It’s Not a ‘Stream’ of Consciousness

from nytimes

MAY 8, 2015

IN 1890, the American psychologist William James famously likened our conscious experience to the flow of a stream. “A ‘river’ or a ‘stream’ are the metaphors by which it is most naturally described,” he wrote. “In talking of it hereafter, let’s call it the stream of thought, consciousness, or subjective life.”

While there is no disputing the aptness of this metaphor in capturing our subjective experience of the world, recent research has shown that the “stream” of consciousness is, in fact, an illusion. We actually perceive the world in rhythmic pulses rather than as a continuous flow.

Some of the first hints of this new understanding came as early as the 1920s, when physiologists discovered brain waves: rhythmic electrical currents measurable on the surface of the scalp by means of electroencephalography. Subsequent research cataloged a spectrum of such rhythms (alpha waves, delta waves and so on) that correlated with various mental states, such as calm alertness and deep sleep.

Researchers also found that the properties of these rhythms varied with perceptual or cognitive events. The phase and amplitude of your brain waves, for example, might change if you saw or heard something, or if you increased your concentration on something, or if you shifted your attention.

But those early discoveries themselves did not change scientific thinking about the stream-like nature of conscious perception. Instead, brain waves were largely viewed as a tool for indexing mental experience, much like the waves that a ship generates in the water can be used to index the ship’s size and motion (e.g., the bigger the waves, the bigger the ship).

Recently, however, scientists have flipped this thinking on its head. We are exploring the possibility that brain rhythms are not merely a reflection of mental activity but a cause of it, helping shape perception, movement, memory and even consciousness itself.

What this means is that the brain samples the world in rhythmic pulses, perhaps even discrete time chunks, much like the individual frames of a movie. From the brain’s perspective, experience is not continuous but quantized.

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Another clue that led to this discovery was the so-called wagon-wheel illusion, in which the spokes on a wheel are sometimes perceived to reverse the direction of their rotation. This illusion is easy to induce with a strobe light if the rotation of the wheel is such that each strobe flash captures the spoke location slightly behind the location captured on the previous flash, leading to the perception of reverse motion. The illusion results from “sampling” the scene in discrete frames or time chunks.

The telling fact, for perceptual scientists, is that this illusion can also occur during normal observation of a rotating wheel, in full daylight. This suggests that the brain itself, even in the absence of a strobe light, is sampling the world in discrete chunks.

Scientists have uncovered still more clues. It turns out, for example, that our ability to detect a subtle event, like a slight change in a visual scene, oscillates over time, cycling between better and worse perceptual sensitivity several times a second. Research shows that these rhythms correlate with electrical rhythms of the brain.

If that’s hard to picture, here’s an analogy: Imagine trying to see an animal through a thick, swirling fog that varies in density as it drifts. The distinctness of the animal’s form will oscillate with the density of the fog, alternating between periods of relative clarity and opaqueness. According to recent experiments, this is how our perceptual systems sample the world — but rather than fog, it’s brain waves that drive the oscillations.

This is not to say that the brain dances to its own beat, dragging perception along for the ride. In fact, it seems to work the other way around: Rhythms in the environment, such as those in music or speech, can draw neural oscillations into their tempo, effectively synchronizing the brain’s rhythms with those of the world around us.

Consider a study that I conducted with my colleagues, forthcoming in the journal Psychological Science. We presented listeners with a three-beat-per-second rhythm (a pulsing “whoosh” sound) for only a few seconds and then asked the listeners to try to detect a faint tone immediately afterward. The tone was presented at a range of delays between zero and 1.4 seconds after the rhythm ended. Not only did we find that the ability to detect the tone varied over time by up to 25 percent — that’s a lot — but it did so precisely in sync with the previously heard three-beat-per-second rhythm.

Why would the brain do this? One theory is that it’s the brain’s way of focusing attention. Picture a noisy cafe filled with voices, clanging dishes and background music. As you attend to one particular acoustic stream — say, your lunch mate’s voice — your brain synchronizes its rhythm to the rhythm of the voice and enhances the perceptibility of that stream, while suppressing other streams, which have their own, different rhythms. (More broadly, this kind of synchronization has been proposed as a mechanism for communication between neural networks within the brain.)

All of this points to the need for a new metaphor. We should talk of the “rhythm” of thought, of perception, of consciousness. Conceptualizing our mental experience this way is not only more accurate, but it also situates our mind within the broader context of the daily, monthly and yearly rhythms that dominate our lives.

Gregory Hickok, a professor of cognitive science at the University of California, Irvine, is the author of “The Myth of Mirror Neurons: The Real Neuroscience of Communication and Cognition.”

A version of this op-ed appears in print on May 10, 2015, on page SR9 of the National edition with the headline: Rhythms Of the Brain. Order Reprints| Today's Paper|Subscribe

Is cosmic consciousness the next stage of human evolution?

from inquirer.net

Apr 28, 2015

One suddenly realizes the unity or oneness of the whole universe

BY JAIME T. LICAUCO

Last week I wrote about the possibility of obtaining knowledge not from our normal five physical senses, but from something beyond them. Such knowledge has been called by various names, such as intuition, extrasensory perception, etc.

But there is another type of knowledge higher than this, which is more difficult to describe in words. And much fewer people have experienced it, unlike intuitive knowledge of something mundane or physical.

This type of knowledge or awareness has also been called by various names by different cultures, such as cosmic consciousness in the West, samadhi in Indian yoga philosophy and satori in Japanese Zen Buddhism.

However, there is a fundamental difference among these mystical states. Cosmic consciousness, for example, cannot be obtained deliberately or consciously. It usually comes spontaneously, without deliberate effort nor intention. Samadhi is a state of enlightenment attained through years of mental discipline, meditation and even fasting. Samadhi is the ultimate goal of yoga, satori the ultimate goal of Zen practice.

Samadhi is achieved when the human mind unites with the universal mind. Satori, on the other hand, is achieved when one bypasses the logical mind and achieves oneness with universal truth.

No distinction

In cosmic consciousness, one suddenly realizes the unity or oneness of the whole of the universe, that there is no distinction between object and subject, that everything is really one. One also gets the feeling that all of this knowledge of the world appears useless and of no consequence or value at all. And that there is a higher awareness that is more valuable than anything else.

Such a state of cosmic consciousness may last for only a few seconds or minutes, or for several days. One who experiences it is forever transformed. He or she is no longer the same person. And all knowledge of the world seems to be inconsequential, in comparison with this new and higher level of awareness.

This, I believe, happened to me quite unexpectedly in 1975, when I knew nothing about such things as cosmic consciousness, ESP or mystical phenomena.

I couldn’t remember any more the details, as it happened a long time ago, but I knew I was in a meditative state. And I was alone at home, thinking of nothing in particular.

Then, without warning, my mind was transported to another level of understanding or another universe, like nothing I have ever experienced before. Everything became connected to everything else, that there was no longer any distinction between me and everything else in the universe, that everything had become one or part of that universal one.

It was mind-blowing. Even nonliving things, like stones, minerals, water, were all alive and communicating with one another. Subject and object became indistinguishable.

Mystical experience

I didn't know what hit me that day. I kept such experience from everybody else, reluctant to talk about it because I couldn't explain it.

Then, many years later, I read Dr. William James’ “Varieties of Religious Experience,” which explained it as a religious mystical experience.

But my experience was nothing religious at all. It was not connected to any religion. It was beyond all religion.

Again, many years later, I came across the book of Richard Bucke on cosmic consciousness. The many examples of people who have experienced cosmic consciousness somehow resonated with me and I knew then that was what I had, although I could not compare myself with those famous people.

P.D. Ouspensky, a famous Russian mathematician and mystic who was a long-time disciple of Gurdjieff, described his experience with cosmic consciousness in his book, “A New Model of the Universe.”

“I am reading the chapter on levers. And all at once a multitude of simple things, which I knew as independent and having nothing in common became connected and united into a great whole. A stick pushed under a stone, a pen knife, a shovel, a seesaw, and all the things one and the same, they are all ‘levers.’

“In this idea there is something both terrifying and alluring. How is it that I did not know it? Why has nobody spoken about it? Why I am made to learn a thousand useless things and not told about this? All that I am discovering is so wonderful and miraculous that I became more and more enraptured, and I am gripped by a certain presentment of further revelations waiting me. It is as though I already feel the unity of all and am overcome with awe at the sensation.”

Bucke, author of “Cosmic Consciousness,” described his experience with this elusive and fleeting type of knowledge and listed down its characteristics as follows: “Its sudden appearance, a subjective experience of inner light, moral elevation, intellectual illumination, a sense of immortality, loss of fear of death, and loss of a sense of sin.”

In his book, Bucke listed down some 35 individuals who had experienced cosmic consciousness, such as Jesus Christ, Plotinus, Mohammed, Buddha, William Blake, Francis Bacon, Walt Whitman, Socrates, Swedenborg, Ralph Waldo Emerson, etc.

Bucke’s experience of cosmic consciousness seems to have some moral or religious dimensions. I believe, however, that because all becomes one, cosmic consciousness is beyond religion and morality. From my limited experience of it, all of reality appears to be one and the same thing.

He considers cosmic consciousness the next stage of human evolution and development.

Do animals have consciousness?

from scienceline.org

The way scientists answer this animal consciousness question has a big effect not only on their research, but also your medicine cabinet

Does this little guy have consciousness? Researchers are divided as to whether it’s even a question we should be answering. [Image credit: Flickr user S. J. Pyrotechnic]

By Chelsey B. Coombs | Posted March 6, 2015

There’s a rat in a cage with two sides: one bright and one dark. One of the rat’s survival mechanisms is to favor the dark side and avoid the bright side at all costs. But when the rat goes into the dark side of the cage, it gets shocked. After a few shocks coincide with its favorite habitat situation, it remains on the bright side despite its lifelong instincts. Is the rat now afraid of the dark, or is he simply trained to avoid it? 

If the rat were a human, he’d probably tell us he’s afraid of the shocks in the darkness, which shows the ability to feel emotions. We know humans have the capacity for consciousness because we think, make decisions, have feelings and a sense of self. And each of us believes that other humans have the same ability. But we don’t yet have the technology to go into the minds of those around us to see and feel what they do.

This distinction is all the more difficult when it comes to non-human animals. We think that our pets are happy when we come home, or sad when we punish them for ruining the brand new couch. But we can’t go into their minds to really know how they’re feeling, or whether they are actually conscious.

The animal consciousness debate has higher stakes than a simple desire to know whether Fido or Fluffy has feelings. It affects how scientists think about and conduct their research on non-human animals, and whether researchers should or should not make assumptions about their subjects’ consciousness while doing their experiments. One side believes scientists must separate the mechanisms that detect and respond to threats from those that create conscious feelings of fear, while the other believes these mechanisms are one and the same.

But this is not a new debate.

“It has been going on forever,” said New York University neuroscientist Joe LeDoux, one of the most vocal of a group of researchers who think non-human animal consciousness isn’t relevant in experiments or even scientifically resolvable. “The basic idea is about how many assumptions scientists are willing to make about consciousness.”

In a 2014 paper in the Proceedings of the National Academy of Sciences titled “Coming to terms with fear,” LeDoux elaborated on his argument, writing, “we can learn quite a bit that is relevant to human feelings from studies of animals without making any assumptions about [their] consciousness.”

But another group of neuroscientists — one of the most vocal being Jaak Panksepp, a neuroscientist at Washington State University — want to factor consciousness into their experiments. In July 2012, at the conclusion of the Francis Crick Memorial Conference on Consciousness in Human and Non-human Animals, Panksepp, along with a White House advisor and other neuroscientists, published The Cambridge Declaration on Consciousness. This declaration, whose signing was witnessed by physicist and cosmologist Stephen Hawking, emphasized that scientific evidence showed clearly that non-human animals have “conscious states along with the capacity to exhibit intentional behaviors.” They argued that all mammals and birds, as well as many other organisms, have the same brain structures and substrates that make consciousness possible in humans, which makes consciousness possible for them as well.

Animal behaviorists have been discussing animal consciousness as long as their field has existed, since Charles Darwin wrote his 1872 book, “The Expression of the Emotions in Man and Animals.” But the issue has deep philosophical roots. Even French philosopher and mathematician René Descartes got in on the debate, writing in his 1637 treatise “Discourse on Method,” “it is more probable that worms and flies and caterpillars move mechanically than that they all have immortal souls.”

John Watson, the early 20th century psychologist known as the father of behaviorism, which focuses on studying outward behavior rather than inward consciousness, had a very similar view. Watson and other behaviorists thought that the only way to understand animals was to observe the causes and effects of their behaviors, rather than to ruminate on whether the animals made conscious behavioral choices. They insisted, for example, that a chastised dog cowering in a corner isn’t feeling fear: He’s actually exhibiting a reflexive behavior triggered by a stimulus — a position bolstered by Russian physiologist Ivan Pavlov’s experiments with salivating dogs.

“The behaviorists took a very strong stance right from the beginning with the ideas that emotions were something you couldn’t measure in a nonhuman animal, so there was no point in going down that route,” said Penn State University biologist Victoria Braithwaite, who studies pain perception, fear and suffering in fish. “It was very clean cut, it was clinical. They thought we shouldn’t be studying things we don’t understand.”

Some researchers, like the founder of psychoanalysis Sigmund Freud tried to delve into how human behavior was influenced or driven by inner feelings and desires. But animal behaviorists almost unanimously focused solely on the observable behaviors themselves, rather than trying to experimentally manipulate or even delve into animal consciousness.

The classical behaviorist point of view has reigned since the 1950s, but there was a silent minority toiling away to try to prove that non-human animals have consciousness.

“[Consciousness] is a century old dilemma that the academic behaviorists decided to close the book on many years ago,” Panksepp said in a recent interview. “I turned out to be among the scientists to open the book.”

Panksepp was inspired by the work of American psychologists Peter Milner and James Olds, who in 1954 discovered the brain reward system. By using electrodes to target certain brain regions in rats, Milner and Olds found they could train the creatures to perform behaviors like pressing levers so they could get more of this deeply rewarding brain stimulation. The brain’s reward system is activated to reinforce certain behaviors that cause pleasure and researchers believe this system is responsible for drug addiction.

Panksepp began using similar deep brain stimulation techniques in his own research. But rather than lying back to enjoy this reward system stimulation, the rats would actually change their behaviors.

“Every animal I stimulated in the rewards system explored [its environment],” he said. “I immediately started seeing this as an emotional system as opposed to just a reward system. It was through this emotional system that animals explore the world,” Panksepp added, and can thus better anticipate threats to their survival.

Panksepp called this branch of the reward system the seeking system. Since then, he and other pro-consciousness scientists have concluded that animals have systems not only for seeking, but also rage, lust, maternal care, panic, play and fear. Researchers were able to map the brain’s so-called play system using rat laughter, a sound that’s too high for humans to hear but sounds like bird calls when manipulated into the human hearing range.

“Every animal I tickled was chirping like crazy and they became very fond of my hand like a little puppy chasing you around,” Panksepp said.

One of his doctoral students began to map the brain areas that caused the rats to laugh, and found that this laughter was, according to Panksepp, a “marker for good feelings” or social joy.

But LeDoux argues differently. He thinks that the neural circuitry associated with fear conditioning, which he argues is a response to a threat, is separate entirely from any circuitry that could create conscious fear.

LeDoux says that in a variety of experiments in humans, subliminal threats were able to cause physiological responses, such as increased skin conductance caused by sweat, without subjects being aware of the threat, even when they are asked to describe how they are feeling at that moment.

“We can trigger these kinds of states that if you measured in an animal, you would say the animal is feeling fear,” LeDoux said. “But if we can’t use that information to conclusively demonstrate that a human is feeling fear or experiencing that state, then we certainly can’t use it every time an animal looks like he may be feeling afraid.”

This uncertainty explains why LeDoux and his camp call this reaction a threat response rather than fear.

Like LeDoux, Braithwaite acknowledges we still don’t have all the information on human consciousness, but in the animal consciousness debate she sides with Panksepp.

“It’s the 21st Century. We can put people on the moon but we still don’t understand our own consciousness,” she said. “I think we need to recognize that we’re part of an evolutionary progression and it would be very bizarre for animals to not have forms of consciousness.”

This isn’t simply a war of competing factions who just want to be right. According to both Panksepp and LeDoux, whatever direction the field goes in will affect how scientists look for new human psychiatric medications and how animals in research laboratories are used in experiments.

Panksepp, for instance, developed a new antidepressant that is currently undergoing FDA testing. “It is a molecule that facilitates social joy, mainly rat laughter. Lo and behold, we developed molecules that were safe and non-addictive to modulate this complex neurochemical pathway, and it’s been in human testing now for four years.”

While Panksepp believes researchers should take animal emotions into account when looking for these new medications, LeDoux believes scientists must separate the mechanisms that detect and respond to threats and the mechanisms that create conscious feelings of fear.

LeDoux says behavioral therapy addresses non-conscious brain circuitry more directly, while cognitive, or talk, therapy addresses the conscious circuitry. But many therapists use both methods. He argues that from a neuroscientific standpoint this is not as effective at helping patients, because the different predisposing factors that cause psychiatric problems are susceptible to different treatments.

“If we’re confusing the experience and the automatic detection and response systems, we’re not really doing justice to how we’re curing anxiety disorders,” LeDoux said. “We’re not being clear about what’s controlling different aspects of it and how those different things should be treated in people.”

There’s a lot more at stake for the rat in the dark and light cage than most would expect, and the way researchers handle their thinking of the rat’s conscious and unconscious experiences has great implications for human applications. For now, this shocking controversy continues on.

Scientists playing sleight of hand games

from leaderpost.com


BY BETHANY LINDSAY, POSTMEDIA NEWS FEBRUARY 12, 2015

Can questions about something as fundamental as the existence of free will be answered with a simple magic trick?

It may sound strange, but a new study from researchers in Vancouver and Montreal uses magicians' mind tricks as a gateway to exploring human consciousness and decision-making. In a street magic experiment, lead author Jay Olson asked 118 strangers to pick a random card as he riffled through the pack, intentionally showing one card for longer than the rest.

The results were remarkable.

Ninety-eight per cent of people picked the target card, and an impressive 91 per cent believed that they had made that choice freely, without any influence from the magician.

"It was pretty cool," said co-author Ronald Rensink, a psychology and computer science professor at the University of British Columbia. "This would seem to be supporting the view that your conscious mind doesn't really decide.

"It's the non-conscious mind that makes the decision-making. ... Your conscious mind, some people would argue, only vetoes the selection."

Magicians have been exploiting the unconscious mind for centuries to create a sense of wonder in their audiences, and that makes magic a perfect vehicle for studying psychology, according to co-author Alym Amlani, a magician and accounting professor at Kwantlen Polytechnic University.

"We're now able to tap into the effects that have been, for lack of a better word, fooling people for years.

"We're in a position now that we can better understand why they work," Amlani said. "For everyday people, it's just incredible that we can actually have our decisions influenced outside of our awareness."

The researchers also attempted to replicate the results from the street magic experiment in the lab using a computer program that showed participants a series of 26 images of cards. The target card was shown for about three times as long as the rest.

Participants in this part of the study chose the target card in 30 per cent of the trials. That result isn't as jaw-dropping as what the researchers saw on the street, but it is still significant, Rensink said.

"I was just happy to get our foot in the door. It could be with better timing parameters we could get a stronger effect," he said.

"Or it could be there's something about the social interaction with the magician."

Recent years have seen an increase in research focused on both "magic" and decision-making, according to Rensink, and the results of studies like this could have wide implications.

"If you're an advertiser, for example, you really want to appeal to the non-conscious mind, that part of the viewer, instead of making a formal argument," he said. "It's both kind of cool and kind of scary."

© Copyright (c) The Regina Leader-Post

 

 

Human Soul Found? Quantum Theory Of Consciousness ‘Orch OR’ Claims Both Science And Religion Are True

from  inquisitr.com

Has the human soul been found by science? A controversial quantum theory of consciousness called “Orch OR” (which stands for “orchestrated objective reduction”) recently had a review, and the scientists supporting this idea are claiming the recent discovery of quantum vibrations in “microtubules” inside brain neurons corroborates their beliefs.

In a related report by the Inquisitr, Stephen Hawking fears the Terminator movies may actually come true, but to this day, the “lowly” human brain still beats out supercomputerson multiple fronts. Louis Del Monte, the author of The Artificial Intelligence Revolution, also believes an AI singularity event will occur by 2045, but so far, computer AI can’t even pass the Turing test.

In most religions, the totality of being human is divided into three parts; mind, soul, and body. Christianity, Judaism, Islam, and other religions typically equate the mind to the physical human brain, which works in conjunction with an immaterial human soul. What has had philosophers and scientists arguing for thousands of years is exactly how this process functions from a mechanical viewpoint. When it comes to the philosophy of the mind, dualism and physicalism have competed for the beliefs of scientists, with the latter claiming that all which exists in our world, including consciousness, is physical.

On the side of physicalism, some scientists claim the soul or consciousness can be reduced to mere computations conducted within the neural networks in the human brain, which means all consciousness can be explained by algorithms. Other scientists believe believe that quantum processes attributed to the human soul work in partnership with the observable neurological processes to produce the experience of human consciousness, although one is not completely dependent on the other to function. Essentially, these scientists claim the human brain is a quantum computer, and the informational state of qubits are influenced by the human soul.

One such scientist is Stuart Hameroff, Professor Emeritus at the Department of Anesthesiology and Psychology and the Director of the Center for Consciousness Studies at the University of Arizona. He and Sir Roger Penrose, mathematical physicist at the Mathematical Institute and Wadham College and University of Oxford, believe overall brain function derives from quantum level microtubule vibrations.

“The origin of consciousness reflects our place in the universe, the nature of our existence. Did consciousness evolve from complex computations among brain neurons, as most scientists assert? Or has consciousness, in some sense, been here all along, as spiritual approaches maintain?” ask Hameroff and Penrose in the current review, according to Science Daily. “This opens a potential Pandora’s Box, but our theory accommodates both these views, suggesting consciousness derives from quantum vibrations in microtubules, protein polymers inside brain neurons, which both govern neuronal and synaptic function, and connect brain processes to self-organizing processes in the fine scale, ‘proto-conscious’ quantum structure of reality.”

In other words, they believe they’ve found scientific evidence for the human soul. They claim six testable prediction published in 1998 have been fulfilled, and none have been falsified. As an example, they cite the “recent discovery of warm temperature quantum vibrations in microtubules inside brain neurons,” which is a big deal since man-made quantum computers typically require icy conditions in order to function at all. In addition, they point to research which “suggests that anesthesia, which selectively erases consciousness while sparing non-conscious brain activities, acts via microtubules in brain neurons.” From a practical medical perspective, they also believe “treating brain microtubule vibrations could benefit a host of mental, neurological, and cognitive conditions.”

From a religious perspective, Hameroff believes their Orch OR theory could also account for near death experiences, out of body experiences, and even the afterlife.

“The connection to space–time geometry also raises the intriguing possibility that Orch OR allows consciousness apart from the brain and body, distributed and entangled in space–time geometry,” Hameroff says according to Popular Mechanics. When he spoke to the Huffington Post he also claimed, “It’s possible that the quantum information can can exist outside the body, perhaps indefinitely, as a soul.”

Skeptics have long attributed near death experiences to physical phenomena such as the brain being deprive of oxygen, not the human soul or any interaction with God or the afterlife. To put these claims in perspective, last year, even Skeptic magazine’s Michael Shermer wrote about a possible after-death communication from his grandfather-in-law. Other skeptics also tend to be committed materialists until they have their own experience.

One such skeptic was Dr. Eben Alexander, a neurosurgeon, whose neurons in his cerebral cortex were stunned to complete inactivity for seven days during a near-fatal bout of meningitis.

“I had always believed there were good scientific explanations for the heavenly out-of-body journeys described by those who narrowly escaped death,” says Alexander in aNewsweek article. “In the fall of 2008,… I experienced something so profound that it gave me a scientific reason to believe in consciousness after death…. It exists, and what I saw and learned there has placed me quite literally in a new world: a world where we are much more than our brains and bodies, and where death is not the end of consciousness but rather a chapter in a vast, and incalculably positive, journey.”

Many Christians have come forward in recent years claiming to have experienced heaven and met God. Of course, Hameroff’s personal beliefs are very much different from traditional religions in regards to the nature of the human soul. He believes “consciousness, or its immediate precursor proto-consciousness, has been in the universe all along, perhaps from the Big Bang.”

What do you think about this quantum theory of consciousness? Do you think science will be able to prove the existence of the human soul?

Inflammation

from huffpost

‘Inconsolable’ Bobby Brown Praying for Daughter to Regain Consciousness

from time  



TIME Staff 1:06 AM ET

Bobbi Kristina Brown has been unconscious since Saturday

Family members of Bobbi Kristina Brown, the 21-year-old daughter of Whitney Houston and Bobby Brown, are waiting for a “miracle” as she remains on a respirator with scant brain activity. Brown was found unconscious Saturday in her bathtub at her home in Roswell, Ga., reports a PEOPLE exclusive.

“This is [Bobby’s] worst nightmare,” a family source told PEOPLE. “Losing Whitney [Houston] was hard, but this is a million times worse, and to lose her in the same way would devastate him.”

Read PEOPLE’s coverage here.