If you’ve read my last post I hinted that today we would discuss filtering. Instead I think I want to take this a different direction. That isn’t to say we won’t go over filtering, we most definitely will. Today I want to cover something else though, significance. So you’ve recorded your signal, took an ensemble average, and now how do we tell if it actually means something, or if you are looking at an artificial or arbitrary separation in your data (IE two separate conditions lead to no difference in your data). Let’s look at significance.*
Noise, it can be troublesome. Whether you are studying and someone is being loud or you are trying to record something, noise is everywhere <stern look at people who talk during movies>. Interestingly enough the concept of noise in a signal recording sense isn’t all too different from dealing with talkative movie goers, so let’s talk noise!*
So you wanna use a spectrogram… but why? What does a spectrogram do that we can’t do using some other methods for signal processing? As it turns out, there is a lot of reasons you may want to use the spectrogram and today we are going to cover some of those reasons and number four may shock you! (okay not really, what do you think this is a clickbait website?)*
Well ten days in and we’ve just introduced the idea of the spectrogram. While a lot of this information is just the broad strokes, I like to think that we’ve covered enough to give you a good idea about how to use these tools and what they are used for. However, we do need to discuss a limitation to the spectrogram, something called the banana of uncertainty, okay not quite the name, but you’ll see why I keep calling it that.*
Last post we introduced a new tool in our arsenal of signal processing analysis, the spectrogram. Without knowing how to read it, it just looks sort of like a colored mess. Don’t get me wrong, it is an interesting looking colored mess, but a mess nonetheless. Well today we are going to talk about how to interpret the plot and why exactly we would ever use this seeming monstrosity.*
To (somewhat) continue with our signal processing theme that we have going on at the moment, over the next few days, let’s look at something called the spectrogram. It’s three dimensions of fun!*
Waves! We’re officially one week through 365 Days of Academia! Woo! 1 week down, 51(.142…) weeks left! Let’s wrap up this weeks theme (there wasn’t originally a theme, but it kind of ended up that way) by talking about other ways we can get to the frequency domain. Specifically, let’s stop the wave puns and let’s talk wavelets!*
Okay, if you’ve been keeping up with these posts, we know about Welch’s method, Thomson’s method, the things that make them different, and the things that make them similar. The thing that both of these transforms rely on is the Fourier transform. What is the Fourier transform? Well, something I probably should have covered first, but whatever this is my blog we do it in whatever order we feel like, so let’s dive in!*
In this digital age, with phones at our fingertips, you would think that access to constant communication would make us feel closer to one another. But a new study shows that may not be the case. In fact, cell phone use might actually lead to feeling less socially connected, depending on your gender or cell phone habits.
Conducted at the BioMag laboratory at the Helsinki University Hospital, a new patient study could open a new opportunity to rehabilitate patients with spinal cord damage. In a new study which two patients with spinal cord injuries received a form of treatment that combined transcranial magnetic stimulation with simultaneous peripheral nerve stimulation given repeatedly for nearly six months.
Tablet and laptop users beware. Using digital platforms such as tablets and laptops for reading may make you more inclined to focus on concrete details rather than interpreting information more abstractly, according to a new study. The findings serve as another wake-up call to how digital media may be affecting our likelihood of using abstract thought.
Happiness. It’s something we all strive for, but how do we measure it — as a country? A global community? Not so surprisingly, researchers are turning to social media to answer these questions and more. In a newly published study, computer scientists used two years of Twitter data to measure users’ life satisfaction, a component of happiness.
As a society we have become incredibly reliant on technology, from spell check to GPS, we are slowly being replaced by computers. Need more proof, a computer can routinely beat us at chess, an AI wrote portions of a book that went on to almost win a writing contest, and if you want scary robotics enter Boston dynamics spot. So the question is, have we outlived our place in the world? Not quite. Welcome to the front line of research in cognitive skills, quantum computers and gaming.
Rustling leaves, a creaking branch: To a mouse, these sensory impressions may, at first, seem harmless — but not if a cat suddenly bursts out of the bush. If so, they were clues of impending life-threatening danger. Researcher Robert Gütig has now found how the brain can link sensory perceptions to events occurring after a delay.
Why send a message back in time, but lock it so that no one can ever read the contents? Because it may be the key to solving currently intractable problems. It turns out that an unopened message can be exceedingly useful. This is true if the experimenter entangles the message with some other system in the laboratory before sending it.
Researchers have imaged in unprecedented detail the three-dimensional structure of supercoiled DNA, revealing that its shape is much more dynamic than the well-known double helix.
Researchers at USC and Wake Forest Baptist Medical Center have developed a brain prosthesis that is designed to help individuals suffering from memory loss. The prosthesis, which includes a small array of electrodes implanted into the brain, has performed well in laboratory testing in animals and is currently being evaluated in human patients.
It’s not lightsaber time… at least not yet. But a team including theoretical physicists from the National Institute of Standards and Technology (NIST) has taken another step toward building objects out of photons, and the findings* hint that weightless particles of light can be joined into a sort of “molecule” with its own peculiar force.
An experiment to determine the effects of positive and negative user comments to items posted by media organizations on Facebook news channels showed, surprisingly, that the influence of user comments varied depending on the type and number of user comments. Negative comments influenced the persuasiveness of a news article, while positive comments did not, and a high number of likes did not have the expected bandwagon effect.
Quantum theory is one of the great achievements of 20th century science, yet physicists have struggled to find a clear boundary between our everyday world and what Albert Einstein called the “spooky” features of the quantum world, including cats that could be both alive and dead, and photons that can communicate with each other across space instantaneously.
A study authored by two University of Wisconsin-Madison graduate students indicates that while playing video games can improve mood, violent games may increase aggressive outcomes. The researchers looked at how video games may be used to manage emotions — specifically, whether playing the games can improve mood.
Moving closer to the possibility of “materials that compute” and wearing your computer on your sleeve, researchers at the University of Pittsburgh Swanson School of Engineering have designed a responsive hybrid material that is fueled by an oscillatory chemical reaction and can perform computations based on changes in the environment or movement, and potentially even respond to human vital signs. The material system is sufficiently small and flexible that it could ultimately be integrated into a fabric or introduced as an inset into a shoe.
New, ultra-high-field magnetic resonance images (MRI) of the brain by researchers at the University of Illinois at Chicago provide the most detailed images to date to show that while the brain shrinks with age, brain cell density remains constant. The images provide the first evidence that in normal aging, cell density is preserved throughout the brain, not just in specific regions, as previous studies on human brain tissue have shown.
A new study shows that while video game players (VGPs) exhibit more efficient visual attention abilities, they are also much more likely to use navigation strategies that rely on the brain’s reward system (the caudate nucleus) and not the brain’s spatial memory system (the hippocampus). Past research has shown that people who use caudate nucleus-dependent navigation strategies have decreased grey matter and lower functional brain activity in the hippocampus.
Venus, the place where women are from… supposedly. To say Venus has a harsh climate would be an understatement, this is one of many reasons why we will never (or maybe not soon) see a “long lasting” Venus rover counterpart to our Mars rover missions. Still, the planet (much like all the other plants) can teach us a lot about not just our own origins, but the origins of the universe. Also like all our neighbor planets Venus is hiding something beneath its brilliant shroud of clouds, a mystery that might be soon solved, all thanks to a new re-analysis of twenty-year-old spacecraft data.
It’s a project that would make Tesla proud. Just imagine being able to instantaneously run an optical cable or fiber to any point on earth, or even into space. That’s what researchers are trying to do. Did I mention it was instantaneous and involved no connection other than the air around us? Well if you are as excited as I am, then you should read on! If not, two words, laser weapons!!
Fire, brimstone, four horsemen, doomsday seems pretty bleak in the biblical context. From a scientific perspective, global warming and the need for fresh water will probably plunge people into chaos, which seems like a more likely doomsday model. Unfortunately there are other ways in which the world could come crashing down around us, today I wanted to shed light on just one of those ways.
The most plausible [in my opinion] doomsday scenario comes not from an external force but from our imagination. Let me explain, most money that we deal with is just a placeholder, a social construct, a number on a screen and when dealing with the stock market, it gets even fuzzier, you can essentially make bets for money on [you guessed it] money.
Are you real? What is ‘real’, more of a philosophy question than a scientific one, but what if a computer worked like your brain? What if, one day the line between computer and human were blurred? That day might be coming sooner than you think.
Currently there are two major problems with designing a robotic brain. The first is hardware, the brain is an incredibly complex thing that we don’t even fully understand, even if we could theoretically produce something close to that work of art there is that second problem– The software, designing software to take advantage of that type of power would take something short of genius to do, especially if it were going to be something easy enough that you or I could use.