Trouble achieving goals? Why your brain needs reminders.

Many of us set goals, but sometimes we fail to achieve them. There is a way, though, to increase our chances of hitting our goals: Set reminders.

"It's quite hard to achieve our goals," said Sam Gilbert, professor of cognitive neuroscience at the University College London. "There are many, many reasons why we get led astray, or we don't manage to realize our goals."

One common, but addressable reason is that we simply forget them. Psychological studies suggest that 50 to 70 percent of our everyday memory failures involve forgetting our intentions.

Creating reminders can help address this problem. Research explains why.

Perhaps even without realizing it, many of us employ a psychological strategy called cognitive offloading, where we use a physical action to reduce demands on our brain. When we outsource our intentions from being stored just in our brains to somewhere outside our head - a notepad, Google Calendar or alerts on our smartphones - we are performing a specific kind of cognitive offloading known as intention offloading.

"It's fairly simple to implement. It's pretty ubiquitous," said Lauren Richmond, assistant professor of cognitive science at Stony Brook University. "People do things like this in the real world all the time, and it does seem to benefit performance at the end of the day."

Understanding the benefits - and potential pitfalls - of using cognitive offloading in our daily lives can improve our ability to remember and follow through with our intentions.

Instead of "changing the system inside your head, what cognitive offloading is trying to do is basically saying, 'you've got the capability, you've got a good memory, you've got a bad memory,'" Richmond said. "What we're trying to do is change the end result" so you can make that appointment or buy the right items from the grocery store.

"The biggest benefit is simply that we know that it improves memory performance," said Hunter Ball, assistant professor of psychology at the University of Texas at Arlington. "It increases the likelihood that you're going to remember to fulfill whatever goal it is that you need to fulfill."

In laboratory studies, participants performed better when they could use external reminders than when they could not.

Self-reported studies indicate older adults use external memory strategies, which could compensate for memory losses that come with aging, although more research needs to directly test how people use and benefit from reminders in the real world, Richmond said.

Using technology to outsource our intentions also frees up our finite cognitive resources.

Research has consistently shown storing information digitally produces a saving-enhanced memory effect, where we can better remember not only what we stored but also other information that was not saved.

The more we offload trivial information such as items on a shopping list, the more we can use our brain "for those more rarefied human cognitive tasks," such as creativity, Gilbert said.

We tend to offload information and create reminders when we think we need them, but not necessarily when we do need them.

Our beliefs about how good our memory is directly influence whether we supplement it. There is some indication that we tend to know how good our memory is and plan accordingly. Those who have a good memory but believe they don't, though, use more external reminders.

"It's absolutely crucial that we have an accurate understanding of our own memory ability," Gilbert said. "So if our understanding of our memory ability is wrong, this suggests that we will either overuse or underuse reminders."

Research indicates that humans have a tendency to be pessimistic about their fallible memory and may use more reminders than necessary. "That is a feature, not a bug," Gilbert said.

Our brains tend to avoid cognitive effort if we can, he said. This is beneficial "because the more that we remove the effort of one cognitive activity, the better that helps us to allocate that effort to a different cognitive activity," Gilbert said.

There are potential downsides to offloading our intentions. We may be more likely to forget them if we lose the reminder. If we trust the external storage, our brain does not devote the same resources to holding onto the information itself.

In one neuroimaging study of 15 participants, offloading intentions dampened activity in parts of the medial prefrontal cortex thought to encode the specific details of the task. Activity in the lateral prefrontal cortex, believed to track that something needs to be done, though, remained, indicating that the act of offloading diminishes our memory of the task itself but not that it needs to be done.

We are more likely to forget what we offloaded if we can no longer access our storage, such as when we misplace our notebook or our smartphone dies.

We also tend to offload the important things we most want to remember, one recent study by Gilbert and colleagues reported.

In 104 participants, offloading the high-value tasks also allowed them to remember more low-value tasks - a "cognitive spillover effect." In a surprise test, though, where their reminders were wiped clean, the participants were more likely to forget the important items and recall the unimportant ones.

Therein lies the irony: The more important the intention we want to remember, the more likely we are to offload it - and to forget it, if we lose our external memory store, Ball said.

"Awareness of the potential costs and deciding whether you're willing to accept those or not seems important and reasonable," Richmond said.

Consider the downsides of not using an external reminder, as well. "Of course, our phone battery dies, but how often does that actually happen versus how often does our own memory fail?" Ball said. "Our own memory ability, we forget things all the time."

The ubiquity of digital technologies has caused some people to worry that offloading our memories and intentions could be degrading our cognition over time, causing "digital amnesia" or "digital dementia."

Researchers are skeptical, however, about whether cognitive technology poses long-term harms, although nobody really knows because of the lack of longitudinal studies.

Worries about cognitive harm have spawned with each new technology, Gilbert said. Socrates argued that writing things down would cause us to become forgetful. "These fears are not in any way new," Gilbert said.

On the whole, "the benefits from offloading potentially far outweigh the cost of doing it," Ball said.