February 2, 2011

Brain Waves and Meditation

From: ScienceDaily.com

Forget about crystals and candles, and about sitting and breathing in awkward ways. Meditation research explores how the brain works when we refrain from concentration, rumination and intentional thinking. Electrical brain waves suggest that mental activity during meditation is wakeful and relaxed.

“Given the popularity and effectiveness of meditation as a means of alleviating stress and maintaining good health, there is a pressing need for a rigorous investigation of how it affects brain function,” says Professor Jim Lagopoulos of Sydney University, Australia. Lagopoulos is the principal investigator of a joint study between his university and researchers from the Norwegian University of Science and Technology (NTNU) on changes in electrical brain activity during nondirective meditation.

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January 26, 2011

How Brain Activity is Linked to Sleep

From: PsychCentral.com

Brain activity during times of wakefulness affects sleep and sleep quality. While researchers have been aware of this for some time, a clear understanding of how the mechanisms triggering sleep occur has remained largely unknown.

Now, a recent study has uncovered valuable insight into how the changeover from wakefulness to sleep occurs. This discovery potentially paves the way for a host of breakthroughs that could affect everything from sleeping aids to treatments for stroke and brain injury.

Led by James Krueger, Ph.D, Washington State University, the findings were recently published in the Journal of Applied Physiology and represent the most significant discovery of Krueger’s 36-year career focused on sleep research.

The study centered on a hypothesis that the major energy currency of the cell — ATP (adenosinetriphosphate) — is a key trigger for brain activity leading up to sleep. Specifically, researchers followed the method behind how ATP assists in the release of cytokines, the regulatory proteins for sleep.

“We know that brain activity is linked to sleep, but we’ve never known how,” Krueger said. “This gives us a mechanism to link brain activity to sleep. This has not been done before.”

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November 6, 2010

Long-term Memories The Good, the Bad, and the Ugly

From The Dana Foundation

Editor’s note: Traumatic memories haunt the lives of people suffering from post-traumatic stress disorder, or PTSD, and other illnesses. Fortunately, recent research into the changeability of long-term memories may someday develop into treatments for such individuals. But before this can happen, writes Cristina Alberini, Ph.D., of Mount Sinai School of Medicine, researchers must determine just how effectively the fear associated with older memories—especially those involved in PTSD—can be reduced and for how long. Researchers must also address the ethical issues that go hand in hand with modifying memory.

For more than a century, clinicians, psychologists, and biologists have worked to understand the mechanisms underlying the formation and storage of long-term memories. Recently, scientists found that when a stored memory is recalled, it becomes sensitive to disruption for a limited time.1,2 This finding indicates that it might be possible to weaken or even erase memories of traumatic experiences that become uncontrollably intrusive in post-traumatic stress disorder (PTSD). This possibility has drawn great interest from scientific and clinical communities, as well as from nonscientists, who became interested in its potential clinical applications; furthermore, it raised ethical concerns.

Many ethical questions and debates about treatments designed to weaken memories may reflect the still poor understanding of how memory recall or reactivation results in memory fragility and the many unknowns surrounding its temporal boundaries. Whereas the study of animal models and healthy humans has provided some knowledge about post-recall memory disruption, data on the use of such disruption to treat PTSD symptoms are still conflicting. The strengthening of memory with the passage of time, the resilience of strong memories to disruption, and the specific aspects of memory that become sensitive to disruption raise questions about the limitations of this approach and warrant more research. Here, we will look at how we form memories of an emotional event and how these memories become fragile after recall. That will help us consider the potential, limitations, and ethics of disrupting memories of emotion.

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November 4, 2010

Why Animals Are Biologically Conscious. The conscious brain has a long evolutionary history.

From: The Blog of Dr. Bernard J. Baars inPsychology Today

To the best of our knowledge, consciousness depends upon brains, and brains are biological organs. In a boxing match, a blow to the jaw often leads to a loss of consciousness, but the same impact to the torso does not. More specifically, scientists have long thought that human consciousness depends upon two large brain structures, the cortex and the thalamus. The daily cycle of waking, dreaming and sleep depends on distinctive global rhythm generators in the thalamus and cortex. (www.baars-gage.com, Chapter 8)

While deep brain nuclei control the daily sleep-waking cycle, the specific contents of conscious vision, like the sight of a coffee cup, are directly supported by known regions of the cortex and corresponding nuclei in the thalamus. Cortex and its satellites underlie speech and hearing, vision, hearing and touch, the ability to make decisions and to control our voluntary muscles.

In contrast, medical students have long learned that the two large lobes of the cerebellum, hanging from the rear of the cortex, can be damaged in humans without impairing consciousness significantly. Since the cerebellum has nearly the same numbers of neurons as cortex, the question therefore becomes: How it is that cortex supports conscious contents? Why not the cerebellum? (Figure 1).

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December 11, 2007

The trivial function of sleep

Rest in poikilothermic animals is an adaptation of the organism to adjust to the geophysical cycles, a doubtless valuable function for all animals. In this review, we argue that the function of sleep could be trivial for mammals and birds because sleep does not provide additional advantages over simple rest. This conclusion can be reached by using the null hypothesis and parsimony arguments.

First, we develop some theoretical and empirical considerations supporting the absence of specific effects after sleep deprivation. Then, we question the adaptive value of sleep traits by using non-coding DNA as a metaphor that shows that the complexity in the design is not a definitive proof of adaptation.

We then propose that few, if any, phenotypic selectable traits do exist in sleep. Instead, the selection of efficient waking has been the major determinant of the most significant aspects in sleep structure. In addition, we suggest that the regulation of sleep is only a mechanism to enforce rest, a state that was challenged after the development of homeothermy.

As a general conclusion, there is no direct answer to the problem of why we sleep; only an explanation of why such a complex set of mechanisms is used to perform what seems to be a simple function. This explanation should be reached by following the evolution of wakefulness rather than that of sleep. Sleep could have additional functions secondarily added to the trivial one, although, in this case, the necessity and sufficiency of these sleep functions should be demonstrated.

The trivial function of sleep. R.V. Rial, Maria C. Nicolau, Antoni Gamundi, Mourad Akaarir, Sara Aparicio, Celia Garau, Silvia Tejada, Catalina Roca, Lluis Gene, David Moranta, Susana Esteban, 2007. Sleep Medicine Reviews 11(4):311-325.

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October 18, 2007

Dream content: Individual and generic aspects

Dream reports were collected from normal subjects in an effort to determine the degree to which dream reports can be used to identify individual dreamers. Judges were asked to group the reports by their authors. The judges scored the reports correctly at chance levels. This finding indicated that dreams may be at least as much like each other as they are the signature of individual dreamers. Our results suggest that dream reports cannot be used to identify the individuals who produced them when identifiers like names and gender of friends and family members are removed from the dream report. In addition to using dreams to learn about an individual, we must look at dreams as telling us about important common or generic aspects of human consciousness.next term

Allan Hobson and David Kahn in press article in Consciousness & Cognition

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Dreaming: New issue

altered states,dreaming,journal — thomasr @ 3:43 am

A new issue of Dreaming is out, covering topics such as dreaming and physical health, insomnia and dream content, and personality types.

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September 12, 2007

The biology of sleep

dreaming,journal,meds,sleep — thomasr @ 1:47 pm

sleep.jpegMedscape is running a special topic edition on the biology of sleep. The articles include papers on the management of insomnia; the relationship between passive sleeping and sleep disturbance during pregnancy; and the effects of hypothalamic stimulation on cluster headache and sleep.

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September 3, 2007

Birth and sleep content

altered states,development,dreaming — thomasr @ 3:33 am

pregnant.jpegThe conception and birth of a child are emotional events that influence the dreams of most new mothers. In a surprisingly high number of cases, this influence reflects negative aspects of maternal responsibility, depicting the new infant in dreamed situations of danger and provoking anxiety in the mother that often spills over into wakefulness. Furthermore, these kinds of dreams are also accompanied by complex behaviors by new moms such as motor activity, speaking and expressing emotion, according to a study published in the September 1 issue of the journal SLEEP.

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July 5, 2007

New issue: Dreaming

altered states,dreaming,journal — thomasr @ 3:57 am

A new issue of Dreaming is out, including articles on emotion, culture, and the self. Here we bring the abstracts

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