Don't Lose Your Head Over tDCS
Recent studies of transcranial electrical stimulation in human cadaver heads showed a 90% loss of current when delivered through the skin (Buzsáki, 2016 CNS meeting).Siren SongBy Margaret AtwoodThis is the one song everyone would like to learn: the songthat is irresistible:the song that forces mento leap overboard in squadronseven though they see the beached skullsthe song nobody knowsbecause anyone who has heard itis dead, and the others can't remember.Better living through electricity. The lure of superior performance, improved memory, and higher IQ without all the hard work. Or at least, in a much shorter amount of ti...
Source: The Neurocritic - April 13, 2016 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
Sleep Doctoring: Fatigue Amnesia in Physicians
New in the journal journal Cortex: four shocking cases of practicing medicine while exhausted (Dharia & Zeman, 2016). The authors called this newly discovered syndrome “fatigue amnesia.” Why this is is any different from countless other examples of not remembering things you did while exhausted — I do not know. Except amnesia for performing a complex medical procedure is a lot more disturbing than forgetting you did the dishes the night before.Here are the cases in brief:Case 1: A consultant geriatrician, while working as house officer, treated a patient with chest pain and severe pulmonary oedema in ...
Source: The Neurocritic - March 30, 2016 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
Everybody Loves Dopamine
This study showed that rats who like to “gamble” on getting a larger sucrose reward have a weaker neural response after “losing.” In this case, losing means choosing the risky lever, which dispenses a low amount of sucrose 75% of the time (but a high amount 25%), and getting a tiny reward. The gambling rats will continue to choose the risky lever after losing. Other rats are risk-averse, and will choose the “safe” lever with a constant reward after losing.This paper was a technical tour de force with 14 multi-panel figures.1 For starters, cells in the nucleus accumbens (a VTA target) expressing the D2 receptor...
Source: The Neurocritic - March 26, 2016 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
A Detached Sense of Self Associated with Altered Neural Responses to Mirror Touch
Our bodily sense of self contributes to our personal feelings of awareness as a conscious being. How we see our bodies and move through space and feel touched by loved ones are integral parts of our identity. What happens when this sense of self breaks down? One form of dissolution is Depersonalization Disorder (DPD).1 Individuals with DPD feel estranged or disconnected from themselves, as if their bodies belong to someone else, and “they” are merely a detached observer. Or the self feels absent entirely. Other symptoms of depersonalization include emotional blunting, out-of-body experiences, and autoscopy.Autoscop...
Source: The Neurocritic - March 19, 2016 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
Writing-Induced Fugue State
Who is this, wandering around the crowded street, afraid of everything, trusting no one? “There must be something wrong, somewhere.”But maybe I’m safer since I look disheveled. Who are these people? Where is this place?Did I write that? When did that happen? I don’t remember. I can’t stop writing. I can’t stop walking, either, which is a problem because it’s hard to write and walk at the same time.In the early 1940s, Austrian Psychiatrist Dr. Erwin Stengel wrote a pair of papers on fugue states, a type of dissociative disorder involving loss of personal identity and aimless wandering (Stengel, 1941):THE pec...
Source: The Neurocritic - March 6, 2016 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
The Brain at Rest
As you might have gathered, my brain is taking a rest from blogging after the excitement of The Neurocritic's tenth anniversary. Regular blogging will resume shortly.Thank you for your patience. Fig. 1 (Buckner, 2013). The brain's default network. The default network was discovered serendipitously when experimenters using neuroimaging began examining brain regions active in the passive control conditions of their experiments. The image shows brain regions more active in passive tasks as contrast to a wide range of simple, active task conditions.6 Dialogues Clin Neurosci. 2013 Sep; 15(3): 351–358. (Source: The Neurocritic)
Source: The Neurocritic - February 20, 2016 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
Was I Wrong?
In honor of The Neurocritic's 10th anniversary, I'd like to announce a new occasional feature:Was I Wrong? In science, as in life, we learn from our mistakes. We can't move forward if we don't admit we were wrong and revise our entrenched theory (or tentative hypothesis) when faced with contradictory evidence. Likewise, it's possible that some of the critiques in this blog are no longer valid because additional evidence shows that the authors were correct. And vindicated. At least for now...I've been collecting possible instances of this phenomenon for months, and I'll preview two of these today.(1) In November 2015, I s...
Source: The Neurocritic - January 30, 2016 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
How do you celebrate 10 years of an anonymous blog?
Today, The Neurocritic celebrates ten years as a blog. Given the ongoing use of a pseudonym, how should I commemorate the occasion?1. Should I finally update my blog template? (“Hey, 2004 wants their Blogger template back”).2. Should I throw a party? Popular London-based blogs Mind Hacks and BPS Research Digest held big public bashes in November 2014 and December 2015, respectively. My audience is only a fraction of theirs, however. I doubt a local gathering of fans would fill more than a broom closet.3. How about a Happy Hour, where I privately invite social media folks who live nearby? I know where many of you ...
Source: The Neurocritic - January 26, 2016 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
This Neuroimaging Method Has 100% Diagnostic Accuracy (or your money back)
doi:10.1371/journal.pone.0129659.g003Did you know that SPECT imaging can diagnose PTSD with 100% accuracy (Amen et al., 2015)? Not only that, out of a sample of 397 patients from the Amen Clinic in Newport Beach, SPECT was able to distinguish between four different groups with 100% accuracy! That's right, the scans of (1) healthy participants, and patients with (2) classic post-traumatic stress disorder (PTSD), (3) classic traumatic brain injury (TBI), and (4) both disorders..... were all classified with 100% accuracy!TRACK-TBI investigators, your 3T structural and functional MRI outcome measures are obsolete.NIMH, t...
Source: The Neurocritic - January 21, 2016 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
Opioid Drugs for Mental Anguish: Basic Research and Clinical Trials
The prescription opioid crisis of overdosing and overprescribing has reached epic proportions, according to the North American media. Just last week, we learned that 91% of patients who survive opioid overdose are prescribed more opioids! The CDC calls it an epidemic, and notes there's been “a 200% increase in the rate of overdose deaths involving opioid pain relievers and heroin.” A recent paper in the Annual Review of Public Health labels it a “public health crisis” and proposes “interventions to address the epidemic of opioid addiction” (Kolodny et al., 2015).In the midst of this public and professional outc...
Source: The Neurocritic - January 7, 2016 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
Social Pain Revisited: Opioids for Severe Suicidal Ideation
Does the pain of mental anguish rely on the same neural machinery as physical pain? Can we treat these dreaded ailments with the same medications? These issues have come to the fore in the field of social/cognitive/affective neuroscience.As many readers know, Lieberman and Eisenberger (2015) recently published a controversial paper claiming that a brain region called the dorsal anterior cingulate cortex (dACC, shown above) is “selective” for pain.1 This finding fits with their long-time narrative that rejection literally “hurts” — social pain is analogous to physical pain, and both are supported by activity ...
Source: The Neurocritic - December 28, 2015 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
This Week in Neuroblunders: fMRI Edition
My entire body of work has been called into question!And what a fine week for technical neurogaffes it is. First was the threat that many trendy and important studies of neural circuits may need to be replicated using old-fashioned lesion methods, because of “off-target” effects:Where do we go from here? Most acute manipulation studies that use optogenetics confirm, and so add valuable support to, existing hypotheses that were established in earlier studies. But for those studies that have proposed new circuit functions, it may be advisable to re-evaluate the conclusions using independent approaches.1 Up next we have.....
Source: The Neurocritic - December 12, 2015 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
This Week in Neuroblunders: Optogenetics Edition
Recent technological developments in neuroscience have enabled rapid advances in our knowledge of how neural circuits function in awake behaving animals. Highly targeted and reversible manipulations using light (optogenetics) or drugs have allowed scientists to demonstrate that activating a tiny population of neurons can evoke specific memories or induce insatiable feeding.But this week we learned these popular and precise brain stimulation and inactivation methods may produce spurious links to behavior!! And that “controlling neurons with light or drugs may affect the brain in more ways than expected”! Who knew that r...
Source: The Neurocritic - December 11, 2015 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
Carving Up Brain Disorders
Neurology and Psychiatry are two distinct specialties within medicine, both of which treat disorders of the brain. It's completely uncontroversial to say that neurologists treat patients with brain disorders like Alzheimer's disease and Parkinson's disease. These two diseases produce distinct patterns of neurodegeneration that are visible on brain scans. For example, Parkinson's disease (PD) is a movement disorder caused by the loss of dopamine neurons in the midbrain.Fig. 3 (modified from Goldstein et al., 2007). Brain PET scans superimposed on MRI scans. Note decreased dopamine signal in the putamen and substantia nigra ...
Source: The Neurocritic - November 28, 2015 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
Happiness Is a Large Precuneus
What is happiness, and how do we find it? There are 93,290 books on happiness at Amazon.com. Happiness is Life's Most Important Skill, an Advantage and a Project and a Hypothesis that we can Stumble On and Hard-Wire in 21 Days.The Pursuit of Happiness is an Unalienable Right granted to all human beings, but it also generates billions of dollars for the self-help industry.And now the search for happiness is over! Scientists have determined that happiness is located in a small region of your right medial parietal lobe. Positive psychology gurus will have to adapt to the changing landscape or lose their market edge. “My se...
Source: The Neurocritic - November 21, 2015 Category: Neuroscience Authors: The Neurocritic Source Type: blogs
