How to Read Minds: THE FUTURIST Interviews Neuroscientist Jody Culham

Subject(s):

Your secret plans aren't so secret after all. Last year, using functional magnetic resonance imaging (fMRI), which reveals blood flow within the brain, Jody Culham and her fellow researchers at the University of Western Ontario discovered that areas of the brain associated with motion exhibit increased blood flow not only when acting but also when considering whether or not to act. In the January-February issue of THE FUTURIST magazine, we look into the study. Below Culham explains her work and its applications.

THE FUTURIST: You state:

“Given that conventional fMRI analyses in humans have shown widespread, highly overlapping, and essentially undifferentiated activations for different movements (Culham et al., 2006), combined with mounting evidence that standard fMRI methods may ignore the neural information contained in distributed activity patterns (Harrison and Tong, 2009), we expected that our pattern classification approach might offer a new understanding of how various parieto-frontal brain regions contribute to the planning of goal-directed hand actions.”

What do you mean by: “standard fMRI methods may ignore the neural information contained in distributed activity?” Did this experiment use non-standard fMRI methods?

Jody Culham: In functional MRI, we measure activation levels within "voxels" (= "volumetric pixels"), which are little cubes, typically about 3 mm x 3 mm x 3 mm. Until recently, the standard approach was to average activation across a whole bunch of adjacent voxels in a brain area to look at how the overall activation level changed. For example, if we measured the activation levels across an area involved in grasping, we might find similar level for grasping a teacup by the handle vs. by the bowl. In the past few years, decoding approaches ("multivoxel pattern analysis") have been developed to look at the pattern of activation across voxels within an area. For example, it may be that when handle-grasping, one particular voxel in the "grasping area" is strongly activated while another is strongly deactivated; whereas, when bowl-grasping, the pattern is reversed. In this case, even though the total activation across the whole area is the same, by using the patterns, we can guess better than chance which action a subject in the brain scanner performed.

THE FUTURIST: At the end of the paper, you hint at one possible application in prosthesis development, what other applications can you think of? Feel free to speculate wildly.

Jody Culham: Well, to speculate wildly, I suppose that all of this work on brain-computer interfaces (BCIs) in general could lead to cyborg kinds of things even in normal people (whereas prosthetics would be aimed at people with handicaps, like spinal cord injuries). There are developments using things like brain waves (electroencephalography, EEG) to move a cursor on a screen, but EEG is quite coarse (and can't target a specific brain area with any precision). Potentially BCIs, such as multi-electrode implants, could perhaps be employed in normal brains to control things (cursors, avatars). We see our work as a proof of concept that a large number of specific areas within the human brain contain information about intended actions that could be used to control devices. Obviously it's not feasible to use a $4M brain scanner to do this in a large number of people, but there are other technical developments that may be able to tap into brain activation non-invasively (e.g, fNIR) or invasively (electrode implants). All of this is highly speculative as there are a huge number of technical and ethical issues to address.

THE FUTURIST: Are you familiar at all with the work of Nicole Speer? In a study conducted at Washington University's Dynamic Cognition laboratory (published in the journal Psychological Science in 2009,) Speer and her colleagues used fMRI to examine hemoglobin flow when people read fiction and discovered that the "readers mentally simulate each new situation encountered in a narrative. Details about actions and sensation are captured from the text and integrated with personal knowledge about past experiences." The brain regions that are activated "closely mirror those involved when people perform or imagine or observe similar real-world activities." It may be a irrelevant but it seems (to an admitted novice in these things) that the neurological “priming” effect of reading fiction is a bit like the priming effect you observed in your study.

Jody Culham: I'm not familiar with her work. However, it is consistent with a growing scientific literature suggesting that much of our understanding of things is based on simulation. For example, I might learn to ski by watching you ski and using the same motor control networks in my brain. I may even understand the word "ski" by invoking related concepts, including motor programs.

This interview was conducted by FUTURIST magazine deputy editor Patrick Tucker. Read the article on Culham's work here. Purchase the study here.