Neuroethics & Law Blog

Priming Effects in the New York Times

There is an article on "priming effects" in the science section of today's New York Times.  The article reviews some of the experiments which show how subconscious stimuli can affect our conscious choices.  For example:

In one 2004 experiment, psychologists led by Aaron Kay, then at Stanford University and now at the University of Waterloo, had students take part in a one-on-one investment game with another, unseen player.

Half the students played while sitting at a large table, at the other end of which was a briefcase and a black leather portfolio. These students were far stingier with their money than the others, who played in an identical room, but with a backpack on the table instead.

The mere presence of the briefcase, noticed but not consciously registered, generated business-related associations and expectations, the authors argue, leading the brain to run the most appropriate goal program: compete. The students had no sense of whether they had acted selfishly or generously.

In another experiment, published in 2005, Dutch psychologists had undergraduates sit in a cubicle and fill out a questionnaire. Hidden in the room was a bucket of water with a splash of citrus-scented cleaning fluid, giving off a faint odor. After completing the questionnaire, the young men and women had a snack, a crumbly biscuit provided by laboratory staff members.

The researchers covertly filmed the snack time and found that these students cleared away crumbs three times more often than a comparison group, who had taken the same questionnaire in a room with no cleaning scent. “That is a very big effect, and they really had no idea they were doing it,” said Henk Aarts, a psychologist at Utrecht University and the senior author of the study.

The article also discusses some related neuroscience research:

The brain appears to use the very same neural circuits to execute an unconscious act as it does a conscious one. In a study that appeared in the journal Science in May, a team of English and French neuroscientists performed brain imaging on 18 men and women who were playing a computer game for money. The players held a handgrip and were told that the tighter they squeezed when an image of money flashed on the screen, the more of the loot they could keep.

As expected, the players squeezed harder when the image of a British pound flashed by than when the image of a penny did — regardless of whether they consciously perceived the pictures, many of which flew by subliminally. But the circuits activated in their brains were similar as well: an area called the ventral pallidum was particularly active whenever the participants responded.

The article ends with the following somewhat controversial perspective:

Yet the new research on priming makes it clear that we are not alone in our own consciousness. We have company, an invisible partner who has strong reactions about the world that don’t always agree with our own, but whose instincts, these studies clearly show, are at least as likely to be helpful, and attentive to others, as they are to be disruptive.

Sociable Robots

The NYT Magazine cover story this week is about sociable robots, like Kismet, the fellow below.  Author Robin Marantz Henig seems impressed by the performances of a number of robots, until she learns that what looks like a robot developing "theory of mind" or self-awareness actually falls rather short.  However, while we can get a particular robot to perform a particular often unimpressive task, if we could get a single robot to do all of those tasks, we'd all likely be quite a bit more impressed.  Interestingly, some of the article's more impressive observations concern what we have learned about humans based on our interactions with robots rather than the other way around.

(Photo by Stephen Lewis for the NYT)

Here's one somewhat depressing vignette from the article:

Sherry Turkle, a professor in the Program in Science, Technology and Society at M.I.T., worries that sociable robots might be easier to deal with than people are and that one day we might actually prefer our relationships with our machines. A female graduate student once approached her after a lecture, Turkle said, and announced that she would gladly trade in her boyfriend for a sophisticated humanoid robot as long as the robot could produce what the student called “caring behavior.” “I need the feeling of civility in the house,” she told Turkle. “If the robot could provide a civil environment, I would be happy to help produce the illusion that there is somebody really with me.” What she was looking for, the student said, was a “no-risk relationship” that would stave off loneliness; a responsive robot, even if it was just exhibiting scripted behavior, seemed better to her than an unresponsive boyfriend.

The encounter horrified Turkle, who thought it revealed how dangerous, and how seductive, sociable robots could be. “They push our Darwinian buttons,” she told me. Sociable robots are programmed to exhibit the kind of behavior we have come to associate with sentience and empathy, she said, which leads us to think of them as creatures with intentions, emotions and autonomy: “You see a robot like that as a creature; you feel a desire to nurture it. And with this desire comes the fantasy of reciprocation. You begin to care for these creatures and to want the creatures to care about you.”

Ethics, Neuroimaging, and Limited States of Consciousness: workshop report (Murphy)

On June 28th, a group of neuroimagers, lawyers, clinicians, and ethicists gathered at Stanford to discuss issues surrounding research and care of patients in minimally conscious and persistent vegetative states.  The proceedings of the meeting will be published as a special issue of AJOB-Neuroscience in 2008, but here are some highlights:

The morning public session was kicked off by a plenary lecture by Albert Jonsen (professor emeritus at U of Washington).  Dr. Jonsen gave the audience a historical perspective on the ethics of neuroscience in his talk "Public policy and imaging: Historical considerations."  Joseph Fins (Cornell) was the first keynote speaker with his talk titled "Neuroethics and neuroimaging: Moving towards transparency," outlining how the research community should seek to achieve transparency about how neuroimaging could and should be used in clinical settings.  He recommended a pragmatist's approach, is wary of measuring consciousness and "transcendent truth," and offered specific suggestions such as moving beyond imaging snapshots to movies of clinical assessment, as well as linking imaging studies of patients with larger epidemiological studies enabled by a registry of patients.  His talk was commented on by Martha Farah (UPenn), Steven Laureys (Liege, Belgium), and William Winslade (UT).  The second keynote lecture was given by David Magnus (Stanford), titled "Clinical Ethics and PVS."  Dr. Magnus outlined seminal clinical ethics of cases of PVS patients and the legal and societal impact, and argued that PVS as a diagnostic category "may not stand up scientifically to do the ethical work it is being relied on to do" (paraphrase).  His talk was commented on by James Bernat (Dartmouth), Joy Hirsch (Cornell), and Stephen Morse (UPenn).  Audio recordings of these talks and panel discussions will be available at neuroethics.stanford.edu next week (I'll announce here when they're posted).

The afternoon sessions were three working groups of 7-8 of each of the invited participants, including community stakeholders.  These working groups were: Consent, Experimental Protocols, and Clinical Objectives.  In these groups, participants aimed to clearly identify the current ethical issues and critical open questions in conducting research and providing care to patients in MCS/PVS states and the responsibilities to patient's families, the media, IRB and grant-making bodies, and the public.  The results of each working group were reported to the general group at the end of the day, and will be published as a target article in the forthcoming AJOB-Neuroscience special issue. 

The invited participants were extremely engaged in the discussions surrounding this important and poorly understood state of human existence.  The conference organizers (Judy Illes and Joseph Fins) felt that new ground had been broken in identifying ethical issues and developing ways to offer guidance to the research and clinical communities.   Look for the AJOB-Neuroscience special issue for a full report and open peer commentaries!

Free Online Neuropsychopharmacology Textbook

The American College of Neuropsychopharmacology has just put a huge textbook online with free access.  With 134 chapters, this is sure to be a helpful resource. (HT: MindHacks)

FDA Approves Dementia Patch

The drug is already available, but delivery through a patch reduces g.i. side effects. Story here.

MacIntyre on Easing Painful Memories

In "I Won't Give Memory a Nip and Tuck," Times of London columnist Ben MacIntyre expresses his skepticism over the merits of drugs designed to dampen or erase traumatic memories.  He's not skeptical of the scientific prospects of the drugs (which would surely be a legitimate stance).  Rather, he's skeptical of their merits for improving our lives.  In a few paragraphs, he summarizes a number of the points made in in 2003 by the President's Council on Bioethics, writing on the same subject.  Here's an excerpt:

We could become, in effect, the curators of our own memory-libraries, chucking out or sealing up the volumes that distress us, leaving only shelf upon shelf of happy reminiscences.

. . .

Some ravaged lives will surely be improved by easing painful memories, but most would be diminished. As anyone knows who has observed the slow, cruel larceny of Alzheimer’s disease, the erosion of the sad memories is just as tragic as the elimination of the joyful ones.

(Hat tip: Frank Pasquale)

Dampening Memories from the Distant Past

I have written before about the possible use of propranolol to dampen traumatic memories (see here).  The initial studies tested the effects of propranolol on memories of recent events (i.e., it was thought that propranolol had to be taken within about six hours of the traumatic event in order to ease the emotional sting of a memory.)  The jury is still out whether propranolol indeed has such effects.

Meanwhile, researchers are already testing whether propranolol can affect the quality of memories from the more distant past.  For example, can a subject take propranolol while recalling traumatic memories from many years ago, in hopes that the memories will reconsolidate with less emotional valence?  A recent small study by Brunet et al. suggests that it might.  So far, I've only seen the following abstract:

The beta-adrenergic blocker propranolol given within hours of a psychologically traumatic event reduces physiologic responses during subsequent mental imagery of the event. Here we tested the effect of propranolol given after the retrieval of memories of past traumatic events. Subjects with chronic post-traumatic stress disorder described their traumatic event during a script preparation session and then received a one-day dose of propranolol (n=9) or placebo (n=10), randomized and double-blind. A week later, they engaged in script-driven mental imagery of their traumatic event while heart rate, skin conductance, and left corrugator electromyogram were measured. Physiologic responses were significantly smaller in the subjects who had received post-reactivation propranolol a week earlier. Propranolol given after reactivation of the memory of a past traumatic event reduces physiologic responding during subsequent mental imagery of the event in a similar manner to propranolol given shortly after the occurrence of a traumatic event.

Here's the optimistic take on this research from BBC news:

The researchers treated 19 crash or rape victims for 10 days with a drug, or a placebo.

The volunteers were asked to recall their memories of a traumatic event that had happened 10 years earlier.

A week later the researchers found that those people who were given a shot of propranolol showed fewer signs of stress, such as raised heart rate, when recalling their trauma.

The researchers believe that memories are initially stored in the brain in a malleable, fluid state before becoming hard-wired into the circuitry.

Then, when they are recalled, they once again become fluid - and capable of being altered.

They believe propranolol disrupts the biochemical pathways that allow a memory to "harden" after it has been recalled.

(Hat tip: Mind Hacks)