MindMods Blog

  1. EEG coherence effects of audio-visual stimulation (AVS)

    at dominant and twice dominant alpha frequency

     

    EEG coherence effects of audio-visual stimulation (AVS) at dominant and twice dominant alpha frequency



    eeg coherence


     

    Jon A. Frederick, Ph.D.* DeAnna L. Timmermann, Ph.D.** Harold L. Russell, Ph.D.*** Joel F. Lubar, Ph.D.****

     

    Journal of Neurotherapy, In Press

     

    *Corresponding author. Center for Computational Biomedicine, University of Texas Houston Health Science Center, 7000 Fannin Suite 600, Houston, TX 77030. (713) 500-3464, email: smiile@psynet.net

    **Department of Psychology, Eastern Oregon University, One University Avenue, LaGrande, OR 97850.

    ***P.O. Box 240, Galveston, TX, 77553.

    ****Department of Psychology, University of Tennessee, 307 Austin Peay, Knoxville, TN 37996.



    SUMMARY. The effects of a single session of audio-visual stimulation (AVS) at the dominant alpha rhythm and twice-dominant alpha frequency on EEG coherence were studied in 23 subjects. An eyes-closed baseline EEG determined each subject's dominant alpha frequency. Subjects were stimulated at their dominant alpha frequency or at twice dominant alpha frequency for twenty minutes, while EEG was recorded in 5-minute intervals. A post-session baseline was recorded 30 minutes after each session. AVS decreased coherence in the intrahemispheric projections from the occipital region and the parietal midline, and generally increased coherence, with few exceptions, among all other longitudinal pairs. Interhemispheric coherence increased posteriorily and high frequencies, and tended to decrease frontally and low frequencies. Alpha AVS was more effective than twice-alpha AVS at producing interhemispheric synchronization, and tended to produce more effects overall. Although main effects of frequency and time were observed, when individual coherence pairs changed, they almost always changed in only one direction. Overall coherence was greater during the first ten minutes than the last ten minutes, and greatest in the beta 1 and delta 2 bands, and lowest in the alpha and delta 1 bands. Few, if any, significant effects persisted into the post-stimulation baseline. A new method of assessing the effects of multiple comparisons on experimentwise error, based on randomization theory, is proposed and implemented.


    Click 'Read More' below for the rest


    INTRODUCTION

    The ability of a flashing light stimulus to evoke EEG rhythms related to the stimulus frequency has been studied since the early history of electroencephalography (Adrian & Matthews, 1934). Known as the photic driving response (PDR), or steady state visual evoked potential, this effect is commonly measured in routine clinical EEG examinations, and has been proven useful for investigating neurological disorders (Takahashi, 1987; Coull & Pedley, 1978; Duffy, Iyer, & Surwillo, 1989).


    The diverse perceptual and emotional effects of photic stimulation (Walter & Walter, 1949; Stwertka, 1993; Gizycki, Jean-Louis, Snyder, Zizi, Green et al., 1998), and it’s ability to cause seizures in susceptible individuals (Walter, Dovey & Shipton, 1946; Striano, Meo, Bilo, Ruosi, Soricellis et al., 1992) have led many to investigate whether rhythmic auditory and visual stimulation (AVS) might also induce clinically beneficial changes in brain activity. In the 1950’s and 60’s, many studies focused on the ability of AVS to induce relaxation and hypnosis (reviewed in Morse, 1993). Others have reported AVS to be effective for relieving a diversity of pain symptoms (Solomon, 1985; Anderson, 1989; Shealy, Cady, Cox, Liss et al., 1990), treating dental anxiety (Morse, 1993), premenstrual syndrome (Noton, 1997), fibromyalgia (Mueller, Donaldson, Nelson & Layman, 2001) and for alleviating the cognitive dysfunctions associated with closed head injury (Montgomery, Ashley, Burns & Russell, 1994) and strokes (Russell, 1997; Rozelle & Budzinski, 1995). Since the enhancement of beta (13-21 Hz) and inhibition of theta (4-8 Hz) is a goal of EEG biofeedback for the treatment of attention deficit hyperactivity disorder (ADHD; Lubar & Lubar, 1999; Lubar, Swartwood, Swartwood & O’Donnell, 1995), some have proposed using AVS in neurofeedback as a “priming stimulus” to encourage the endogenous production of desired cortical frequencies, which are then reinforced as the conditioned response. In a study of 25 ADHD children, Patrick (1996) found “photic-driven EEG neurotherapy” effective in improving cognitive, behavioral, and clinical EEG measures in less than half the number of sessions usually required. Meanwhile, Micheletti (1999) found AVS alone effective in improving cognitive and behavioral measures, in a study of 99 ADHD children. Carter and Russell (1993) reported significant improvement in cognitive and behavioral functioning, related to the number of AVS sessions, in learning disabled boys. Joyce and Siever (2000) reported that a 7-week audiovisual stimulation treatment in 8 reading-disabled children, compared to a control group, normalized scores on the Test of Variables of Attention (TOVA), improved scores on the Standardized Test for the Assessment of Reading (STAR), and improved general behavior as noted by teachers and parents.


    Mechanisms by which long-term AVS therapies may cause these behavioral changes have been suggested by research in neuronal plasticity. A number of investigators (van Praag, Kempermann & Gage, 2000; Rosenzweig, 2003; Mohammed, Zhu, Darmopil, Hjerling-Leffler, Ernfors et al., 2002) are in essential agreement that ongoing direct experience that evokes persistent neuronal activation alters brain structure and brain functioning. Although most studies have focused on effects of an enriched environment, persistent neuronal activation can also be evoked by trains of sensory stimuli. Human subjects have been shown to respond to flicker frequencies from 1-100 Hz with steady-state activity at all frequencies up to at least 90 Hz with clear resonance phenomena or harmonics at 10, 20, 40 and 80 Hz (Herrmann, 2001). A possible linkage between steady-state stimulation induced neuronal activation and neuronal plasticity is the increasing evidence that brain electrical activity regulates the synthesis, secretion and actions of neurotrophins (Schindler and Poo, 2000), which promote synaptogenesis.


    The most commonly studied PDRs have been the effects of stimulation on alpha (8-13 Hz) power over the occipital region (Iwahara, Noguchi, Yang & Oishi, 1974; Aranibar & Pfurtscheller, 1978). The photic driving response is most reliable when the stimulus approximates the subject’s peak alpha frequency (Toman, 1941; Townsend, Lubin, & Naitoh, 1975). However, recent studies have shown that AVS activates a diverse range of EEG frequencies, beyond the primary sensory cortices, and outside of the frequency of stimulation. Using low-frequency theta AVS, Dieter & Weinstein (1995) described a significant reduction in "mean activity" (an increase of delta and theta activity) in frontal, central, and parietal regions, in addition to occipital regions. In a study of 13 college students (Timmermann, Lubar, Rasey & Frederick, 1999), we found that effects of AVS were widely distributed across the standard 10-20, 19-channel montage. AVS at a subject's dominant alpha frequency had no effect in the alpha band, but significantly increased power in the delta 1, delta 2, theta, beta 1, and beta 2 bands. Stimulation at twice the dominant alpha frequency significantly increased theta, alpha, beta 1, and beta 2 power.


    While the amplitude and power effects of AVS have been widely studied, relatively little is known about the effects of AVS on EEG coherence. Coherence is a correlational measure, varying between zero and one, of the variability in phase between two signals over time (Shaw, 1981). This frequency-specific signal correlation suggests the extent to which two regions are cooperating on the same task. High coherence indicates a common signal, whether it is synchronous between two locations, or delayed by a constant conduction velocity. Coherence in the eyes-closed baseline reflects the number of synaptic connections between recording sites, and the strength of these connections (Thatcher, 1992). Coherence has been shown to be lower in Alzheimer patients, comatose subjects, and in brain-injured subjects, while it is higher in mentally retarded persons, during sleep, and during epileptic seizures. Between these extremes, "optimal levels" of coherence for normal functioning have been described (Silberstein, 1995). Some have suggested that EEG coherence biofeedback could be used to normalize the coherence deviations seen in dyslexic and head injured subjects (Evans & Park, 1996; Hoffman, Stockdale, Hicks & Schwaninger, 1995).


    Differences in photic driving of coherence have been described between normal subjects and patients with Alzheimer's disease (Wada, Nanbu, Kikuchi, Koshino, Hashimoto et al., 1998a), schizophrenia (Wada, Nanbu, Kikuchi, Koshino & Hashimoto, 1998b), and between genders (Wada, Nanbu, Kadoshima & Jiang, 1996). However, the effects of combined auditory and visual stimulation on coherence in normal subjects have not been previously reported.


    Although AVS devices are used by many neurotherapists as an adjunct to EEG biofeedback, the overall pattern of effects of AVS on coherence needs to be better understood, to ensure that AVS treatment is influencing coherence in the appropriate direction. To begin to achieve this understanding, we conducted an exploratory study of the effects of AVS on coherence in normal college students. We hypothesized that AVS would increase coherence at the frequency of stimulation, and assumed that effects would be most prominent over the occipital and temporal leads, which are closest to the primary visual and auditory cortex. Given our previous findings of increased amplitude in multiple frequency bands (Timmermann et al., 1999), we anticipated effects across the coherence spectrum. However, since our goal was to observe the effects rather than to verify any hypothesis about them, beyond the expected increase at the stimulus frequencies, we did not predict directions of change.



    The rest of this study can be found in PDF format here: http://www.mindmodulations.com/resources/Study-frederick-avs-coherence.pdf

  2. Can Freud's Theory of Dreams Hold Up Against Modern Neuroscience?

    HOBSON'S CHOICE

    Can Freud's Theory of Dreams Hold Up Against Modern Neuroscience?

    biofeedback and light and sound mind machines 


    This following is an excerpt from an article printed in 'The Believer' magazine written by Rachel Aviv. Oct 2007

    It wasn’t until the 1950s, fifty years after the publication of The Interpretation of Dreams,that scientists began bringing people into their labs for sleepovers. They’d spray water on them, or rub their faces with cotton puffs, or ring a bell and then wake them up and see what happened. Volunteers were kept up for days and watched closely, to see whether or not they’d go insane. The early experiments were crude and often conducted by psychiatrists trained in Freudian theory. One prominent researcher studied sexual dream symbols by attempting to correlate erections (he wrapped a nooselike device around the sleeper’s penis) with aggressive dream content, like dog- and snakebites, knife fights, and scenes of choking. He was able to correctly predict tumescence seven times out of eight.

    Other researchers took a sociological approach to dreams, meticulously cataloging their content: women dream of men more than men dream of women; black people are more likely to be physically damaged in their dreams than white people; 80 percent of adult dreams have a negative component—their hair looks bad or they can’t find their keys or their kid won’t stop crying—and after ninth grade, children’s dreams become significantly more aggressive.

    The field of dream research deals with the worst kind of data: reported by groggy volunteers, grasping at half-formed memories. Once you wake someone up, you’ve already interfered with the evidence. Hobson’s Activation-Synthesis model was so well received, in part, because it was based on neuroscience, not subjective reports. Rosalind Cartwright, chair of psychology at Rush University Medical Center in Chicago, who is well known for her research on how dreams affect mood, recalls first hearing Hobson propose his model at a conference in the early ’70s. “A bunch of us were sitting next to each other and we said, ‘You got it the wrong way around! We won’t let your physiological tail wave our psychological dream-dog!’ I used to say about Allan, ‘Oh the trouble is, he’s looking at cell recordings, he’s not talking to people—if he were paying attention to his own dreams, he would be smarter at it.’ When he did start paying attention to these things, I felt he modified his ideas a good deal.”

    Only in recent years has Hobson become willing to talk more about the part of dreams that most people are interested in—feelings, symbols, characters, themes. After waking up from a particularly vivid nightmare, few of us are wondering, What part of my brain was just functioning? With practice and the help of a Nightcap (a bandanna device that beeps every few hours, wakes you up, then records whatever you say about your interrupted dream), Hobson began focusing more on the softer side of his field. “I love to talk about my dreams,” he said at the consciousness conference last year. “I’m not sure any of it really makes any difference, or that I learn anything I didn’t know, but it’s a wonderful, wonderful thing to do.”

    His enthusiasm for dreams became even more pronounced when, for a startling month in 2001, he lost the ability to have them. While vacationing in Monte Carlo, Hobson suffered a stroke that affected the precise part of the brain stem that he began his career studying. He knew how his body would respond because he had done countless experiments on how damage to this area affects lab cats. He became nauseous, lost balance, and felt he was drowning in his own saliva. For eight days, he lost the ability to fall asleep. For a month, he couldn’t dream. He felt himself becoming psychotic with exhaustion. Like Freud, inventor of the talking cure, dying of oral cancer, Hobson seemed to have the perfect affliction. “I was wide awake all night long,” he recalls. “I said to myself, I am a cat. I am an experimental animal. But this is no experiment.”


    Click 'Read More' below for the rest.

    After several days without sleep, Hobson began suffering from elaborate hallucinations. In 2002, he published articles about the experience in the journals Cerebrum and Consciousness and Cognition, vividly detailing his escalating visions. Immediately upon closing his eyes, he’d imagine himself at the bottom of a swimming pool, or covered in pieces of computer paper. Later, he was deluged by images of swirling flesh: free-floating nipples, sphincters, and crotches. At one point, he saw “a Peter Pan–like version of a colleague, Robert Stickgold, and two fairies enjoying a bedtime story.”

    Hobson documented the stroke with a camera and tape recorder, dutifully noting strange thoughts, vomiting episodes, small improvements, and pain. The process reminded him of therapy, he said. Finally on the thirty-first day of his hospitalization, he had a full dream, his first in more than a month, in which his wife tried to cheat on him in forty-five minutes. Writing about the experience in multiple journals, he used the illness as a rare opportunity to provide a link between his own neurology and psychology. His doctors, however, were less interested in the connection. Hobson resented their quick and systematic diagnoses. No “doctor who saw me ever expressed any interest in what I was experiencing subjectively,” he wrote.

    For years Mark Solms has criticized the field of neuroscience for just this—ignoring personal experience, treating the mind as if it were a chemical pump. (He was drawn to neuroscience at a young age, when his younger brother became brain damaged after falling from a roof.) In the face of his own trauma, Hobson too has become increasingly open to the nuances of emotional life. His Vermont museum, which features animated dream reports and synthesized “sleep music,” is a tribute to the artistic and literary possibilities of dreaming. His late-age approach has a lot more in common with Solms’s “neuro-psychoanalysis” than either of them admit.

    After forty years of studying dreams, Hobson seems seduced again by the mysteries that originally brought him to the field. Hard science can never adequately describe that murky, intuitive feeling in the morning—the sense that you spent the night somewhere else. When Freud abandoned his Project for a Scientific Psychology, there were problems beyond primitive technology: Deconstructing a dream is about as mathematical as pinpointing the coordinates of the Garden of Eden. The fascination endures because it’s just out of reach, never fulfilled. Hobson was equipped with far more scientific knowledge than Freud could ever hope for, but he still finds himself making imaginative leaps, translating images into themes and symbols and fantasies. The concept of dreaming is born from this impulse: it’s too hard to resist a good story.

  3. Tactile-Emotion Synaesthesia


    bleeding senses into one another with jeans 


    I just saw this on the great blog 'Neuro Philosophy'.

    Two researchers from the Center for Brain and Cognition have found a rare new form of synaesthesia that they have labeled 'tactile-emotion synaesthesia'. They have found two individual cases of patients experiencing specific emotions whenever touching particular textures! The feeling of denim, in one of the cases, caused strong feelings of depression and disgust.


    Abstract:


    We discuss experiments on two individuals in whom specific textures (e.g., denim, wax, sandpaper, silk, etc.) evoked equally distinct emotions (e.g., depression, embarrassment, relief, and contentment, respectively). The test/retest consistency after 8 months was 100%. A video camera recorded subjects' facial expressions and skin conductance responses (SCR) were monitored as they palpated different textures. Evaluators' ratings significantly correlated with the valence of synesthetes' subjective reports, and SCR was significantly enhanced for negative synesthetic emotions. We suggest this effect arises from increased cross-activation between somatosensory cortex and insula for 'basic' emotions and fronto-limbic hyperactivation for more subtle emotions. It may represent an enhancement of pre-existing evolutionarily primitive interactions between touch and emotions.


    http://www.ncbi.nlm.nih.gov/pubmed/18821168

  4. Emotiv Epoc EEG Brain-Wave PC controller delayed until 2009




    The release of the much anticipated Emotiv Systems Epoc is delayed until next year, according to Big Download. They were told by a Emotiv PR representative that the device is being delayed so that it works as planned when released.

    biofeedback game emotiv epoc 

    The new release date will be sometime in 2009.


  5. Laxman Light & Sound Machine will arrive here in a week or two

     

    Mind Modulations has something new coming in from Germany:



    laxman mind machine light and sound biofeedback  

    This is the Laxman. It is the next generation of light and sound machines and is guaranteed to amaze you.

    This is an eyes-open device that projects every color in the light spectrum through ganzfeld goggles. The Laxman's (Laxmen?) audio consists of impulse frequencies, binaural beats, hemicircle sounds and professionally produced music arrangements. It allows you to embed any audio that you have into customs sessions and even doubles as a traditional MP3 player. There's a mini-SD card slot in the back to use if you need extra space.


    Features:

    NextGen technology capable of producing the most profoundly amazing experiences you’ve ever had with a mind machine

    Upload your own music tracks to the Laxman for neurologically effective visual structures that match your favorite songs

    A synergy between the ganzfeld field effect and the all-color open-eye goggles. This is another dimension of entrainment.

    Fully functional MP3 Player

    SD Card memory expansion slot for sessions and music

    Intuitive menu control on LCD screen

    Four hours of exclusive ambient music and sounds

    LaxEdit Software makes creating and editing sessions simple and fun

    22 pre-installed 20 minute sessions organized by beta, alpha, theta, & delta

    USB interface for easy connectivity

    mind modulations laxman light and sound mind machine 


    We're expecting them to arrive within two weeks. You can pre-order the Laxman now on our web site:
    http://www.mindmodulations.com/prod-neurotronics-laxman-mind-machine.html

    More to come...
  6. Two papers on ganzfeld hallucinations

    ganzfeld effect  

    I found a couple of interesting articles while researching the 'Ganzfeld Effect', both involving Peter Pütz.

    The first study, done in 2005, found EEG correlates to ganzfeld induced hallucinatory imagery. The second, published in Jun 2008, is more generalized. It is entitled "Ganzfeld-induced hallucinatory experience, its phenomenology and cerebral electrophysiology"

    Unfortunately I can't post them here in their entirety, but here's the abstracts:


    Ganzfeld-induced hallucinatory experience, its phenomenology and cerebral electrophysiology

    Abstract

    Ganzfeld, i.e., exposure to an unstructured, uniform stimulation field, elicits in most observers pseudo-hallucinatory percepts, and may even induce global functional state changes (‘altered states of consciousness’). The present paper gives a comprehensive overview of the phenomenology of subjective experience in the ganzfeld and its electrophysiological correlates. Laboratory techniques for visual or multi-modal ganzfeld induction are explained. The spectrum of ganzfeld-induced phenomena, ranging from elementary percepts to complex, vivid, dream-like imagery is described, and the latter illustrated by transcripts of subjects' reports. Similarities and differences to related sensory/perceptual phenomena are also discussed. Earlier findings on electrophysiological correlates of the ganzfeld are reviewed. Our own studies of electroencephalographic (EEG) activity in the ganzfeld are presented in some detail, and a re-analysis of data on EEG correlates of hallucinatory percepts in statu nascendi is reported. The results do not support the hypothesis of the hypnagogic origin of the percepts; the ganzfeld-induced steady-state is an activated state, and the spectral EEG dynamics in the alpha frequency range reveals processes of attention shifts and percept formation. The final section is devoted to the controversial topic of allegedly anomalous communication between human subjects (‘ganzfeld telepathy’). It is shown that the use of ganzfeld in this research field relies partly on unsupported hypotheses concerning ganzfeld-induced states, partly on a weak conceptual background of the experimental procedure. The rôle of a particular belief system shared by the participants and experimenters is critically discussed.

    Jiří Wackermann, Peter Pütz, Carsten Allefeld

    Department of Empirical and Analytical Psychophysics, Institute for Frontier Areas of Psychology and Mental Health, Freiburg i. Br., Germany.


    EEG correlates of multimodal ganzfeld induced hallucinatory imagery.

    Abstract
    Multimodal ganzfeld (MMGF) frequently induces dreamlike, pseudo-hallucinatory imagery. The aim of the study was to explore EEG correlates of MMGF-induced imagery. In a screening phase, seven 'high-responders' were selected by frequency and quality of their reported hallucinatory experience in MMGF. Each of these subjects then participated in three MMGF sessions (45 min) with simultaneous 19 channel EEG recordings and indicated occurrences of imagery by pressing a button. Relative spectral power changes during percept formation (30 s preceding subjects' reports) with respect to intra-individual baselines (no-imagery EEG) were analysed. At the beginning of the 30-s 'image formation' period alpha was slightly reduced than in the 'no-imagery' periods. This was followed by increased power in the higher alpha frequency band (10-12 Hz) which then declined in a monotonic fashion. This decline in higher alpha power was accompanied by increased power in the beta frequency bands. Throughout the image formation period there was a steady decline in power of low frequency alpha (8-10 Hz). Correlations between descriptors of subjective experience and EEG power changes were evaluated in terms of their global average magnitude and variability in time. Results indicate that the acceleration of alpha activity is a nonspecific effect of MMGF. In contrast, the tri-phasic profile of faster alpha activity seems to be a specific correlate of the retrieval and transformation of memory content in ganzfeld imagery.

    Peter Pütz, MatthiasBraeunig, Jiří Wackermann

    Department of Empirical and Analytical Psychophysics, Institute for Frontier Areas of Psychology, Wilhemstrasse 3a, D-79098 Freiburg i. Br., Germany.



  7. Excellent new study on Mind Machines / Brainwave Entrainment

    A systematic review and analysis of 20 of the major studies done on Brainwave Entrainment. The effect of photic stimulation (Mind Machines) on cognition, stress & anxiety, pain, headaches & migraines, mood, and PMS are are all discussed.

    Below you'll find a link to the entire article and a conclusion extract. One of the authors of the study, Christine Charyton, PhD, is an employee of Transparent Corporation.

    Comprehensive Review of the Psychological Effects of Brainwave Entrainment

    Tina L. Huang, PhD; Christine Charyton, PhD

    From _Alternative_ Therapies, Sep/Oct 2008, Vol. 14, No. 5

    The immediate psychological effects of memory, attention, stress, pain, and headaches/migraines were shown to benefit from even a single session of BWE. Many practitioners and developers of BWE tools believe that repeated exposure to BWE will allow the user to enter the desired brain states unassisted. Indeed, the study by Patrick, which found improvements in overall intelligence and behavior, gradually withdrew the stimulus until users could produce the targeted brainwave frequencies on their own. Most studies that examined long-term effects did not withdraw stimulus over a specified time period before testing, so the duration of the effects are unclear. Nor are there studies that compare the effects of duration or frequency of stimulation, so it is not known whether there is a minimal length or frequency of entrainment required to achieve each positive outcome or if there is a limit to the intensity of symptom relief from BWE.

    ...

    Further studies are needed to compare the effects of auditory, photic, and AVE stimulation at the same frequencies for each outcome and to compare the clinical benefi ts of monaural, binaural, and isochronic beats and the use of white noise vs music as a background.

    ...

    In conclusion, preliminary evidence suggests that BWE is effective in several cognitive domains and can relieve acute and long-term stress, reduce pain, headaches, migraines, and PMS and improve behavior.

    ...

    Preliminary evidence suggests that alpha stimulation was preferable for trigram recognition, short-term stress, and pain relief, whereas beta was used to enhance attention, increase overall intelligence, relieve short-term stress, and improve behavior. The alternating alpha and beta protocol was used successfully to improve behavior, verbal skills, and attention. A protocol that alternatively ascended and descended from beta to gamma enhanced arithmetic skills and attention. A protocol that alternated between 14 and 22 Hz increased overall intelligence. Several protocols, including a combination of theta and delta and a progressive slowing over 30 minutes to delta, were effective in relieving short-term stress. Migraines were prevented with a 30-Hz stimulus that alternated between left and right hemispheres, and a few studies that allowed the subject to choose the frequency of stimulation were successful in alleviating long-term stress, pain, and migraines. It is clear that more research needs to be conducted to confi rm the effectiveness of specific protocols to each outcome, but given the evidence so far, we conclude that BWE is worthy of further consideration by clinicians and researchers as a therapeutic tool.

    Original article is here

  8. Scientists digitally reconstruct images from inside the mind?

    I can't verify this because it is in Japanese. Original article here: http://www.chunichi.co.jp/article/national/news/CK2008121102000053.html


     


    Researchers from Japan's ATR Computational Neuroscience Labs have created a new brain analysis technology that can recontruct images inside of a person's mind and then display them on a monitor. The researchers want to try to view the contents of dreams in the future.


    Sounds like either the journalist or the scientist is exaggerating their findings, but I could be wrong. I just have a hard time believing this could be possible. Here's how they are claiming to do it:

    'The scientists were able to reconstruct various images viewed by a person by analyzing changes in their cerebral blood flow. Using a functional magnetic resonance imaging (fMRI) machine, the researchers first mapped the blood flow changes that occurred in the cerebral visual cortex as subjects viewed various images held in front of their eyes. Subjects were shown 400 random 10 x 10 pixel black-and-white images for a period of 12 seconds each. While the fMRI machine monitored the changes in brain activity, a computer crunched the data and learned to associate the various changes in brain activity with the different image designs.


     

     

    Then, when the test subjects were shown a completely new set of images, such as the letters N-E-U-R-O-N, the system was able to reconstruct and display what the test subjects were viewing based solely on their brain activity.'

    The researchers also discuss applying the technology to reading feelings and complicated emotional states, but may have a difficult time displaying these things on a monitor.

    The blog 'Pink Tentacle' says that this research is in the December 11 issue 'Neuron', but I haven't been able to find it.

    lolwut?  more later...
    Update - this is being reported about all over the place now. Scientific American also uses Pink Tentacle as a source, but claim that the scientists have 'reported it' to the journal 'Neuron', not that 'Neuron' has published anything about it. Big difference. We'll see where this goes.

  9. Hack Your Brain

    I found the below images while reading the Boston Globe.  (Boston Globe?!)

    These are great little examples of how you can trick your senses into perceiving things that you know are not real.  The experiences produced by the experiments are something much like hallucinations.

     

    Try them out for yourself! 

     

    The Ganzfeld Procedure

     The Ganzfeld Procedure

     

    Incredible Shrinking Pain

     Incredible Shrinking Pain

     

    The Rubber Hand Illusion

     Rubber Hand Illusion
    ;Rubber Hand Illusion

     

    The Pinocchio Illusion

     Pnocchio Illusion

     

    Purkinje Lights

     Purkinje Lights

     

     

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7:05am April 19-5:00 GMT