Alternating attention is your ability to shift focus between two or more tasks that require different types of thinking. Rather than doing everything at once, you stop one task, switch to another, then return to the original without losing your place. It sits near the top of a five-level hierarchy of attention skills, meaning it’s one of the more complex cognitive abilities your brain performs.
Where It Fits in the Attention Hierarchy
Clinical psychologists Sohlberg and Mateer developed a widely used model that breaks attention into five levels, arranged from simplest to most demanding: focused attention, sustained attention, selective attention, alternating attention, and divided attention. Each level builds on the ones below it.
Focused attention is the most basic: simply noticing and responding to something in your environment. Sustained attention keeps you locked onto a task over time. Selective attention lets you filter out distractions and zero in on what matters. Alternating attention, the fourth level, adds the ability to deliberately shift between different sets of information or different tasks. At the top sits divided attention, which means handling two tasks truly simultaneously, like listening to a passenger while navigating traffic. The key distinction is that alternating attention involves switching back and forth, while divided attention means doing both things at the same time without pausing either one.
What It Looks Like in Everyday Life
You use alternating attention constantly, often without realizing it. Reading a recipe, stepping away to chop vegetables, then returning to the recipe to check the next step is a straightforward example. So is working on an assignment, answering a phone call, and then picking up the assignment where you left off. Driving requires it too: you shift your focus from the road ahead, to your mirrors, to the lane beside you, and back again in rapid succession.
Bilingual speakers rely on alternating attention in a particularly interesting way. Switching between languages mid-conversation requires the brain to disengage one language system and activate another, a process that exercises the same mental shifting ability measured in clinical attention tests. This is one reason bilingualism is often linked to stronger cognitive flexibility overall.
The Cost of Switching
Every time you shift between tasks, your brain pays a small toll. Researchers call this the “switch cost,” a measurable drop in speed and accuracy that occurs whenever you move from one task to another compared to staying with a single task. This penalty is nearly universal. People almost always take longer to complete a task and make more errors when switching than when they stay put.
Brain imaging studies confirm what the performance data shows. When people classify objects on different dimensions (color, shape, or pattern) and the classification rule changes from one trial to the next, their response times increase on the switch trials. The brain needs a moment to reconfigure itself, loading new rules and suppressing the old ones. Interestingly, people who are heavy media multitaskers, those who habitually bounce between screens, apps, and streams of content, tend to show larger switch costs than lighter multitaskers. Frequent switching doesn’t necessarily make you better at it.
How the Brain Manages the Shift
Alternating attention depends on a large network of brain regions working together. Dorsal parietal areas (near the top and back of your head) and frontal regions (behind your forehead) coordinate the focus of spatial, object-based, and feature-based attention. Subcortical structures deeper in the brain help integrate information across these areas.
One structure that may play a surprising supervisory role is the hippocampus, typically associated with memory. Recent work suggests the hippocampus alternates between processing external information (what’s happening around you) and internal information (memories, plans, mental models) by dynamically shifting which of its local circuits gets priority. In other words, one of the brain’s memory centers may also act as a switchboard for attention.
How Alternating Attention Is Tested
The most common clinical tool for measuring this ability is Part B of the Trail Making Test. You’re given a sheet of paper with circled numbers and letters scattered across it. Your job is to draw a line connecting them in alternating order: 1, A, 2, B, 3, C, and so on. The task forces you to switch between two mental sets (numbers and letters) while keeping track of where you are in each sequence.
Part A of the same test, which only involves connecting numbers in order, provides a baseline for motor speed and visual search. Comparing your Part B time to your Part A time isolates the cognitive cost of shifting. In a study of older adults with a mean age of about 76, the average Part B completion time was roughly 98 seconds. Faster completion consistently correlated with better performance on other cognitive tests across multiple domains, reinforcing that task-switching ability is a reliable marker of overall cognitive health.
What Happens When It Breaks Down
Impaired alternating attention shows up in several clinical populations. After a traumatic brain injury, many people struggle to shift between tasks smoothly. They may get “stuck” on one activity, unable to disengage and redirect their focus. Simple things like pausing a conversation to answer the door and then resuming the conversation can become genuinely difficult.
Children with ADHD also show weaknesses in this area, and the picture gets worse when ADHD and brain injury overlap. Research from Johns Hopkins found that children with both severe traumatic brain injury and ADHD performed significantly worse on measures of attention, executive functioning, and memory compared to children with brain injury alone. The combination compounds the difficulty, making task-switching and mental flexibility especially challenging for this group.
In daily life, impaired alternating attention can look like losing your train of thought whenever you’re interrupted, struggling to return to a task after a distraction, or feeling overwhelmed when responsibilities require frequent shifting. It’s one of the reasons brain injury rehabilitation places heavy emphasis on attention retraining.
Training and Rehabilitation
For people recovering from brain injury or managing attention deficits, several evidence-based approaches can help rebuild alternating attention. The American Congress of Rehabilitation Medicine recommends direct attention training combined with metacognitive strategy training, which means both practicing the skill itself and learning strategies to compensate when it falters.
Attention Process Training (APT-III), a computerized program developed by Sohlberg and Mateer, targets each of the five attention levels with specific exercises. It carries a moderate level of evidence for effectiveness. Dual-task training, where you practice doing two things that compete for your attention, has strong evidence for improving dual-tasking ability on similar tasks. Time pressure management is another well-supported approach. It teaches structured problem-solving strategies for coping with mental slowness, helping people handle situations where they need to process and shift quickly.
Working memory exercises like the N-back task, where you’re shown a sequence of numbers and asked to recall what appeared a certain number of steps back, also support attention by strengthening the executive components of working memory. Computer-based cognitive programs can be useful as a supplement, but expert guidelines caution against relying on them alone. Repetitive, decontextualized computer drills without therapist involvement aren’t recommended. The most effective training ties exercises to real-world functional activities, practicing attention skills in the context of cooking, organizing, or managing a schedule rather than in abstract isolation.
For people without clinical impairments who simply want sharper task-switching, the practical takeaway from the research is straightforward: minimize unnecessary switching when you can (since every switch carries a cost), but practice deliberate, structured switching when the situation demands it. Your brain can get more efficient at transitions, but it will never eliminate the cost entirely.