The future of fMRI

Nature has an article looking at the future of fMRI brain scanning in light of its long-lasting hype and recently discovered problems.

Brain scanning has become massively popular both in the scientific community and in the media, in great part because the pictures it produces seem quite intuitive: images of the brain with colours on it which apparently represent neural activity when we’re doing something.

However, the current situation with fMRI is nicely but inadvertantly captured in the article:

It has turned psychology “into a biological science”, says Richard Frackowiak…

[two sentences later]

Perhaps the biggest conundrum in fMRI is what, exactly, the technique is measuring.

fMRI has indeed turned much of psychology into a biological science but it hasn’t really given us a fundamentally deeper understanding of neuropsychology largely due to the measurement problem.

Recent revelations that fMRI studies are not as reliable as we thought and that some common ways of analysing data may be flawed have made many people question the utility of the technique – or at least, many of the past studies that may not have been well controlled.

The Nature article looks at where the science will go next, although I can’t help thinking that if it became less expensive the gloss would rub off – and then at least we could assess it a little more reasonably.

Sadly, scientists are no less attracted to bling.
 

Link to Nature article ‘Brain imaging: fMRI 2.0′

3 Comments

  1. Posted April 4, 2012 at 5:34 pm | Permalink

    From Ginger Campbell’s Interview with Dr. Jaak Panksepp, Author of Affective Neuroscience: The Foundations of Human and Animal Emotions

    “In order to understand the mind—especially the emotional mind, there’s no alternative but to take an evolutionary perspective. The only organ we have in the body that is clearly evolutionarily layered is the brain.”

    “My feeling is that the social brain has many levels. If you don’t understand the foundational level, then you can do brain imaging until you’re blue in the face, but you still will not understand the process at a deep causal level.”
    —————
    For me, it is not so much the need to understand cause and effect as it is to stop psychologists from proposing that their work establishes it. Visual appeal is a function of chemically activated ligand-receptor binding, for example. Each time I read that brain imagery has established a link between facial or other appealing physical characteristics and behavior, I want to ask the authors: Is there am animal model for that? But I know what the answer must be. Olfactory/pheromonal input establishes visual appeal in every other species, so pictures of brain activity are like pictures of other people or pictures of food, and pictures do not directly link cause and effect to brain-based behavior. Pictures link associations and conditioned responses to the chemistry of behavior.

  2. Rich Morris
    Posted April 8, 2012 at 12:21 am | Permalink

    J V Kohl appears to be saying psychology can’t establish cause-and-effect because all psychology is really chemistry (of behaviour). But I think this makes as big mistake as neuroscientists thinking they have explained psychology because they can point to a brain region. This mistake is the same error as phrenology.

    There are different levels of explanation, and one level (e.g. chemistry) may not map in a one-to-one fashion to the next level (e.g. behaviour). In particular, when trying to explain some examples of behaviour such as memory, learning, or attention, it does no good to know which chemicals or brain regions were involved. Instead, what is needed is needed is a model in psychological terms (e.g. Rescorla-Wagner model). Psychological models can be instantiated in different ways, in different brain regions, with different chemical events. But they predict and explain behaviour because they are the appropriate level of explanation. Until neuroscientists (and chemists?) appreciate they are dealing with psychological terms, their “explanations” of behaviour will be neuvo-phrenology.

    • Posted April 8, 2012 at 5:03 pm | Permalink

      Thanks, Rich. My explanation of behavior includes all levels: gene, cell, tissue, organ, organ system. It begins with the epigenetic effects of nutrient chemicals on intracellular signaling in bacteria and follows nutrient metabolism to pheromone production across species to include the same molecular mechanisms in the honeybee model, extended to humans. The fact that many species do not have brains does not limit the applicability of the levels of biological organization in my model, since it is factually based in what is now known about molecular biology across species from microbes to man. See, for example Kohl, J.V. (2012) Human pheromones and food odors: epigenetic influences on the socioaffective nature of evolved behaviors. Socioaffective Neuroscience & Psychology, 2: 17338. DOI: 10.3402/snp.v2i0.17338


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