Showing posts with label MRI. Show all posts
Showing posts with label MRI. Show all posts

Sunday, October 20, 2013

Alva Noë - MRI Scans Can't Show Us Consciousness or Personhood (Dogs Are People, Too)

In his recent column for NPR's 13.7 Cosmos and Culture, philosopher Alva Noë argues in favor of animal intelligence and consciousness - that we don't see the dog's consciousness or personhood when you look at its brain in MRI scans. Their subjective states are best experienced when we spend time with them, not as scientists or observers but as companions.

So first up is the New York Times column by Gregory Berns that inspired Noë's column, and then Noë's column from NPR.

Dogs Are People, Too

By GREGORY BERNS
Published: October 5, 2013 


Jane Evelyn Atwood/Contact Press Images 

FOR the past two years, my colleagues and I have been training dogs to go in an M.R.I. scanner — completely awake and unrestrained. Our goal has been to determine how dogs’ brains work and, even more important, what they think of us humans.
Multimedia
Video: How Dogs Love Us (YouTube)
Now, after training and scanning a dozen dogs, my one inescapable conclusion is this: dogs are people, too.

Because dogs can’t speak, scientists have relied on behavioral observations to infer what dogs are thinking. It is a tricky business. You can’t ask a dog why he does something. And you certainly can’t ask him how he feels. The prospect of ferreting out animal emotions scares many scientists. After all, animal research is big business. It has been easy to sidestep the difficult questions about animal sentience and emotions because they have been unanswerable.

Until now.

By looking directly at their brains and bypassing the constraints of behaviorism, M.R.I.’s can tell us about dogs’ internal states. M.R.I.’s are conducted in loud, confined spaces. People don’t like them, and you have to hold absolutely still during the procedure. Conventional veterinary practice says you have to anesthetize animals so they don’t move during a scan. But you can’t study brain function in an anesthetized animal. At least not anything interesting like perception or emotion.

From the beginning, we treated the dogs as persons. We had a consent form, which was modeled after a child’s consent form but signed by the dog’s owner. We emphasized that participation was voluntary, and that the dog had the right to quit the study. We used only positive training methods. No sedation. No restraints. If the dogs didn’t want to be in the M.R.I. scanner, they could leave. Same as any human volunteer.

My dog Callie was the first. Rescued from a shelter, Callie was a skinny black terrier mix, what is called a feist in the southern Appalachians, from where she came. True to her roots, she preferred hunting squirrels and rabbits in the backyard to curling up in my lap. She had a natural inquisitiveness, which probably landed her in the shelter in the first place, but also made training a breeze.

With the help of my friend Mark Spivak, a dog trainer, we started teaching Callie to go into an M.R.I. simulator that I built in my living room. She learned to walk up steps into a tube, place her head in a custom-fitted chin rest, and hold rock-still for periods of up to 30 seconds. Oh, and she had to learn to wear earmuffs to protect her sensitive hearing from the 95 decibels of noise the scanner makes.

After months of training and some trial-and-error at the real M.R.I. scanner, we were rewarded with the first maps of brain activity. For our first tests, we measured Callie’s brain response to two hand signals in the scanner. In later experiments, not yet published, we determined which parts of her brain distinguished the scents of familiar and unfamiliar dogs and humans.

Soon, the local dog community learned of our quest to determine what dogs are thinking. Within a year, we had assembled a team of a dozen dogs who were all “M.R.I.-certified.”

Although we are just beginning to answer basic questions about the canine brain, we cannot ignore the striking similarity between dogs and humans in both the structure and function of a key brain region: the caudate nucleus.

Rich in dopamine receptors, the caudate sits between the brainstem and the cortex. In humans, the caudate plays a key role in the anticipation of things we enjoy, like food, love and money. But can we flip this association around and infer what a person is thinking just by measuring caudate activity? Because of the overwhelming complexity of how different parts of the brain are connected to one another, it is not usually possible to pin a single cognitive function or emotion to a single brain region.

But the caudate may be an exception. Specific parts of the caudate stand out for their consistent activation to many things that humans enjoy. Caudate activation is so consistent that under the right circumstances, it can predict our preferences for food, music and even beauty.

In dogs, we found that activity in the caudate increased in response to hand signals indicating food. The caudate also activated to the smells of familiar humans. And in preliminary tests, it activated to the return of an owner who had momentarily stepped out of view. Do these findings prove that dogs love us? Not quite. But many of the same things that activate the human caudate, which are associated with positive emotions, also activate the dog caudate. Neuroscientists call this a functional homology, and it may be an indication of canine emotions.

The ability to experience positive emotions, like love and attachment, would mean that dogs have a level of sentience comparable to that of a human child. And this ability suggests a rethinking of how we treat dogs.

DOGS have long been considered property. Though the Animal Welfare Act of 1966 and state laws raised the bar for the treatment of animals, they solidified the view that animals are things — objects that can be disposed of as long as reasonable care is taken to minimize their suffering.

But now, by using the M.R.I. to push away the limitations of behaviorism, we can no longer hide from the evidence. Dogs, and probably many other animals (especially our closest primate relatives), seem to have emotions just like us. And this means we must reconsider their treatment as property.

One alternative is a sort of limited personhood for animals that show neurobiological evidence of positive emotions. Many rescue groups already use the label of “guardian” to describe human caregivers, binding the human to his ward with an implicit responsibility to care for her. Failure to act as a good guardian runs the risk of having the dog placed elsewhere. But there are no laws that cover animals as wards, so the patchwork of rescue groups that operate under a guardianship model have little legal foundation to protect the animals’ interest.

If we went a step further and granted dogs rights of personhood, they would be afforded additional protection against exploitation. Puppy mills, laboratory dogs and dog racing would be banned for violating the basic right of self-determination of a person.

I suspect that society is many years away from considering dogs as persons. However, recent rulings by the Supreme Court have included neuroscientific findings that open the door to such a possibility. In two cases, the court ruled that juvenile offenders could not be sentenced to life imprisonment without the possibility of parole. As part of the rulings, the court cited brain-imaging evidence that the human brain was not mature in adolescence. Although this case has nothing to do with dog sentience, the justices opened the door for neuroscience in the courtroom.

Perhaps someday we may see a case arguing for a dog’s rights based on brain-imaging findings.


~ Gregory Berns is a professor of neuroeconomics at Emory University and the author of How Dogs Love Us: A Neuroscientist and His Adopted Dog Decode the Canine Brain.
* * * * *

If You Have To Ask, You'll Never Know


by Alva Noë
October 11, 2013


If you need empirical information about what is happening in the brain of a dog to know that dogs think, then either you've never met a dog or your own humanity is in doubt.
Sometimes it is our questions that get in the way.

Suppose two ships are sinking and you can save only one. How should you decide which ship to save? Should you save the one with the most people in it?

When this question was put by her teacher to Sissy Jupe, a young character in Charles Dickens' Hard Times, she could only weep and run away. She was unable to to take up the standpoint from which this could even be asked. For Sissy, the very question was repugnant, perhaps because it presupposed that the value of a person is the sort of thing that can be chalked up, counted and weighed. Her caring, her engagement with others, precluded that sort of calculating detachment.

I had to think of Sissy Jupe when I read Gregory Berns' essay in The New York Times about his research on the dog brain and his startling (to some) conclusion that dogs are people, too.

If you need information about what is happening in the brain of a dog to know that dogs think and have feelings and emotions, then either you've never met a dog or your own humanity is in doubt.

You can no more seriously entertain the possibility that a dog is a mere automaton than you can entertain such a hypothesis about your human loved ones. To do so would require you to stand back and look at what a dog (or a person) does (and says) as devoid of meaning and expressive power. And to do that would be disrespectful. This is the Sissy Jupe point.

It is certainly true that no amount of information about the movements and behaviors (including linguistic behaviors) of animals, human or otherwise, can suffice to establish, beyond any possible doubt, that they think and feel and have emotions, that they are conscious.

So, I ask, can it be seriously maintained that information about brain activity can settle such skeptical worries decisively? How do we know that what happens in me when my brain fires neurons is the same as what happens in you? How could we ever know that for sure?

Should prospective husbands and wives do due diligence and check MRIs before tying the knot, just to make sure they are both really people?

My own suggestion — I develop this in Out of Our Heads — is that we should not think of our appreciation of the consciousness of people (and dogs) as the sort of thing we discover on the basis of empirical investigation of their brains or their behavior. It is, rather, a presupposition of the kinds of lives we lead together.

You could not love someone (dog, or person), if you took seriously the possibility that he or she (or it) might, appearances to the contrary, turn out to be a robot. And, as the writer and professional animal trainer Vicky Hearne has argued persuasively, you can't actually work with dogs if you don't take them seriously as, well, responsible agents. A search-and-rescue dog, for example, or a seeing-eye dog, is a collaborator, not a tool.

Berns writes in his piece:
"By looking directly at their brains and bypassing the constraints of behaviorism, M.R.I.'s can tell us about dogs' internal states."
Yes, indeed. I'm all for studying dog brains and for using such studies to inform our understanding of dog psychology. But you don't see the dog's consciousness or personhood when you look at its brain. Those internal states come into focus only when we appreciate, with Sissy Jupe, that we are not detached observers, not even when we are scientists.


~ You can keep up with more of what Alva Noë is thinking on Facebook and on Twitter: @alvanoe

Thursday, August 22, 2013

'No Such Thing' as Left- or Right-Brained People - An Evaluation of the Left-Brain vs. Right-Brain Hypothesis with Resting State Functional Connectivity Magnetic Resonance Imaging


A while back I posted some information on the supposed right-brain/left-brain dominance of how one sees a spinning dancer (above). Now there is new evidence that suggests there is not any real right- or left-brain people or personality types.

Main points:
Dr. Jeff Anderson, lead author of the study, explains:
"It is absolutely true that some brain functions occur in one or the other side of the brain. Language tends to be on the left, attention more on the right.  
But people don't tend to have a stronger left- or right-sided brain network. It seems to be determined more, connection by connection."
Jared Nielsen, a graduate student in neuroscience at the University of Utah and one of the study authors, adds:
"If you have a connection that is strongly left-lateralized, it relates to other strongly lateralized connection only if both sets of connections have a brain region in common."
Interesting. Here is the summary from Medical News Today - below that is the abstract and citation for the original article (it's Open Access).

'No such thing' as left or right brained people


Written by Honor Whiteman | Medical News Today
19 Aug 2013

We have all heard references to people being a "left-brained" or "right-brained" thinker. But researchers from the University of Utah say their latest research shows this is a myth.

Previous studies over the years have suggested that we use one half of our brain more often than the other, playing a part in the type of personality we have.
 
While the left side of the brain is usually associated with logical, analytical and detail-oriented behavior, the right side has been connected to creative, thoughtful and subjective thinking.

But a new study published in the journal PLOS ONE, suggests there is no evidence within brain imaging that proves some people are right-brained or left-brained.

The research team conducted a two-year study of 1,011 people who were part of the International Neuroimaging Data-Sharing Initiative (INDI), and who were between the ages of 7 and 29.

All participants had the functional lateralization of their brains measured. Functional lateralization means there are specific mental processes that take place in either the brain's left or right hemisphere.


Researchers have said the theory of "left-brained" or "right-brained" thinkers is nothing more than a myth

The scientists conducted the brain measurements using magnetic resonance imaging (MRI) analysis, which involved the participants lying in the scanner for 5 to 10 minutes while their "resting" brain measurements were taken. This allowed the researchers to correlate brain activity in one area of the brain and compare it with another.

The researchers then divided the brain into 7,000 regions and analyzed which regions of the brain showed more functional lateralization.

All connections in the brain were examined, and all possible combinations of the brain regions were correlated for each brain region that was left-lateralized or right-lateralized.

The results of the scan showed patterns indicating that a brain connection may be strongly left or right-lateralized. But they found no relationship that individuals "preferentially" used their left-brain network or right-brain more often.

Dr. Jeff Anderson, lead author of the study, explains:
"It is absolutely true that some brain functions occur in one or the other side of the brain. Language tends to be on the left, attention more on the right. 
But people don't tend to have a stronger left- or right-sided brain network. It seems to be determined more, connection by connection."
Jared Nielsen, a graduate student in neuroscience at the University of Utah and one of the study authors, adds:
"If you have a connection that is strongly left-lateralized, it relates to other strongly lateralized connection only if both sets of connections have a brain region in common."
Results of this study are groundbreaking, Nielsen says, as they may change the way people think about the "right-brain versus left-brain theory."

"Everyone should understand the personality types associated with the terminology 'left-brained' and 'right-brained' and how they relate to him or her personally," he says.

"However, we just do not see patterns where the whole left-brain network is more connected or the whole right-brain network is more connected in some people. It may be that personality types have nothing to do with one hemisphere being more active, stronger, or more connected."

Here is the abstract for the full article, available for free as an Open Access post at PLoS ONE:

Figure 5 Significant correlation of lateralized connections across subjects.

Figure 5. Significant correlation of lateralized connections across subjects.

An Evaluation of the Left-Brain vs. Right-Brain Hypothesis with Resting State Functional Connectivity Magnetic Resonance Imaging



Jared A. Nielsen, Brandon A. Zielinski, Michael A. Ferguson, Janet E. Lainhart, Jeffrey S. Anderson

Abstract

Lateralized brain regions subserve functions such as language and visuospatial processing. It has been conjectured that individuals may be left-brain dominant or right-brain dominant based on personality and cognitive style, but neuroimaging data has not provided clear evidence whether such phenotypic differences in the strength of left-dominant or right-dominant networks exist. We evaluated whether strongly lateralized connections covaried within the same individuals. Data were analyzed from publicly available resting state scans for 1011 individuals between the ages of 7 and 29. For each subject, functional lateralization was measured for each pair of 7266 regions covering the gray matter at 5-mm resolution as a difference in correlation before and after inverting images across the midsagittal plane. The difference in gray matter density between homotopic coordinates was used as a regressor to reduce the effect of structural asymmetries on functional lateralization. Nine left- and 11 right-lateralized hubs were identified as peaks in the degree map from the graph of significantly lateralized connections. The left-lateralized hubs included regions from the default mode network (medial prefrontal cortex, posterior cingulate cortex, and temporoparietal junction) and language regions (e.g., Broca Area and Wernicke Area), whereas the right-lateralized hubs included regions from the attention control network (e.g., lateral intraparietal sulcus, anterior insula, area MT, and frontal eye fields). Left- and right-lateralized hubs formed two separable networks of mutually lateralized regions. Connections involving only left- or only right-lateralized hubs showed positive correlation across subjects, but only for connections sharing a node. Lateralization of brain connections appears to be a local rather than global property of brain networks, and our data are not consistent with a whole-brain phenotype of greater “left-brained” or greater “right-brained” network strength across individuals. Small increases in lateralization with age were seen, but no differences in gender were observed.

Full Citation
Nielsen JA, Zielinski BA, Ferguson MA, Lainhart JE, Anderson JS. (2013, Aug 14). An Evaluation of the Left-Brain vs. Right-Brain Hypothesis with Resting State Functional Connectivity Magnetic Resonance Imaging. PLoS ONE, 8(8): e71275. doi: 10.1371/journal.pone.0071275