Cognitive Load Theory has emerged as a pivotal framework for understanding the complexities of studying and knowledge processing. By examining how the human mind manages cognitive sources, educators and learners alike can improve educational outcomes through knowledgeable research techniques. High intrinsic cognitive load happens when the material is complicated, making it challenging for learners to retain info.
After reading a subject, explain it aloud or in writing – even if it’s simply to yourself. “Teaching” an idea strengthens schemas and highlights areas that need more consideration. Combine words and visuals – add diagrams, sketches, or thoughts maps alongside textual content. Dual coding engages each verbal and visible pathways, doubling the routes to recall. Learners can even take steps to mitigate these points by being conscious of their environment and minimizing distractions whereas finding out.
Surveys such because the NASA Task Load Index (NASA-TLX) permit educators to measure perceived workload. The Cognitive Load Scale (CLS) is another tool that quantifies cognitive load during studying actions. Eye-tracking know-how can provide insights into cognitive processing during duties. Additionally, educational software with built-in analytics can monitor pupil engagement and efficiency.
Continuing training accreditors should modify to this new actuality and supply micro-credits. Learning organizations are already adjusting and offering nano-degrees. The greatest means to do that is to attach with someone on an emotional degree.
When groups are homogeneous, novices are involved in cognitively demanding search-based drawback fixing. When they are educated learners, homogeneity could additionally be of no profit since these learners can most likely take care of the problems using their obtainable knowledge base. In common, the outcomes confirmed this; however, they also found that when participants have relevant task data, individual learners marginally outperform homogeneous and heterogeneous groups. With respect to cognitive load, if learners have related knowledge to carry out a task, communication and coordination actions could also be pointless and even detrimental to studying.
This optimal functioning aids in memory improvement, as working memory serves because the workspace where info is actively processed and integrated with present knowledge. Chunking information refers back to the means of breaking down massive amounts of information into smaller, manageable units or “chunks.” This cognitive technique enhances reminiscence retention and facilitates easier retrieval of information. By organizing material into coherent groups, people can significantly scale back their cognitive load. Multimodal learning environments point out complicated necessities for future growth.
Cognitive Load Theory suggests managing intrinsic load by breaking down complicated info into easier elements and constructing on existing data. Alan Baddeley’s mannequin of working reminiscence expanded on earlier ideas by introducing the idea of multiple elements inside working reminiscence, together with the phonological loop, the visuospatial sketchpad, and the central executive. George Miller’s seminal work, “The Magical Number Seven, Plus or Minus Two,” explored the boundaries of human short-term reminiscence capability. He found that people might only maintain about seven objects in their working reminiscence at a time. This concept of restricted working memory capacity immediately influenced Sweller’s understanding of cognitive load, highlighting the want to manage data presentation to keep away from overloading learners. Studies within the cognitive load field predominantly use a between-subjects design.
People need connection however really feel stretched by time, emotional labor, and unresolved issues. When you add monetary pressure or co-parenting complexities, the stress turns into even heavier. Jogging, swimming, and even strolling can increase endorphins, the physique’s pure stress relievers. Students could want to purpose for no less than half-hour of average train most days of the week. Move toward private transformation that frees you from a few of that psychological burden.
By doing so, people can mitigate the unfavorable influence of crises on their mental well being and foster resilience. Crisis administration is a vital facet of maintaining psychological wellness, notably in periods of intense stress or uncertainty. Effective disaster management enables people to navigate difficult conditions, mitigate potential harm, and foster resilience.
The amygdala facilitates the formation of stimulus associations and helps to establish the emotional which means of various situations 70. However, within the learning process, classification utilizing the phrases “positive”, “negative”, and related terms appear to be extra appropriate. Therefore, adverse emotions have an effect on well-being and provoke a want to keep away from or evade.
To conclude, with the change in academic paradigms and enhance in distance studying, educators need to concentrate to working reminiscence and thesummative cognitive load imposed in it. The summative load, which is a mixture of intrinsic and extrinsic parts, could be made tolerableif scaffolding of the instructional designs is finished. Germane load refers back to the mental effort required to process info and relate it to present information.
Ultimately, addressing these challenges calls for a nuanced method that considers content material design, technological constraints, and learner range to optimize cognitive load management in online studying environments. Analytics also play an important position in ongoing cognitive load administration. Learning administration techniques can collect in depth knowledge on person interactions, serving to designers refine content and delivery strategies.
By using visuals, you not only simplify the training course of but in addition enhance germane load, facilitating higher understanding and retention. After all, if the mixture of ICL and ECL is comparatively excessive, further GCL could end in cognitive overload. However, when that state of cognitive overload is reached depends on the boundaries of the individual learner’s working reminiscence and, obviously, motivation to take a position a sure effort within the first place. In the two-factor mannequin, the place GCL is a half of ICL, the entire cognitive load is decrease than the entire cognitive load within the three-factor model until a learner experiences zero GCL. In different words, within the case of a comparatively excessive combination of ICL and ECL, cognitive overload should be barely much less doubtless within the two-factor than in the three-factor model.
Intrinsic load refers back to the required cognitive assets it takes to complete a studying task. Intrinsic learning tasks differ in complexity and interactivity with different parts inside the learning environment. As such, understanding the complexity of the task and the learner will help determine how many cognitive assets might be utilized in any learning task. Intrinsic load should be managed by trying to simplify complicated materials to create more capability for germane load.
This load is useful for studying, as it encourages deeper understanding and retention. Techniques similar to scaffolded learning and lively engagement can improve germane load, promoting effective studying outcomes. The implications of cognitive load lengthen into numerous features of education. For occasion, tutorial design may be enhanced, permitting for tailored approaches that decrease distractions and focus consideration on important content. Students are extra probably to succeed when studying experiences are carefully structured.
This analysis reinforces the critical function of AI and ML in enhancing studying experiences in high cognitive load domains, providing a data-driven roadmap for continued developments in AI-based training. The findings from this analysis question reveal a posh framework via which AI-powered AL techniques optimize cognitive load, considering individual variations among learners. Synthesized evidence reveals that AI-driven mechanisms enhance personalization, improve studying efficiency, and maintain engagement. These mechanisms include real-time monitoring, dynamic difficulty adjustment, adaptive feedback, and multimodal knowledge integration.
Despite these issues, cognitive load theory remains a priceless framework for understanding and enhancing studying. Whilst measuring cognitive load is challenging, contemplating it’s a essential facet of efficient learning experience design. Approaching the rules of Cognitive Load Theory inside tutorial design entails a strategic focus on how material is offered.
Extraneous cognitive load refers again to the pointless psychological effort that detracts from learning. It’s like having too much clutter in your thoughts while making an attempt to give attention to important data. When our brains are overloaded with irrelevant particulars, it becomes tougher to grasp and remember what we’re studying. Managing cognitive overload entails taking proactive steps to minimize back mental strain. Start by organizing and prioritizing tasks to give attention to what’s most important. Take common breaks, set clear boundaries, and reduce distractions—such as silencing notifications or creating a delegated workspace.
When you’re confronted with a endless to-do list, breaking tasks down into smaller, more manageable chunks could be incredibly useful. Instead of thinking about “cleaning the home,” strive focusing on specific tasks like vacuuming the lounge or organizing the toys. Many individuals find themselves fighting the sheer volume of tasks and the sensation of not having adequate assist. In the meantime, the experts supply ways to lighten the burden of the mental load at house. But the psychological load could additionally be worse than it’s ever been as societal expectations and pressures have elevated. There’s a rising price of kid care and college tuition, tech and social media considerations, college violence, and experiencing a pandemic that turned lives upside down.
Keep your workspace tidy, turn off notifications in your phone, and eliminate pointless distractions. This might help scale back extraneous cognitive load and allow you to focus your psychological power on the task at hand. By using these measurement strategies, educators and instructional designers can fine-tune their approaches to reduce extraneous cognitive load.
There are, nonetheless, indications that the sensitivity of this measure to workload adjustments diminishes with age of the members (van Gerven et al. 2004). Cognitive load can also be assessed by using neuro-imaging strategies. Though it is a promising area (see e.g., Gerlic and Jausovec 1999; Murata 2005; Smith and Jonides 1997; Volke et al. 1999) there are still questions on the way to relate mind activations exactly to cognitive load. Overall, physiological measures present promise for assessing cognitive load but (still) have the disadvantage of being quite intrusive. Merriam-Webster’s on-line dictionary defines effort as “the whole work carried out to achieve a specific end” and load as “the demand on the operating assets of a system”.
This can lead to the next cognitive workload as they try to course of info and make selections rapidly. Additionally, cognitive load, as mentioned earlier, refers again to the mental sources wanted to course of and comprehend information. Tasks that require individuals to process complex or unfamiliar information could lead to a better cognitive load. Ultimately, understanding the influence of distractions on studying outcomes is essential for educators to devise strategies that foster sustained attention and optimize studying in both conventional and on-line settings.
For example, when college students create a timeline of Art History movements, they’ve to attach individual facts to the larger and broader historic context, and such activities can type a robust schema (Stern, 2019). Taking time away from educating to reduce back students’ anxiousness by engineering alternatives for fulfillment and reflection is more probably to be worthwhile and an effective use of lesson time in the long run. Read about cognitive overload for extra data on how and why cognitive overload occurs, and what lecturers can do in the classroom to avoid this.
Understanding the interaction between working memory and cognitive load is important for creating effective learning strategies. As cognitive load management strategies refine the calls for placed on working reminiscence, they facilitate higher retention and understanding, ultimately bolstering reminiscence enchancment efforts. Allocating various durations for study classes optimally aligns cognitive processing with individual studying types. This method allows for adequate breaks, that are necessary for psychological restoration and information absorption. By integrating effective timing and spacing strategies, learners can significantly enhance their reminiscence capabilities, thereby managing cognitive load more effectively.
Research suggests that our working memory has restricted capacity—typically processing about 4 to 7 components at a time. When complicated studying is introduced by way of a selection of channels it makes it a lot easier for learners to understand. Each presentation of the information via totally different channels acts as both apply and taps into a special cognitive load, extra evenly distributing the said load. In the subsequent section we are going to discover extra in depth what a schema is and why its significance.
Often, therapists can assist anyone who desires instruments, assets, and extra tips to handle life’s on an everyday basis struggles. An skilled therapist may train you essential coping expertise to manage your college workload, other actions, and private life. Effective tutorial design requires aligning content richness with the learners’ prior information, cognitive capacities, and general course aims. Richer content material must be integrated thoughtfully, utilizing clear buildings, visual aids, and manageable segments.
These involve utilizing fancy devices to observe things like eye movements, heart rate variability, and even mind exercise. It’s like being a cognitive detective, looking for clues in the body’s responses to mental effort. Cognitive neuroscience has been instrumental in developing these methods, bridging the hole between psychology and brain science. This is fairly straightforward – the more complex or tough a task is, the higher the cognitive load. It’s the distinction between including 2 2 and fixing a differential equation.
And for researchers, there remain exciting frontiers to discover in our quest to unlock the full potential of human learning. As academic know-how evolves, we want to higher understand how completely different digital instruments and environments impact cognitive load and schema formation. This contains exploring the consequences of digital and augmented actuality, synthetic intelligence, and other emerging applied sciences on studying processes. This limitation is essential because working reminiscence is where all our acutely aware cognitive processing occurs. It’s the site of consciousness and thinking, the psychological stage where we manipulate data, solve issues, and assemble understanding. Given these constraints, CLT posits that efficient studying happens after we can efficiently transfer info from working memory to long-term memory with out overwhelming our cognitive assets.
By incorporating these strategies into your learning routine, you’ll find a way to considerably scale back cognitive load and improve your capacity to absorb and retain new information. Extraneous cognitive load, on the opposite hand, is brought on by poor educational design or presentation. It’s like attempting to drink from a firehose – too much information is offered at once, overwhelming the learner with no clear direction.
This approach minimizes extraneous load whereas maintaining an enticing learning expertise. Balancing cognitive load with content richness includes guaranteeing that on-line learning supplies present sufficient depth to facilitate meaningful understanding with out overwhelming learners. Too much content material complexity can increase intrinsic and germane hundreds, hindering efficient learning. Conversely, overly simplified content could fail to have interaction or problem learners appropriately.
Personalization in studying can even profit from Cognitive Load Theory. Adaptive studying applied sciences that tailor content to particular person student’s strengths and weaknesses can facilitate deeper engagement and promote higher memory retention. The World Health Organization defines stress as a pure response to tough situations, and the WHO notes that everyone experiences stress in their lives at some point.
The time period “mental load” is a useful shorthand, and discovering it typically makes mums in particular feel seen and understood in a new means. Meanwhile, new or unfamiliar data can improve cognitive load as your mind tries to make sense of it. Lastly, our working memory, which holds information temporarily, has restricted capability. This may also promote learner engagement which is important as learners must nonetheless select to deliberately interact with the fabric and develop new schemata. Have you struggled to focus during drills or forgotten a play you just learned?
As their instructor, I noticed development in my students’ total confidence and emotional regulation, together with the event of metacognitive abilities. As they developed these expertise, they started to use the strategy card to prioritize and make a plan, which helped them with the power to initiate tasks as properly. Additionally, I noticed a lower in procrastination and missed assignments. My college students reported that they noticed a greater understanding of what their brain could and couldn’t deal with, and developed information of the methods they might use in the event that they entered Zone three. It is essential to acknowledge that technological constraints—such as limited bandwidth, gadget incompatibilities, and software program glitches—can impede efficient studying. Educators and designers should choose sturdy, scalable platforms which would possibly be adaptable to totally different technological contexts, decreasing obstacles to engagement.
You’ve learned how to identify excessive cognitive load by searching for components such as info overload, advanced instructions, and inadequate support. You also know the means to measure its impression utilizing metrics like task completion charges, learner satisfaction, and information retention. By acknowledging the limitations of human working memory, you can implement strategies to scale back cognitive load. Another essential side is to make certain that studying materials are optimized for different devices and internet connections. This would possibly contain compressing information, using responsive design elements, or providing alternative formats for content material.
This involves providing assist to learners and gradually removing it as they turn out to be more adept. It’s like teaching someone to experience a motorcycle – you start with coaching wheels and finally take them off. Without a doubt, we live in an information-rich world the place it’s extremely straightforward to feel mentally overloaded. Start by constructing a space where students feel safe sufficient to ask questions, share ideas, and admit moments of confusion. For instance, in a historical past class, you may present a immediate like “What had been the potential motivations behind a historic event? ” Students first mirror on their response, then talk about it with a associate before sharing with the group.
Instructors want materials to be adequately difficult, but not so challenging that deep connections to the educational are unable to take place. For example, consider elementary faculty students studying the means to write a five-paragraph essay. Having college students write all 5 paragraphs directly without managing the processes can be extraordinarily difficult. Simplifying the fabric to a paragraph that has scaffolded sentences that concentrate on subject sentences, supporting ideas, or a thesis breaks the content material into manageable chunks. The course of is simplified when first learning about essay writing, however instructors know that a high schooler could probably be given a topic and advised to put in writing a five-paragraph essay with considerably less scaffolding.
Understanding these measurement techniques is integral for educators and instructional designers aiming to optimize learning environments and enhance academic outcomes through effective cognitive load administration. Finally, fostering a supportive studying environment encourages engagement whereas minimizing extraneous load. To reduce extraneous cognitive load in on-line instructional design, readability and simplicity are paramount. Streamlining content material by removing irrelevant data helps learners give consideration to important material with out pointless distractions.
In short, emotional “check-in” is an easy but effective follow for a greater reference to yourself and a finer management of the psychological load. The thought is to not change your emotions, but to turn into aware of their presence and impact. By cultivating this emotional consciousness, you’ll be better outfitted to grasp how your emotions have an effect on your mental load.
Teachers get caught in a vicious cycle of spinning their wheels, planning one week after one other and watching as some lessons succeed whereas others fail. The discussion paper by Scheiter (2025) supplies a critical reflection on contributions within this topical assortment, addressing the theoretical and empirical challenges that merging CLT and SRL principle brings. As a needed subsequent step, Scheiter emphasizes the need for a extra unified method that integrates cognitive and motivational theories.
Too usually, cognitive overload prevents the true capabilities of competent students from shining via. They know and perceive the content being taught, but they’ve difficulty demonstrating their mastery of the material. I teach all of my college students, including those with ADD or ADHD, how to acknowledge and handle cognitive overload as a needed life talent. Cognitive load concept suggests that educators remove competing stimuli so as to avoid the split-attention impact, and may enable students to concentrate on a single visual source of data at any given time.
If you are managing your workload in this way however are nonetheless working exterior of your contracted hours, you’re most likely trying to do too much. Consistent work overload may cause high ranges of stress, leading to exhaustion and eventually burnout. More than half (56%) of accountants endure from burnout, and work overload is a recognized cause. Platforms like Teachers Pay Teachers, Khan Academy, and Padlet provide valuable assets, saving time and improving teaching high quality. Teachers would possibly share issues with administrators, looking for solutions collaboratively.
And should you add carefully chosen dietary supplements, you may acquire a bit extra resilience and clarity. Now that we’ve explored the complexities of cognitive load, let’s summarize the important thing takeaways from our journey through its impact on studying. Let’s wrap up by distilling the principle insights into actionable recommendation. Avoid utilizing jargon or overly technical terms that will confuse learners.
One helpful idea that can serve as a basis for these strategies is cognitive load concept. Similarly, when learning new info, breaking it down into smaller, more manageable chunks might help your mind process it more efficiently. This is as a result of our working memory, which holds info briefly, has limited capability. By chunking data, you reduce the cognitive load in your working memory and make it easier to remember and understand. When the intrinsic and extraneous masses are balanced, we will obtain optimum cognitive load, resulting in efficient studying. How does cognitive load management increase your learning and performance?
It helps them comprehend the nuanced and varied components affecting learning, both internally and externally. By understanding cognitive loads and the methods that influence them, lecturers can create learning experiences that balance intrinsic, extrinsic, and germane loads to create optimized studying for all their students. Cognitive load is a important factor in studying and decision-making processes. Understanding the several sorts of cognitive load and the way to handle them is essential to optimize mental illustration and enhance performance. By reducing extraneous cognitive load, managing intrinsic cognitive load, and optimizing germane cognitive load, individuals can improve their learning outcomes and make better decisions. One important software is in educational design, which makes use of insights from cognitive load concept to create supplies that decrease extraneous load.
This structured approach allows your thoughts to refresh and reduces the ongoing psychological burden. Begin the method of lowering extraneous load by simplifying instructions.. The finest method to decrease extrinsic load, or to place it one other means – distractions within the surroundings that divert student attention – is on your students to focus in on what’s on the heart of the lesson, the intrinsic load.. Teachers who don’t have a real understanding of intrinsic load are vulnerable to overloading their students with instruction that is too complicated, nor matched to their college students level of need. When our tiny tables turn into overloaded with parcels (new information), learning will inevitably break down.
This might be coming from the design of the task, the surroundings where instruction is delivered, or other components that are not directly associated to the task. (Like children yelling within the background, development noise, or information alerts.) As we all know, even if the duty is simple, distractions coming from outside might make it hard to study. Some tasks are harder to complete than others—cognitive load concept states that these tasks increase the calls for on our workers.
Waldeyer et al. (2024) report two experiments examining how cue directions have an result on learners’ self-assessment accuracy throughout problem-solving duties. Only when mixed with both particular cue criteria instructions and self-explanation prompts, explanation-based cues yielded comparable levels of self-assessment accuracy as performance-based cues. The authors conclude that it’s more environment friendly to immediate learners to watch performance-based somewhat than explanation-based cues in the preliminary problem-solving part.
For instance, utilizing diagrams in a biology class can link earlier classes with new content on ecosystems. Lastly, Coursebox has many interactive elements, such as quizzes, dialogue boards, and gamified activities. Instructors can use this to promote germane load and encourage learners to actively have interaction with the material. However, intrinsic load is unavoidable because it is dependent upon the task itself.
Building on the second point, our third point revolves round circumstances where perceived effort does not seem to affect effort regulation, or where perceptions of effort are silenced. As the study by Abel et al. (2024) shows, what looks as if a misinterpretation of effort may instead mirror a knowledge gap or false impression about effective studying. Similarly, high-stakes contexts or extremely important objectives may lead learners to suppress or ignore effort perceptions. Broadening the scope of research to such contexts will shed light on when to take perceived effort into the equation and when to spend instructional help elsewhere. Providing the conditional knowledge that interleaving methods highlight variations didn’t have an result on the use of interleaving, suggesting that learners were already aware of this.
This can mean dealing with a badly formatted textbook with font that is too small, taking a glance at chaotic overloaded lecture slides, or jumping backwards and forwards between completely different learning media. Educate yourself concerning the psychological and physical health resources obtainable at your child’s new school. Communicate together with your youngster about how folks like school counselors can be helpful resources through the college day (Bring Change to Mind).
Designers can see how AI capabilities can present labored examples or scaffolds to reduce intrinsic load for learners. To evaluation the key concepts of this chapter please watch the video abstract. Effective on-line learning may be significantly enhanced by applying Cognitive Load Theory. This method advocates for minimizing extraneous cognitive load while maximizing germane cognitive load, leading to improved learning outcomes. By understanding how cognitive load influences students’ psychological processes, educators can create simpler on-line learning environments. Understanding these three forms of cognitive load is essential for educators and instructional designers.
If you’re experiencing grief, loneliness, holiday despair, or family stress during the winter season, you’re not alone. “A massive cause mental well being declines in December is as a end result of the nervous system gets pulled in many instructions without delay,” Bean explains. Among the restrictions of this research was including only English language articles which signifies that missing some research is feasible. It was also limitation related to the uncertainty of the standard of articles.
Automated metrics can provide prompt feedback, enabling educational designers to refine digital environments constantly. This data-driven strategy ensures that cognitive load management methods evolve alongside learners’ wants. Emotional instability and stress are the principle disturbances that situation the training process, affecting each academics and college students. The primary objective of this review is to analyze the affect of stress and feelings (as part of stress) on the learning setting. Stress is a physiological mechanism that the organism develops to adapt and survive external and internal challenges.
For example, classes may incorporate gaming elements corresponding to badges, leaderboards, level systems, simulations, challenges, strategy development, and competitors to make learning interactive and fun. Once we now have the bookshelves (framework) we are in a position to start filling them with books (new information). It’s like adding a guide to a labeled and arranged shelf within the library and very related to a well-organized bookshelf, these schemas allow you to to retrieve information and data rapidly and efficiently.
In processing new info, WM retrieves and reactivates matching cognitive schemas from LTM to encode the data (Squire and Dede, 2015; Norris, 2017). The more usually a schema is activated, modified, and efficiently applied, the sooner new information is encoded, parceled, and forwarded to and from LTM (Sporer, 2016; Fernández et al., 2017). Therefore, the method of schema automation and schema development are, according to CLT, the key steps within the means of studying (Van Merriënboer and Sweller, 2010).
The similar goes for our brains after we strive to take in an extreme amount of information at once. In our increasingly complex world, lowering cognitive complexity has turn into a crucial ability. “Yes, it’s true, initially, teaching somebody would possibly demand further work. It may look like you’re piling more onto your plate, however let’s think about a unique viewpoint. Although it could be more work initially, once the duty or skill is mastered, that’s one thing that might be eliminated from your to-do listing.
John Sweller and a lot of other cognitive load theorists proceed to analysis reminiscence and how learning may be modulated by elements of the environment, human movement, and different influences (Paas, 2020). Sweller emphasizes that educational design ought to take into account the role and limitations of working reminiscence, and he even developed a computational mannequin to assist his claims. Cognitive load optimization entails adjusting the quantity of knowledge introduced to learners.
Incorporating mental health days into the college calendar may be preventive. The World Health Organization (WHO) emphasizes the significance of mental well being days in preventing burnout and selling long-term wellness. Connecting with colleagues fosters camaraderie and provides emotional assist. Utilizing platforms like social media groups, skilled forums, and even casual meetups can strengthen this community.
Alternatively, you can use microlearning, which is designed to reduce learner fatigue. It implies spending lower than 20 minutes focusing on one studying objective. newlineYou’d principally interact with content in short bursts, and this might help you keep the model new materials more simply. Multitasking could really feel productive, nevertheless it truly fragments consideration and increases psychological fatigue. Every time you turn tasks, your brain incurs a switching price, that means a brief period where neither task is being accomplished efficiently. In the lengthy run, multitasking will increase psychological fatigue, results in poor productivity, and is commonly the cause for burnout. By pairing these methods with habits that support cognitive power – rest, motion, vitamin, focus – you rework examine time from wrestle into sustainable skill-building.
Women who incorporate small every day pleasure rituals usually report improved consolation, lubrication, and desire over time. At Proactive For Her, our care plans blend physical, emotional, and relationship tools so ladies can rebuild libido with out overwhelm. It can present a psychological distraction, lessen muscle tension and decrease stress hormones. These might embody ingesting too much caffeine or alcohol, smoking, eating an extreme quantity of, or using unlawful substances.