NEW YORK (NYTIMES) - As we age, our memory declines. This is an ingrained assumption for many of us.

However, according to neuroscientist Richard Restak, a neurologist and clinical professor at George Washington Hospital University School of Medicine and Health, decline is not inevitable.

The author of more than 20 books on the mind, Dr Restak has decades' worth of experience in guiding patients with memory problems.

His latest book, The Complete Guide To Memory: The Science Of Strengthening Your Mind, includes tools such as mental exercises, sleep habits and diet that can help boost memory.

"The point of the book is to overcome the everyday problems of memory," he said.

This is especially for working memory, which falls between immediate recall and long-term memory, and is tied to intelligence, concentration and achievement.

According to Dr Restak, this is the most critical type of memory and exercises to strengthen it should be practised daily. But bolstering all memory skills, he added, is key to warding off later memory issues.

Memory decline is not inevitable with ageing, he argues in the book. Instead, he points to 10 "sins" or "stumbling blocks that can lead to lost or distorted memories".

Seven were first described by psychologist and memory specialist Daniel Lawrence Schacter: "sins of omission", such as absent-mindedness, and "sins of commission", such as distorted memories. To those, Dr Restak added three of his own: technological distortion, technological distraction and depression.

Ultimately, "we are what we can remember", he said. Here are some of his tips for developing and maintaining a healthy memory.

Pay more attention

Some memory lapses are actually attention problems, not memory problems.

For instance, if you have forgotten the name of someone you met at a cocktail party, it could be because you were talking with several people at the time and did not properly pay attention when you heard it.

"Inattention is the biggest cause for memory difficulties," Dr Restak said. "It means you didn't properly encode the memory."

One way to pay attention when you learn new information, such as a name, is to visualise the word.

Having a picture associated with the word, Dr Restak said, can improve recall. For instance, he recently had to memorise the name of a doctor, Dr King - an easy example, he acknowledged. So, he pictured a male doctor "in a white coat with a crown on his head and a sceptre instead of a stethoscope in his hand".

Find regular everyday memory challenges

There are many memory exercises that you can integrate into everyday life.

Dr Restak suggested composing a grocery list and memorising it. When you get to the store, do not automatically pull out your list or your phone - instead, pick up everything according to your memory.

"Try to see the items in your mind," he said. Consult the list only at the end, if necessary. If you are not going to the store, try memorising a recipe - frequent cooking is actually a great way to improve working memory.

Play games

Games such as bridge and chess are great for memory, but so is a simpler game, said Dr Restak. For instance, his favourite working memory game is 20 Questions - in which a group or a single person thinks of a person, place or object, and the questioner asks 20 questions with a yes-or-no answer.

To succeed, he said, the questioner must hold all of the previous answers in his or her memory in order to guess the correct answer.

Another of Dr Restak's tried-and-true memory exercises simply requires a pen and paper or audio recorder.

First, he says, recall all of the United States presidents, starting with President Joe Biden and going back to, say, Franklin D. Roosevelt, writing or recording them. Then, do the same, from FDR to Mr Biden. Next, name only the Democratic presidents and only the Republican ones. Last, name them in alphabetical order.

If you prefer, try it with players on your favourite sports team or authors. The point is to engage your working memory, "maintaining information and moving it around in your mind", he wrote.

Read more novels

One early indicator of memory issues, according to Dr Restak, is giving up on fiction. "People, when they begin to have memory difficulties, tend to switch to reading non-fiction," he said.

Over his decades of treating patients, he has noticed that fiction requires active engagement with the text, starting at the beginning and working through to the end. "You have to remember what the character did on Page 3 by the time you get to Page 11," he added.

Beware of technology

Among Dr Restak's three new sins of memory, two are associated with technology.

First is what he calls "technological distortion". Storing everything on your phone means that "you don't know it", he said, which can erode one's mental abilities.

"Why bother to focus, concentrate and apply effort to visualise something when a cell phone camera can do all the work for you?" he wrote.

The second way our relationship with technology is detrimental to memory is because it often takes our focus away from the task at hand.

"In our day, the greatest impediment of memory is distraction," he wrote. Many of these tools have been designed with the aim of getting the user addicted and, as a result, people are often distracted by them. People can check their e-mail while streaming Netflix, talking to a friend or walking down the street.

All of this impedes our ability to focus on the present moment, which is critical for encoding memories.

Work with a mental health professional

Your mood plays a big role in what you do or do not remember.

Depression, for instance, can greatly decrease memory. Among "people who are referred to neurologists for memory issues, one of the biggest causes is depression", Dr Restak said.

Your emotional state affects the kind of memories you recall. According to Dr Restak, the hippocampus, or "memory entry centre", and the amygdala, the part of the brain that manages emotions and emotional behaviour, are linked.

"When you're in a bad mood, or depressed, you tend to remember sad things," he said. Treating depression - either chemically or via psychotherapy - also often restores memory.

Determine whether there is cause for concern

Not all memory lapses are problematic. For instance, not remembering where you parked your car in a crowded carpark is normal. Forgetting how you arrived at the carpark space in the first place, however, indicates potential memory issues.

There is no simple solution to knowing what should be of concern, Dr Restak said. Much of it is context-dependent. For instance, it is normal to forget the room number of your hotel, but not the address of your apartment. If you are concerned, it is best to consult a medical expert.