Dr Caroline Leaf – Better graphics, same content

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In the world of marketing, visual media is king. Humans are sight based creatures. About thirty percent of our brains cortex is dedicated to vision , compared to 8 percent for touch and 2 percent for hearing http://channel.nationalgeographic.com/brain-games/articles/brain-games-watch-this-perception-facts/)

It’s no wonder then that sites like Pinterest and Instagram have so rapidly become such dominant sites on the social media landscape. And why billions of dollars are invested in visual advertising on TV and billboards.

Dr Caroline Leaf is a communication pathologist and self titled cognitive neuroscientist. In the last few weeks, she’s gone for a new look for her Instagram and Facebook posts – gone are the simple lines, plain text and stand alone logo. Her posts have gone glam, with backgrounds of her photo treated with coloured layering and shading, overlaid with Dr Leafs favourite text. Sometimes the text is pretty easy to read. Other times it looks like a 4th grade class got to take turns picking the font and text size for each different word. But hey, it’s edgy, it’s happening, it’s so hot right now.

It’s a real shame that she only chose to update the look and not the actual content of her social media memes. Take today’s offering as an example: “The mind processes. The brain reflects this processing.” (The unsaid conclusion being that, “The mind controls the brain.”)

I’ve written about this meme a few times (here, here, here and here, as a small sample). But let’s relook at it again, since Dr Leaf is unwilling to reconsider the statements lack of validity.

Does the mind really control the brain, or does the brain control the mind? Well, if the mind was separate from the brain and controlled the brain, then the mind would be able to function independently of the brain. And also, if the mind was separate to the brain, then changes to the brain would not influence the function of the mind.

It’s difficult to show that a person has a mind without a brain. You can’t really remove someone’s brain and then put it back again, so not many people are keen to volunteer for that study. But anecdotally, have you ever heard of a person who has woken from a coma having spend all that time in deep thought?

What IS much easier to study, and has been proven over the course of centuries, is the change to our cognitive function when our brain is changed, physically or functionally.

The mind changes when the function of the brain is changed by medications.
The mind changes when the function of the brain is changed by illicit drugs.
The mind changes when the function of the brain is changed by electrical stimulation.
The mind changes then the structure of the brain is changed by tumours or injuries.

In 1848, a man named Phineas Gage was packing gunpowder in some rock when an accidental detonation blasted a foot-long iron rod through the left face and forehead, severely damaging the left frontal lobe of his brain. History records that his personality changed from polite, well mannered, and well spoken to fitful, irreverent, impatient of restraint or advice, obstinate and capricious [1].

Whilst Phineas Gage was is most famous, other brain injuries can also change the way in which someone thinks. For example, lesions of the parietal lobe of the brain changes the way people see their own bodies. Baars writes, “Patients suffering from right parietal neglect can have disturbing alien experiences of their own bodies, especially of the left arm and leg. Such patients sometimes believe that their left leg belongs to someone else (often a relative), and can desperately try to throw it out of bed. Thus, parietal regions seem to shape contextually both the experience of the visual world and of one’s own body.” [2]

Some might argue that the mechanism of injury might be the variable that could change someone’s personality. After all, if an iron rod was blasted through my skull, I might be a little antsy too. But other structural change to the brain, not associated with a sudden traumatic event, can also result in personality changes – it’s well recognised that personality changes can be the first presenting symptom of brain tumours, for example.

Though the brain doesn’t have to be horribly distorted for the mind to change. In the last couple of decades, a tool has been developed called TMS – short for transcranial magnetic stimulation. A magnetic pulse is delivered over a part of the skull, passing through the bone to reach the brain, causing changes to the electrical current running through the nerve cells. Stimulation of different intensities can either turn off the nerve cells or excite them. TMS has become a great tool for studying cognitive neuroscience because it directly changes the function of the brain in a well localised and temporary manner. It’s also easy for scientists to blind the subjects to whether they’re receiving the treatment or a sham treatment, so the results are reliable. Research shows that when the frontal lobes of the brain are changed by the electrical signals, their executive function also changes [3].

Changes to the function of the brain are known to change the function of the mind and have been known to do so for centuries. From religious hallucinogens to Woodstock hippies, drugs of various forms have been used to alter mood, thought, and perceptions of reality. But there’s a drug that’s much more common, that’s known for its ability to alter our brains thinking ability the world over, and even Dr Leaf enjoys it.

Like most people, my morning doesn’t really start until after my first cup of coffee. Sure, I’m functional, but barely. Fifteen minutes after the first short black is in my system, I find that I’m much more alert and my thinking is clearer.

What’s changed? Is it my mind changing the function of my brain, or is it the coffee, specifically the caffeine in it, that’s changing my brain which is in turn is making my mind clearer and sharper? I think the answer is obvious. Caffeine is the most commonly used recreational drug in the history of mankind, and every cup of java (real coffee that is, not the travesty that is decaf) is more proof against Dr Leaf’s dogmatic misrepresentation of basic science.

So, if the mind is changed by alterations to the structure and/or function of our physical brain, it follows that our mind must be a function of our brain. Therefore, the mind does not process, while the brain simply hangs on for the ride. Rather, the brain processes, and our mind reflects this processing.

Dr Leaf can tart up her memes all she likes, but until she changes the content of her memes to match some actual science, it’s all just smoke and mirrors. The truth doesn’t need visual pimping. It is simply the truth.


[1]        Fumagalli M, Priori A. Functional and clinical neuroanatomy of morality. Brain : a journal of neurology 2012 Jul;135(Pt 7):2006-21.
[2]        Baars BJ. Global workspace theory of consciousness: toward a cognitive neuroscience of human experience. Progress in brain research 2005;150:45-53.
[3]        Guse B, Falkai P, Wobrock T. Cognitive effects of high-frequency repetitive transcranial magnetic stimulation: a systematic review. J Neural Transm 2010 Jan;117(1):105-22.

Dr Caroline Leaf and the Myth of the Blameless Brain

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When I came back to Facebook this morning, I found this from Dr Leaf on my feed,

“Don’t blame your physical brain for your decisions and actions. You control your brain!”

Dr Caroline Leaf is a Communication Pathologist and a self-titled Cognitive Neuroscientist. Her post follows her theme of the last couple of weeks, the premise that the mind is the dominant cognitive force, controlling the physical brain, and indeed, all matter. I have written about the Myth of Mind Domination in a previous blog. But Dr Leaf’s latest offering here deserves special attention.

Lets think about her statement in more detail:

“Don’t blame your physical brain for your decisions and actions.”

What Dr Leaf is really saying is that the physical brain has no role in your choices or behaviour whatsoever, because if your physical brain had a role in the decisions and actions you make, it would also carry some blame for your poor decisions and actions.

“You control your brain.”

The question to ask here is, “Which part of ‘you’ controls your brain?” Her answer would be, “Your mind”, although she never says where the mind is. Certainly not in the physical brain or even in our physical body, since “Our mind is designed to control the body, of which the brain is a part, not the other way around.” [1: p33].

So an ethereal, disembodied force is in full control of our physical body, such that our brain has no role in the decisions we make or actions we take. Even at this stage of analysis, Dr Leaf’s statement is ludicrous. But wait, there’s more.

Dr Leaf’s statement puts her at odds with real Cognitive Neuroscientists. Professor Patrick Haggard is the Deputy Director of the Institute of Cognitive Neuroscience at the University College London. He has authored or co-authored over 350 peer-reviewed articles on the neuroscience of making choices. He writes, “Modern neuroscience rejects the traditional dualist view of volition as a causal chain from the conscious mind or ‘soul’ to the brain and body. Rather, volition involves brain networks making a series of complex, open decisions between alternative actions.” [2] Strike one for Dr Leaf.

Dr Leaf’s statement puts her at odds with herself. Two weeks ago when misinterpreting James 1:21, Dr Leaf wrote, “How you react to events and circumstances of your life is based upon your perceptions.” Perception is classically defined in neurobiology as conscious sensory experience [3: p8] although the work of cognitive neuroscientists has shown that perception can also be non-conscious [4, 5]. Either way, perception is based entirely on processing within the brain [3: p6-11]. So one week, Dr Leaf is saying that our brain determines how we behave, and then ten days later, she is telling us that our brain does not determine how we behave. Which is it? Strike two for Dr Leaf.

Finally, Dr Leaf’s statement is borderline insulting to the sufferers of congenital or acquired brain disorders. Would you tell a stroke patient that they shouldn’t blame their physical brain for their immobility, because they’re mind is in control of their brain? What about a child with Cerebral Palsy? Would you tell a mother of a child with Downs Syndrome that their child is having recurrent seizures because they aren’t using their mind properly to control their brain? Dr Leaf is doing exactly that. I find it incredible that she could be so insensitive, given her background as a speech pathologist working with patients with Acquired Brain Injury.

I imagine that her defence would be something along the lines of, “What I meant was, ‘don’t blame your normal physical brain for your decisions and actions. You control your functional brain.’” That sort of explanation would be less insulting to people with strokes or brain injuries, but it then undermines her whole premise. The hierarchy of the brain and the mind doesn’t change just because a part of the brain is damaged.

Besides, changes to brain function at any level can change the way a person thinks and behaves. The classic example was Phineas Gage, who in 1848, accidentally blasted an iron rod through his skull, damaging his left frontal lobe. History records that Gage’s well-mannered, pleasant demeanour changed suddenly into a fitful, irreverent, obstinate and capricious man whose workmates could no longer stand him [6]. Medical science has documented numerous cases of damage to the right ventromedial prefrontal cortex causing acquired sociopathy [7]. How can the mind be in control of the brain when an injury to the brain causes a sudden change in thought pattern and behaviour? Clearly one CAN blame the physical brain for one’s decisions and actions. Strike three. You’re out.

Dr Leaf is welcome to comment here. Perhaps she meant something completely different by her post, although there’s only so many ways that such a statement can be interpreted.

Ultimately, Dr Leaf’s love of posting pithy memes of dubious quality is now getting embarrassing. Being so far behind the knowledge of a subject in which she claims expertise is ignominious. Undermining her own premise and contradicting herself is just plain embarrassing. But to be so insensitive to some of the most vulnerable is poor form. I think she’d be well served by re-examining her facts and adjusting her teaching.


  1. Leaf, C.M., Switch On Your Brain : The Key to Peak Happiness, Thinking, and Health. 2013, Baker Books, Grand Rapids, Michigan:
  2. Haggard, P., Human volition: towards a neuroscience of will. Nat Rev Neurosci, 2008. 9(12): 934-46 doi: 10.1038/nrn2497
  3. Goldstein, E.B., Sensation and perception. 8th ed. 2010, Wadsworth, Cengage Learning, Belmont, CA:
  4. Kouider, S. and Dehaene, S., Levels of processing during non-conscious perception: a critical review of visual masking. Philos Trans R Soc Lond B Biol Sci, 2007. 362(1481): 857-75 doi: 10.1098/rstb.2007.2093
  5. Tamietto, M. and de Gelder, B., Neural bases of the non-conscious perception of emotional signals. Nat Rev Neurosci, 2010. 11(10): 697-709 doi: 10.1038/nrn2889
  6. Fumagalli, M. and Priori, A., Functional and clinical neuroanatomy of morality. Brain, 2012. 135(Pt 7): 2006-21 doi: 10.1093/brain/awr334
  7. Mendez, M.F., The neurobiology of moral behavior: review and neuropsychiatric implications. CNS Spectr, 2009. 14(11): 608-20 http://www.ncbi.nlm.nih.gov/pubmed/20173686