Since I’m too obsessive for my own good, and one of the most sceptical people I know, Mind Focus is not a collection of features chosen at random, but rather a reflection of my neurosis for applying what has been shown to work according to data and what has also worked for me personally.

That’s why every element of the app (the background noises, the breathing techniques, the attention exercises, the tones…) has real science behind it.

And I think it’s worth explaining what lies beneath the surface of the app, how it works and, above all, why it does what it does.

Let’s start with the main thing.

The science behind isochronic tones

I chose them not only because they worked better for me than other options, but also because science also seems to confirm that in general terms.

And while I do enjoy the sound of my own voice, I don’t want to repeat myself too much. So if you want to go deeper into this specific aspect of Mind Focus’ isochronic tones (and why their implementation in the app is more effective than in other alternatives that also use them), you can take a look at the articles I’ve written covering them in depth.

That way I won’t turn this text into another Lord of the Rings:

• What isochronic tones are (and why they work according to science).
• The difference between isochronic tones and binaural beats (and why I chose the former).

Brown noise and pink noise

As a companion to the tones, the app also generates two types of background noise, brown and pink, which are used in different parts of the application (and can easily be turned on or off to the user’s liking).

Again, this choice is not an aesthetic whim. These are the types of abstract noise that have shown the most effectiveness for what we seek here.

Thus, Lu et al. (2020) studied the effect of noise colour on the cognitive performance of 22 participants. Pink noise was the only one that significantly improved performance on sustained continuous attention. Meanwhile, both brown and pink showed improvements in working memory.

Silence and white noise did not produce the same effects.

The meta-analysis by Nigg et al. (2024), published in the Journal of the American Academy of Child & Adolescent Psychiatry and focused on ADHD, found positive effects of pink noise on cognitive performance.

The review by Zhou et al. (2012), with EEG and sleep study, further showed that pink noise synchronises brain activity with the external stimulus and significantly improves sleep quality.

The probable mechanism is the masking of unpredictable external distractions and the background synchronisation of neural activity, creating an auditory environment that the brain can easily ignore and that, at the same time, reduces random stimulation peaks.

The physiological sigh

The section «One minute Reset» in Mind Focus uses the physiological sigh, a breathing technique that consists of a double nasal inhalation followed by a slow exhalation through the mouth.

The first breath is deep, filling the lungs, and the second is much shorter, barely an additional sigh that draws a little more air into those already full lungs. The mouth exhalation is longer and is usually done with lips pursed, as if you were blowing through a straw.

Although the technique was popularised some time ago by neurobiologist Andrew Huberman, he did not create it and it already had science behind it supporting its effectiveness.

Li et al. (2016) published in Nature the identification of the neural circuit that controls the sigh. It involves around 200 specific neurons in the brainstem that activate differently. Sighs are physiologically distinct from normal breathing, and they’re not simply «deep breaths», but have their own circuit.

Vlemincx et al. (2016) showed that a voluntary deep breath like the conscious sigh, reduces physiological tension measured by EMG while also increasing subjective relief. The effect is therefore real and measurable, which is why random deep breaths are also used (if the user wants, since they can easily be switched off) during deep work intervals in Focus or Ultrafocus mode.

The most relevant study on the physiological sigh comes from Balban et al. (2023), from Stanford University. Published in Cell Reports Medicine and with the participation of Andrew Huberman himself, it studied 108 participants over 28 days, pitting four breathing techniques against each other: cyclic sighing (physiological sigh), Box Breathing, cyclic hyperventilation (Wim Hof style) and Mindfulness meditation.

The cyclic sigh produced the greatest daily improvement in mood of all conditions, significantly surpassing Mindfulness meditation.

This occurred even with just a few breaths and the benefits increased with consecutive days of practice, so it’s worth making space for this practice over time.

That said, it must be noted that cyclic hyperventilation, when you read the study, was implemented «halfway» in a somewhat sloppy way. Had it been applied correctly and completely it would likely have shown better effects, but that’s another matter.

The extended exhalations

Another technique used in Mind Focus for relaxation and control of our nervous system is the practice of extended exhalation, whereby we breathe out for longer than we breathe in.

The app uses a 4:6 ratio, inhaling for 4 seconds through the nose and exhaling for 6 through the mouth (typically closing the lips to attenuate the airflow again, as if blowing through a straw). According to the data, other ratios can work, but they must follow the principle of an exhalation longer than the inhalation.

Whenever we do that, we activate the parasympathetic nervous system (the one governing calm and rest) in a way that goes beyond simple relaxation.

Zaccaro et al. (2018) systematically reviewed 15 studies on slow breathing and found consistent evidence: it increases heart rate variability (HRV), increases alpha power on the EEG and reduces anxiety, depression and irritability.

And this doesn’t occur as a pleasant side effect, but as a direct physiological consequence of increased parasympathetic activity.

Breathing is an incredibly powerful key for controlling the nervous system. In fact, that’s why I’ve been practising breathwork for many years (it has literally changed my life). And that’s also why I’m working on an upcoming app dedicated to said breathwork with the same goals and premises as Mind Focus: simple, private, focused, offline, going beyond what currently exists and, once again, no subscriptions.

But returning to the science, Laborde et al. (2022), in a meta-analysis, confirmed that slow voluntary breathing significantly increases RMSSD (a marker of vagal activity, referring to the vagus nerve, one of the main controllers of our mood) and that an exhalation longer than an inhalation specifically potentiates that effect. This was specifically with 6 cycles per minute breathing like Mind Focus uses, with emphasis on the outward breath, the one that maximises cardiac coherence.

Attentional training exercises

The attention that has been stolen from us, in order to turn us into stimulus-slave robots chasing the latest trend, is a muscle.

And that phrase may sound a bit cliché, but the biology behind it is not.

The visual concentration exercises in Mind Focus (such as the practice of holding one’s gaze on a fixed object without the mind wandering) have their equivalent in the yogic practice called trataka, which has science behind it and not only mysticism.

Raghavendra and Singh (2016) found significant improvements in the Stroop test (a measure of selective attention and response inhibition) after a session of visual concentration.

Similarly, Swathi et al. (2021) observed improvements in visuospatial working memory after two weeks of training (p < 0.001 on the Corsi task).

Mallick and Kulkarni (2010) in turn measured significant increases in critical flicker fusion frequency, a neurological marker of cortical activation.

In other words, we’re talking about measurable changes in the activation of attention pathways in our brain.

And yes, it means work, but it’s very much worth it.

Conscious reading

Reading, that lost art… which can give us our attention back, in addition to providing countless cognitive and psychological benefits that go far beyond that.

But let’s focus again on what concerns us now, since concentration is the subject here.

That focused reading (on paper or e-ink, without distractions and as deliberate practice) is one of the most potent attentional interventions available.

Seriously. The reason almost no one mentions it is because it can’t be monetised very well, and that’s how life works.

Also, like most things that are actually effective, conscious reading is not glamorous, complicated, nor does it shimmer with the thousand ephemeral and empty flashes of novelty.

But it is tremendously powerful.

Delgado et al. (2018) analysed over 170,000 participants in a meta-analysis of 54 studies and their first conclusion was clear: reading comprehension on screen is significantly lower than on paper (g = −0.21), and that effect grew over the 18 years of the study, suggesting that digital habits are actively training a more superficial processing mode.

So if we want to reclaim our attention, the first order of business is to make time and space to step away from screens and open the pages of a book.

Maryanne Wolf (at UCLA, in California) has spent decades researching the neural circuits that deep reading activates: empathy, critical analysis, reflective thinking… These are circuits that are trained or atrophied depending on the type of reading you practise. And the fast, fragmented reading of screens does not activate them in the same way.

But with conscious reading we force ourselves to concentrate on one single thing, to find ourselves immersed in it until we reach the coveted state of flow, about which I also go into greater depth here.

Reading (preferably fiction on paper, which is by far what reaps the most cognitive benefits), used as a training practice, is applied neuroscience.

And it’s also a lost pleasure, but that’s another matter.

Circadian rhythms in isochronic tones

Two of the fundamental optimisations in the isochronic tones that Mind Focus uses are, as I detail further here, their intelligent mathematical generation (rather than using prerecorded loops as every other alternative does) and their adaptation to circadian rhythms, the natural activation and rest rhythms that people follow throughout the day.

This is something also not taken into account in other isochronic tones, and it’s worth knowing why it’s useful.

Schmidt et al. (2007) reviewed how circadian variations affect cognitive functioning and found that performance fluctuations according to time of day affect a wide range of tasks: attention, executive functions, memory…

The brain doesn’t perform the same at ten in the morning as it does at eleven at night, and Mind Focus takes this into account, modifying tones in an adaptive and intelligent way, according to those cycles.

May et al. (2023) documented the «synchrony effect», which implies that optimal cognitive outcomes occur when the work schedule aligns with the individual’s circadian peak. This has an impact on real-world outcomes (test grades, decision-making, cognitive performance…) and not only in laboratory conditions.

That’s the reason the tones in Mind Focus change frequency according to the time of day, to adapt naturally to our brain by working with it, rather than against it.