With regard to listening without headphones specifically, you might find it irritating if you are someone who suffers from motion sickness, depending on how the track is created. If you were listening to binaural beats, they really need headphones to work properly. If you are in a room and closer to one speaker you may not even hear binaural beats properly, and if sitting off centre in the room generally, that may have unsettled you if you have motion sickness as the tones try to form a beat in your head. If it was just a standard isochronic tones theta track that shouldn’t be irritating if you have motion sickness.
Words could be great stress relievers. One technique to quell sudden stress is to repeat a phrase from which you draw power and strength. “Think positively about releasing what is bothering you by repeating a positive mantra that uplifts you such as, ‘I am at peace,’ ‘All is well,’ ‘I choose to think thoughts that serve me,’ or ‘I love and believe in myself fully,’” says Carol Whitaker, life transformation expert and the author of Ridiculously Happy! The Secret to Manifesting the Life and Body of Your Dreams. “This too shall pass” is another good one. Repeating a mantra is actually a type of meditation that can make you more resilient to stress—some studies show it can actually alter your brain’s neural pathways. You can place reminders of your mantras near the places you tend to get stressed, like your work space. “I actually keep a file on my computer of great quotes and inspiring sayings. So when I’m feeling overwhelmed by life’s struggles, I clip them to my screensaver, post them on my social media, and even print them out to put on my refrigerator or desk,” Dr. Serani says.

All of this is entirely understandable, even somewhat predictable. Unfortunately, it quickly becomes counter-productive. Such experiences, while having a certain feeling of solidity to them, are largely the product of our desires and expectations. Did your face get flushed? One look in the mirror confirms it did. Was this caused by the entrainment? No, it was not. It was the result of what was sought after and what was expected or even hoped for.

Brainwaves, or neural oscillations, share the fundamental constituents with acoustic and optical waves, including frequency, amplitude and periodicity. Consequently, Huygens' discovery precipitated inquiry[citation needed] into whether or not the synchronous electrical activity of cortical neural ensembles might not only alter in response to external acoustic or optical stimuli but also entrain or synchronize their frequency to that of a specific stimulus.[16][17][18][19]
The activity of neurons generate electric currents; and the synchronous action of neural ensembles in the cerebral cortex, comprising large numbers of neurons, produce macroscopic oscillations. These phenomena can be monitored and graphically documented by an electroencephalogram (EEG). The electroencephalographic representations of those oscillations are typically denoted by the term 'brainwaves' in common parlance.[4][5]