In safety investigations, findings of “human error” remain all too common. This framing risks oversimplifying complex incidents and obscuring modifiable contributors to risk.
Human error is rarely a cause. There is generally another why? and why is that? to be answered. What is termed human error is more commonly a predictable and normal outcome emerging from the interaction between cognitive capacity, task demands, environmental conditions, and system and work design - not a root cause.
Why “Human Error” Is an Incomplete Explanation
Human cognition is full of possibility, but it is not limitless. Attention fluctuates. Memory is fallible. Actions can fail to adjust to changing conditions. Judgement can be shaped by stress, fatigue, time pressure, and competing demands.
When safety investigations resolve to the identification of an individual contributor as root cause, this inherently informs a failure of the safety system of controls and may overlook:
- Excessive or persistent cognitive load
- Work-related fatigue and sleep disruption
- Poor information design or signal-to-noise imbalance
- Environmental stressors that impact attention, adaptive behaviours and decision-making
Human error in safety incidents may be reframed as brain–environment mismatches, rather than individual failures. Identifying this mismatch informs opportunities for improvement, re-design of systems of control and work design review.
Neuropsychology and the Roots of Error
You may be familiar with the term Human Factors. Neuropsychology can contribute to safety by examining the cognitive processes (with their bio-psycho-social underpinnings) involved in work performance, including:
- Sustained and divided attention
- Working memory and information integration
- Executive functions such as inhibiting automatic responses, planning and organising work, and judgement under pressure.
Lapses in these domains are predictable under certain conditions, particularly when demands exceed capacity. Safety control systems can be designed with consideration of these known limits of the human system.
A finding of human error prevents identification of modifiable contributors to an incident, or to risk. It is important to consider the individual factors in person-environment interactions to learn how we can improve the safety systems so the system doesn't fail in the face of normal human lapses. This enables proactive identification of risk factors before incidents occur. And the human and organizational performance principle is important: Blame fixes nothing.
Common cognitive risk contributors include:
- High task-switching requirements
- Dense or poorly prioritised information streams
- Prolonged vigilance demands without recovery
- Time or decision-making pressure combined with ambiguity
- Sensory overload or environmental distraction
These factors systematically increase the likelihood of attentional lapses and decision errors, regardless of experience or motivation.
Fatigue and Safety
Fatigue is one of the most significant yet underestimated safety risks. Fatigue impairs:
- Attention and vigilance
- Processing speed (speed of thinking)
- Error detection (situational awareness)
- Emotional regulation and risk appraisal
Importantly, individuals are often poor judges of their own cognition (Van Patten et. al., 2025), and this extends to fatigued individuals being poor judges of the impact of their fatigue on their abilities.
Situational Awareness and Signal Detection
Situational awareness is a skill. The implementation of that skill is shaped by workload, stress, fatigue, and environment.
Neuropsychological principles can enhance:
- Signal detection (distinguishing critical cues from background noise or distractors)
- Error monitoring, recognition and response
- Design of interfaces, notifications, and workflows that align with how attention works.
Well-designed systems do not rely upon perfect human performance. As highlighted earlier, a finding of human error inherently indicates a control system that has failed and has missed an opportunity for continual improvement.
Safer Systems, Not Better Humans
The goal of safety is not to eliminate human error, but to design systems that control for expected errors of the human (neuropsychological) system, and otherwise empower optimal human performance.
When work environments support attention, memory, and decision-making under real-world conditions, safety improves — not because people change, but because the systems supporting and empowering them do.
Neuro at Work series
This post forms part of a Neuro at Work series exploring how neuropsychological principles inform safer, more effective organisational systems. Future posts will examine leadership, decision-making, and recovery at work.
References:
Dehais, F., Hodgetts, H. M., Causse, M., Behrend, J., Durantin, G., & Tremblay, S. (2019). Momentary lapse of control: A cognitive continuum approach to understanding and mitigating perseveration in human error. Neuroscience & Biobehavioral Reviews, 100, 252-262.
Van Patten, R. Mulhauser, K., Austin, T. A., Bellone, J. A., Cotton, E., Chan, L., Twamley, E. W., Sawyer, K., & LaFrance Jr., W. C. (2025). The association between subjective and objective cognitive functioning from a transdiagnostic perspective: An umbrella review. Clinical Psychology Review. doi: 10.1016/j.cpr.2025.102648