performance and concludes that the officer has demonstrated a high level of proficiency. 

Now introduce a second task that requires an independent decision. The officer must identify whether a rapidly presented object represents a weapon while simultaneously responding to a separate communication requiring acknowledgment. The two demands are presented at varying intervals, sometimes almost simultaneously and sometimes separated by enough time to permit the first response to progress substantially. Under those conditions, the officer's response to the second task may become slower even though neither the firearm manipulation nor the communication task has become mechanically more difficult. The critical change is the temporal overlap between the decisions. 

Importantly, that result should not automatically be interpreted as evidence of a PRP effect. Realistic exercises introduce numerous additional variables, including divided attention, task switching, uncertainty and response conflict. Demonstrating a PRP effect experimentally requires carefully controlled stimulus timing and task conditions. Nevertheless, the exercise illustrates why instructors should become interested in the timing and interaction of cognitive demands rather than concentrating exclusively on the speed of isolated motor performance. 

The distinction becomes even more significant when the second task requires the officer to inhibit an otherwise well-practiced response. For example, a shooter who has repeatedly practiced firing immediately upon target presentation may develop a strong association between target appearance and trigger activation. When a later exercise introduces targets that require discrimination, the shooter must determine whether firing is appropriate rather than simply executing a familiar motor sequence. If an unrelated decision competes for processing resources at nearly the same instant, the officer may experience delayed recognition, delayed action or difficulty suppressing the previously reinforced response. 

Research by Smith and Boolani (2024) examined a nonanticipatory, random-action target system intended to challenge shooting performance under unpredictable target presentations. Their small feasibility study, involving six experienced shooters, suggested potential benefits from training that varies target exposure and reduces predictability. The study did not establish that the system reduces PRP interference, and its sample was far too small to support broad claims about operational performance. It did, however, reinforce the importance of examining shooting accuracy alongside omission and commission errors when the environment becomes less predictable. 

When Speed Creates New Risks

This brings us to a distinction which I believe deserves greater emphasis in police firearms training. An omission error occurs when an appropriate response is not executed. A commission error occurs when an inappropriate response is executed. In defensive firearms applications, either can carry catastrophic consequences. An officer who fails to respond to a genuine deadly threat may be seriously injured or killed. An officer who fires at a person who does not present a legally sufficient threat may inflict an irreversible injury on someone who should never have been shot. 

A training program that rewards speed without adequately examining response inhibition can inadvertently encourage the very behavior it should be attempting to prevent. Conversely, a program that emphasizes deliberate discrimination without developing efficient recognition and action may produce unnecessary delays when immediate intervention is justified. The objective is not simply faster performance or more cautious performance. It is an appropriately calibrated response to the actual circumstances, and that calibration becomes increasingly difficult when competing demands arrive almost simultaneously. 

There is another complication that deserves attention. The psychological refractory period is not synonymous with the effects of acute physiological stress. The two can interact in operational environments, but they represent distinguishable mechanisms. PRP effects have been demonstrated in controlled laboratory conditions without requiring participants to experience fear, perceived mortal danger or substantial sympathetic nervous system activation. The bottleneck can emerge because of the structure and timing of the tasks themselves. 

Acute stress introduces additional complications involving attention, perception, motor control and physiological regulation. Anderson, Di Nota, Metz and Andersen (2019) reviewed evidence demonstrating how stress physiology can degrade skilled motor performance relevant to policing. Their analysis emphasized that police performance cannot be understood solely through higher-order cognitive processes because the physiological response to stress also influences the physical execution of learned skills. Similarly, Baldwin and colleagues (2019) examined physiological responses among 64 police officers during actual calls for service. Their findings demonstrated that operational circumstances, including encountering subjects and responding to higher-risk incidents, influence physiological arousal. 

These findings do not establish that acute stress increases PRP delays by a particular amount. They do, however, establish that officers operate within a physiological environment considerably more complicated than the conditions used to measure most isolated reaction-time tasks. When cognitive competition and acute stress occur together, it is reasonable to anticipate additional challenges to performance. The exact relationship will depend on the demands involved, the officer's experience, the characteristics of the threat and the specific cognitive operations required. We should resist the temptation to reduce these interactions to a simplistic formula suggesting that a certain heart rate produces a predictable decision-making delay because the human nervous system is not that accommodating. 

I also believe this research should influence how we interpret the familiar concept of tunnel vision. Within police training, tunnel vision is frequently invoked to explain failures to recognize information outside an officer's immediate focus. Sometimes that description is appropriate. Attentional narrowing under stress is a documented phenomenon, and officers can become excessively focused on particular threat-related information. However, not every failure to respond to available information represents tunnel vision. 

An officer may perceive a stimulus but fail to process its significance promptly. Another may recognize the information but experience interference while selecting a response. A third may successfully interpret the information yet fail to initiate the intended action quickly enough. These mechanisms can produce superficially similar outcomes while requiring different explanations. That is why I become concerned when instructors diagnose every observable hesitation as indecision, every missed cue as tunnel vision and every delayed response as inadequate training. Those explanations may occasionally be correct, but they are not sufficiently precise to guide meaningful corrective instruction. 

In Unlocking the Brain Code, I wrote: “Students trained exclusively in stable, predictable environments often exhibit performance decay when conditions change” (Hanson, 2026, p. 170). The broader discussion in that section addresses the consequences of instructional environments that prioritize mechanical repetition while neglecting contextual adaptability. The psychological refractory period adds another dimension to that argument because it suggests that the timing of competing demands may expose performance limitations that remain completely invisible when skills are practiced individually. 

Building Training Around Cognitive Reality

This is where the NeuralTac framework becomes particularly useful. NeuralTac approaches high-liability instruction from the premise that effective training must develop durable, transferable capabilities rather than merely produce impressive performance under familiar conditions. The framework integrates motor learning, cognitive psychology, perceptual decision-making, ecological dynamics and appropriately designed stress exposure to help instructors understand how training conditions influence subsequent performance. 

Applied to the psychological refractory period, this means examining not simply whether an officer can perform multiple tasks, but how those tasks interact, how their timing affects performance and whether the officer can recognize and prioritize relevant information without becoming dependent on a predetermined sequence. That does not mean we should immediately begin overwhelming students with simultaneous demands. In fact, indiscriminately increasing cognitive complexity may accomplish very little beyond producing confusion, frustration and a collection of entertaining training failures. There is an important difference between designing productive cognitive interference and simply creating chaos. 

Consider a relatively inexperienced officer who is still developing reliable firearm manipulation skills. If that officer must consciously attend to every component of the draw, grip establishment, sight acquisition and trigger manipulation, those operations may consume considerable attentional resources. Introducing several unrelated decision-making tasks before the foundational movements have become sufficiently stable may create excessive interference without producing meaningful learning. The appropriate instructional response is not to eliminate complexity indefinitely. It is to introduce complexity progressively, allowing the learner to develop reliable motor capabilities while gradually increasing the perceptual and decision-making demands associated with their application. 

This is consistent with the broader motor learning literature. Fitts and Posner (1967) described the progression from cognitively demanding early performance toward more efficient and increasingly automatic execution. Although the boundaries between learning stages are not always discrete, the underlying principle remains useful. As motor skills become more proficient, they may require less conscious attention, potentially allowing more resources to be directed toward environmental interpretation and decision-making. 

However, automaticity is not a magical exemption from cognitive limitations. An officer who can execute a reload with minimal conscious attention may still experience interference when the situation requires competing decisions, unexpected changes or deliberate inhibition of a familiar response. Moreover, automatic responses can become liabilities when they are strongly associated with training conditions that do not accurately represent operational requirements. 

This is precisely why the NeuralTac emphasis on contextual variability and adaptable performance is so important. The goal is not to eliminate every processing limitation, which is neither realistic nor supported by the research. It is to develop performers who can recognize meaningful information efficiently, execute well-learned movements without unnecessary cognitive expenditure and adapt when competing demands disrupt an anticipated sequence. 

There is also a compelling connection to recognition-primed decision-making. Gary Klein's research demonstrated that experienced decision-makers often rely on recognizable patterns and familiar situational relationships rather than consciously comparing numerous alternatives (Klein, 1993). This can substantially improve decision efficiency when the environment contains meaningful cues that the performer has learned to interpret. 

For law enforcement, that suggests a valuable instructional opportunity. Officers who have developed rich, accurate mental representations of common operational problems may be better positioned to recognize relevant patterns without requiring prolonged deliberation. An officer who understands how weapon-access movements differ across contexts, for example, may interpret an unfolding situation more efficiently than someone whose experience consists primarily of responding to standardized target presentations. But there is a critical qualification: Recognition is only as reliable as the experiences upon which it is built. If training repeatedly reinforces narrow associations, such as treating every rapid hand movement as an imminent weapon presentation, faster recognition may simply produce faster errors. The objective must therefore be accurate recognition, not merely rapid recognition. 

That principle has direct implications for scenario-based training. Rather than designing every exercise around a single obvious threat and an expected response, instructors should expose officers to situations in which the relevant cues vary, competing demands emerge unpredictably and the appropriate outcome cannot be determined simply by remembering the choreography of a previous drill. 

A properly designed scenario might require an officer to communicate with a noncompliant subject while monitoring a second individual, maintaining awareness of a partner and responding to a developing environmental hazard. The instructor could manipulate the timing of selected events to determine whether performance deteriorates when demands overlap. Importantly, the exercise should include opportunities in which restraint, repositioning, communication or disengagement are more appropriate than the application of force. The instructional value would not come from how much confusion the instructor could generate. It would come from identifying the circumstances under which the officer's performance begins to deteriorate, determining the probable causes and developing corrective experiences that improve subsequent performance. 

This requires more sophisticated evaluation than simply recording whether the officer completed the scenario successfully. Instructors should examine when relevant information became available, when the officer appeared to recognize it, how the response unfolded and whether competing demands influenced the outcome. Video review, synchronized scenario events and carefully structured debriefings can help reconstruct these relationships, although observable behavior alone cannot definitively identify a particular cognitive mechanism. 

We should also be cautious about assuming that faster responses always represent better cognitive processing. An officer may respond quickly because the situation was accurately recognized. Another may respond quickly because the training environment encouraged premature action before sufficient information was available. The resulting reaction times may look similar, while the underlying decision quality is profoundly different. 

This is one reason I have long argued that firearms training should distinguish between mechanical proficiency and operational capability. Mechanical proficiency is indispensable, but it is only one component of the larger performance problem. An officer must also recognize when a skill is appropriate, determine whether its application is justified and adapt its execution to circumstances that may be changing faster than the officer can consciously evaluate them. The psychological refractory period exposes the danger of assuming that excellence in isolated tasks necessarily translates into excellence when those tasks compete. 

Lessons for Team Operations and Use-of-Force Reviews

There are implications beyond the individual officer as well. Police operations frequently involve teams, and poorly coordinated communication can introduce additional cognitive demands at precisely the wrong moment. A partner who issues an unnecessary instruction during a rapidly developing threat encounter may inadvertently compete for the receiving officer's processing resources. Similarly, poorly timed radio transmissions may create competing demands when an officer is already attempting to interpret ambiguous behavior and select an appropriate response. 

That does not mean communication should cease during critical incidents. It means communication should be designed and practiced with an appreciation for cognitive workload, timing and operational priority. Clear, concise and relevant communication can support performance. Excessive, ambiguous or poorly timed communication can interfere with it. The distinction is especially important because the cognitive demands imposed by a message are not determined solely by its length. A brief instruction that requires the recipient to reinterpret the situation or change an intended action may create greater interference than a longer communication that is familiar, predictable and immediately relevant. This should encourage agencies to examine their communication practices as components of human performance rather than treating them exclusively as procedural requirements. 

Finally, the psychological refractory period has implications for how we evaluate officer conduct after critical incidents. Video recordings often allow investigators, supervisors and outside observers to examine events repeatedly, isolate individual movements and reconstruct information that was distributed across fractions of a second. That analytical capability is valuable, but it can also create a misleading impression of what was cognitively available to the officer at the time. 

A reviewer may identify a hand movement, a radio transmission, a partner's change in position and an environmental hazard as four distinct pieces of information. The reviewer can pause the recording, examine each independently and then assume that the officer should have processed all four with comparable clarity. The officer did not have that luxury, and the relevant question is not simply whether information was present somewhere in the environment. It is whether that information was perceptually available, sufficiently interpretable and actionable under the actual temporal and cognitive demands of the encounter. The PRP literature provides one scientifically grounded reason why the distinction deserves careful consideration. 

Slightly beyond the immediate PRP discussion, but important enough to mention, I would be remiss if I didn’t bring up a related danger in constructing counterfactuals during use-of-force reviews, particularly when examining what an officer could reasonably perceive, process and act upon within extremely compressed periods of time. Counterfactual analysis can be useful when the purpose is organizational learning. Investigators and trainers should be able to ask whether a different tactic, position, communication strategy or earlier decision might have produced a better outcome. The problem begins when that hypothetical alternative is treated as evidence that the officer reasonably could or should have selected it in the actual moment. Once reviewers know how an encounter ended, they can reconstruct a cleaner sequence of events, isolate individual cues and imagine alternatives with information, time and cognitive capacity the officer did not possess. Research on hindsight bias demonstrates that outcome knowledge can alter subsequent judgments about perceived threat and the quality of lethal-force decisions, reinforcing the need to separate retrospective learning from real-time reasonableness analysis (Goodwill et al., 2010). 

That distinction is especially important in use-of-force review. Asking what might have produced a better outcome can improve training, tactics and policy. Asking whether the officer's actual conduct was reasonable requires a different inquiry grounded in what the officer could perceive, interpret and act upon at the time, not what becomes apparent after repeated video review and knowledge of the outcome. A counterfactual can therefore be useful as a learning tool without becoming proof that the officer should have selected that alternative in real time. 

This does not establish that a particular officer's delay was caused by a psychological refractory period, nor does it excuse unreasonable conduct. It does, however, caution against evaluating human performance as though competing decisions can always be processed independently and without cost. Ultimately, the psychological refractory period challenges a deeply embedded assumption in conventional firearms training: that making individual skills faster will necessarily make the overall performer faster. 

Sometimes it will. Efficient motor execution can reduce unnecessary demands and improve performance. But an officer who can draw a pistol in an exceptionally short interval may still experience substantial delays when the decision to draw competes with other cognitive operations. Conversely, an officer whose mechanical performance is less impressive may demonstrate superior operational judgment because the relevant cues are recognized earlier and the appropriate response is selected more efficiently. The distinction should fundamentally influence what we choose to measure, what we reward and how we structure training. 

For decades, law enforcement instructors have invested enormous effort in improving the speed and precision of individual motor skills. That work has value and should continue. But if we genuinely intend to prepare officers for environments characterized by uncertainty, competing demands and rapidly changing circumstances, we must devote comparable attention to the cognitive architecture within which those skills are selected and executed. 

The psychological refractory period reminds us that the brain is not an unlimited parallel-processing machine. Some operations can proceed simultaneously, others interfere with one another, and the timing of competing demands can influence performance in ways that are neither obvious nor intuitive. We cannot train officers to repeal those limitations, but we can design instruction that acknowledges them, develops more efficient recognition and action, and reduces unnecessary competition for limited cognitive resources. 

I have often argued that the objective of professional firearms training should not be to manufacture a perfect response to a predetermined problem. It should be to develop adaptable capability that remains functional when the problem changes. Understanding the psychological refractory period strengthens that argument because it reveals how quickly apparently manageable tasks can become difficult when the timing of their demands changes. 

The next time an officer hesitates during a scenario, overlooks an apparently obvious cue or struggles to execute a familiar skill while several events unfold simultaneously, I would encourage the instructor to resist the temptation to immediately prescribe more repetitions, faster movement or greater intensity. Instead, ask a more useful question: Was the officer unable to perform the skill, or did the training expose a limitation in the way competing information was being processed? Those are not the same problem, and treating them as though they are can produce precisely the kind of instructional failure we should be working to eliminate. 

The traffic jam may not be in the officer's hands. It may be occurring somewhere between perception, decision and action. Until we learn to recognize that distinction, we will continue trying to solve cognitive problems with mechanical solutions and wondering why the improvements we observe on the firing line do not always survive contact with the real world. 

References 

Anderson, G. S., Di Nota, P. M., Metz, G. A. S., & Andersen, J. P. (2019). The impact of acute stress physiology on skilled motor performance: Implications for policing. Frontiers in Psychology, 10, Article 2501. https://doi.org/10.3389/fpsyg.2019.02501 

Baldwin, S., Bennell, C., Andersen, J. P., Semple, T., & Jenkins, B. (2019). Stress-activity mapping: Physiological responses during general duty police encounters. Frontiers in Psychology, 10, Article 2216. https://doi.org/10.3389/fpsyg.2019.02216 

Fitts, P. M., & Posner, M. I. (1967). Human performance. Brooks/Cole. 

Goodwill, A. M., Alison, L., Lehmann, R., Francis, A. W., & Eyre, M. (2010). The impact of outcome knowledge, role, and quality of information on the perceived legitimacy of lethal force decisions in counter-terrorism operations. Behavioral Sciences & the Law, 28(3), 337–350. https://doi.org/10.1002/bsl.897 

Hanson, K. A. (2026). Unlocking the brain code: Exposing the limits of traditional firearms instruction and high-liability training through neuroscience, psychology, and human performance research. Applied Threat Science Publications. 

Hick, W. E. (1952). On the rate of gain of information. Quarterly Journal of Experimental Psychology, 4(1), 11–26. https://doi.org/10.1080/17470215208416600 

Hirsch, P., & Koch, I. (2026). Advancing an account of hierarchical dual-task control: A focused review on abstract higher-level task representations in dual-task situations. Quarterly Journal of Experimental Psychology, 79(6), 1367–1384. https://doi.org/10.1177/17470218241295524

Jentzsch, I., Leuthold, H., & Ulrich, R. (2007). Decomposing sources of response slowing in the PRP paradigm. Journal of Experimental Psychology: Human Perception and Performance, 33(3), 610–626. https://doi.org/10.1037/0096-1523.33.3.610 

Klapp, S. T., Maslovat, D., & Jagacinski, R. J. (2019). The bottleneck of the psychological refractory period effect involves timing of response initiation rather than response selection. Psychonomic Bulletin & Review, 26, 29–47. https://doi.org/10.3758/s13423-018-1498-6 

Klein, G. A. (1993). A recognition-primed decision (RPD) model of rapid decision making. In G. A. Klein, J. Orasanu, R. Calderwood, & C. E. Zsambok (Eds.), Decision making in action: Models and methods (pp. 138–147). Ablex Publishing Corporation. 

Lewinski, W. J., & Hudson, W. B. (2003). Time to start shooting? Time to stop shooting? The Tempe study. The Police Marksman, 28(5), 26–29. 

Pashler, H. (1994). Dual-task interference in simple tasks: Data and theory. Psychological Bulletin, 116(2), 220–244. https://doi.org/10.1037/0033-2909.116.2.220 

Smith, M. L., & Boolani, A. (2024). Feasibility of a non-anticipatory, random-action target system to improve shooting performance: A brief field trial. Sports, 12(11), Article 305. https://doi.org/10.3390/sports12110305 

Zylberberg, A., Ouellette, B., Sigman, M., & Roelfsema, P. R. (2012). Decision making during the psychological refractory period. Current Biology, 22(19), 1795–1799. https://doi.org/10.1016/j.cub.2012.07.043