Science is always coming up with new wonders to behold. If there is an ill that needs curing–trust me–someone is doggedly pursuing the solution. I also get the sense when reading the news that these intrepid pursuits are constantly returning fruitful results.
But science rarely undertakes rapid progress like this. Most discoveries are slow, painstakingly slow. If you want results, you’ll have to wait.
This simple truth often escapes the global conversation about science and technology. Enthusiasm comes first, modesty and restraint come as an afterthought.
There has been an extended buzz in the news media about the use of transcranial “stimulation” techniques to enhance or impair math learning. Popular methods involve the application of a magnetic field or an electrical current to the surface of the skull, which can selectively disrupt (inhibit) or excite cells near the cortical surface.
Transcranial stimulation techniques
Model Transcranial Magnetic Stimulation setup. Electrons flow through the magnetic head coil (yellow) producing a perpendicularly aligned magnetic field (dashed maroon circles), which in turn induces an electrical field (dashed green circle) below the surface of the brain. Credit: Eric Wassermann, M.D., via Wikimedia Commons
Transcranial magnetic stimulation (TMS) is arguably the most popular technique as a magnetic field can be used to influence brain activity without directly affecting sensory or pain fibers present in the scalp. An electric current is first passed through a metal circuit or “head coil” placed above the head (see right). Current flow through the coil induces the generation of a perpendicular magnetic field which can penetrate into the brain. This magnetic field in turn, creates an electrical field in the same plane as the coil, but below the surface of the brain. Depending upon the parameters employed by researchers this technique can be used to produce a relatively targeted excitation or inhibition of the underlying region of cortex.
Norenzayan and Gervais top off recent work studying religious and non-religious belief by trying to address distinctions between the cognitive mechanisms that promote these disparate forms of thinking. This topic is of immediate interest, I think, given the rapid growth in people who claim to disbelieve religious claims–albeit amid a world predominantly filled with believers of one stripe or another. Also, in the United States, the issue of religious belief and the rights of those who believe in a particular faith has become a major feature of the “culture wars”. Continue reading →
I have been planning for quite some time to start a discussion around “physician-assisted suicide”, but it’s been difficult to really dig into this sensitive issue. At this point, I’ve decided to just dive right in and aim to address the sensitivity and appropriateness of this discussion as I move forward.
Credit: Tom Ellenberger, Washington University School of Medicine in St. Louis, via Wikimedia Commons
In some sense, just about everything we do in life is toxic. There is a probability that just by crossing the street I will be hit by a car. Physical exertion and exercise can precede the onset of a heart attack or stroke. Vegetables, meats and just about every food source on the planet can potentially contain copious amounts of carcinogens. Sunlight releases high levels of toxic rays that damage our cells. Frankly, I find world to be a pretty scary place. Continue reading →
For those who have read my rather stringent criticism of Thomas Insel at the National Institutes of Mental Health (NIMH), you will be happy to hear a more complimentary tone. As the American Psychiatric Association (APA) is putting the finishing touches on the controversial, fifth version of its Diagnostic and Statistical Manual (DSM-5), Insel has pointed to a recent initiative at NIMH to begin developing a biomarker-based classification scheme, regardless of DSM diagnosis.
Michael Gazzaniga recently stopped by UBC for the Quinn Memorial Lecture and I had a chance to listen in on his talk about free will, which I assume is taken from his most recent book on the topic. Past Quinn lectures are available on Youtube, so I imagine the Gazzaniga talk will uploaded at some time in the future.
In 2009, researchers from the University of British Columbia reported on a case of developmental topographical disorientation. The woman, referred to only as patient 1 (Pt1), is the first reported individual to demonstrate this profound and lifelong impairment in navigation. Throughout her school years, Pt1 was forced to follow her sisters or parents to school and friends to extracurricular activities. As an adult, she relies upon specific, stereotyped instructions to travel from work to home, using simple, unmistakable landmarks along the way. Any deviation from this course and Pt1 can no longer use her navigation abilities to rediscover this planned route.
A similar case is subject to a brief documentary presented by the New York Times:
New research suggests a novel form of deep brain stimulation (DBS) may be beneficial in treatment-resistant major depression (MDD). In a small, short-term pilot study, German researchers implanted electrodes into the medial forebrain bundles (MFBs) of 7 patients suffering from recurrent and/or long-lasting episodes of major depression which were non-responsive to medication, psychotherapy or electroconvulsive-shock therapy (ECT). This treatment-resistant sub-group of MDD patients likely represents a significant proportion of all sufferers (possibly as high as 1-in-4, according to the STAR*D study). Continue reading →
I’ve previously addressed the surprising finding that people with extensive damage to the brain’s “fear center” are capable of experiencing fear and how this can be explained, in part, by recognizing that features of human psychology do not exclusively rely upon individual brain structures. But, this leaves us with a dilemma: even if emotions like fear are encoded across many structures of the brain simultaneously, damage to some of these structures should still impair or eliminate these emotions. Indeed, if we consider the case of SM, she was capable of experiencing a state akin to fear or panic, but only in very specific circumstances: she couldn’t detect external threats, but internal threats (e.g. CO2-mediated suffocation) do appear to register. Perhaps then the amygdala is not a “fear center” so much as a threat or salience (“important stuff”) detector, which is commonly used to elicit fear responses to threatening stimuli.