Nav: Home

Brain patterns indicative of consciousness, in unconscious individuals

February 06, 2019

Amid longstanding difficulties distinguishing consciousness in humans in unconscious states, scientists report fMRI-based evidence of distinct patterns of brain activity they say can differentiate between consciousness or unconsciousness. Detecting these patterns in real-time could allow for externally induced manipulations that noninvasively restore consciousness. The detection process also has the potential to greatly facilitate medical decision-making for patients in whom consciousness is impaired, the authors say. Unconsciousness is characterized by an inability to report subjective experience. For patients induced into temporary unconsciousness via pharmacological agents such as anesthetics, or for those in a more enduring state of unconsciousness caused by brain injury, reliable markers indicating presence or absence of consciousness have been elusive. In search of such indicators, A. Demertzi and colleagues recorded functional magnetic resonance imaging (fMRI) data from 159 subjects scanned at four independent research sites. Some among these were healthy patients who had undergone anesthesia. The others, assessed through standardized behavioral assessments, were patients diagnosed as having either unresponsive wakefulness syndrome (UWS) - in which they can open their eyes but do not display voluntary movements - or as being in a minimally conscious state (MCS) - in which they show additional behaviors potentially indicative of awareness. The authors analyzed how fluctuations of the fMRI blood oxygenation level-dependent (BOLD) signal - a proxy for neuronal activity - were coordinated across 42 key brain regions representing six brain networks known to play an important role in cognition. The analysis uncovered four distinguishable patterns: pattern 1 was highly complex, with long-distance brain-wide coordination between regions. It was seen more often in healthy, conscious people. Pattern 4, on the other hand, showed low interareal coordination and was most apparent in UWS patients. Demertzi and colleagues found that anesthetized patients displayed a lower probability or transitioning between different brain states over time. These findings provide insight into the large-scale brain dynamics that support conscious behavior - suggesting that highly complex, long-distance brain-wide coordination is a key characteristic of consciousness - and they offer important clues in the search for biological markers of consciousness, say the authors.
-end-


American Association for the Advancement of Science

Related Brain Activity Articles:

More brain activity is not always better when it comes to memory and attention
Potential new ways of understanding the cause of cognitive impairments, such as problems with memory and attention, in brain disorders including schizophrenia and Alzheimer's are under the spotlight in a new research review.
Researchers to predict cognitive dissonance according to brain activity
A new study by HSE researchers has uncovered a new brain mechanism that generates cognitive dissonance -- a mental discomfort experienced by a person who simultaneously holds two or more contradictory beliefs or values, or experiences difficulties in making decisions.
Brain activity can be used to predict reading success up to 2 years in advance
By measuring brainwaves, it is possible to predict what a child's reading level will be years in advance, according to research from Binghamton University, State University of New York.
There's a close association between magnetic systems and certain states of brain activity
Scientists from the University of Granada (UGR) have proven for the first time that there is a close relationship between several emerging phenomena in magnetic systems (greatly studied by condensed matter physicists) and certain states of brain activity.
Hormone can enhance brain activity associated with love and sex
The hormone kisspeptin can enhance activity in brain regions associated with sexual arousal and romantic love, according to new research.
Manipulating brain activity to boost confidence
Is it possible to directly boost one's own confidence by directly training the brain?
Brain activity may predict risk of falls in older people
Measuring the brain activity of healthy, older adults while they walk and talk at the same time may help predict their risk of falls later, according to a study published in the Dec.
Neuro chip records brain cell activity
In order to understand how the brain controls functions, such as simple reflexes or learning and memory, we must be able to record the activity of large networks and groups of neurons.
Too much activity in certain areas of the brain is bad for memory and attention
Researchers led by Dr Tobias Bast in the School of Psychology at The University of Nottingham have found that faulty inhibitory neurotransmission and abnormally increased activity in the hippocampus impairs our memory and attention.
Brain changes after menopause may lead to lack of physical activity
Researchers from the University of Missouri have found a connection between lack of ovarian hormones and changes in the brain's pleasure center, a hotspot in the brain that processes and reinforces messages related to reward, pleasure, activity and motivation for physical exercise.

Related Brain Activity Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Anthropomorphic
Do animals grieve? Do they have language or consciousness? For a long time, scientists resisted the urge to look for human qualities in animals. This hour, TED speakers explore how that is changing. Guests include biological anthropologist Barbara King, dolphin researcher Denise Herzing, primatologist Frans de Waal, and ecologist Carl Safina.
Now Playing: Science for the People

#SB2 2019 Science Birthday Minisode: Mary Golda Ross
Our second annual Science Birthday is here, and this year we celebrate the wonderful Mary Golda Ross, born 9 August 1908. She died in 2008 at age 99, but left a lasting mark on the science of rocketry and space exploration as an early woman in engineering, and one of the first Native Americans in engineering. Join Rachelle and Bethany for this very special birthday minisode celebrating Mary and her achievements. Thanks to our Patreons who make this show possible! Read more about Mary G. Ross: Interview with Mary Ross on Lash Publications International, by Laurel Sheppard Meet Mary Golda...