Does knowledge of brain function alter brain function? The development of psychology is based on this premise, either implicitly or explicitly. Where psychologists focus on behaviour as the main measure of interest, linking behaviour directly to brain function has been one of the popular mysteries and goals of neuroscience throughout the last few decades. This may seem to be a relatively simple task at first glance. For instance, great strides have been made in motor and visual neuroscience, where numerous studies have connected the activity of neurons directly to different aspects of motor commands such as planning and muscle engagement. However, there are still many unanswered questions within these subfields such as whether the so-called primary ‘motor’ or ‘visual’ cortices are really just processing basic motor- or visual-related inputs (for some interesting studies on the visual system, see here and here).
Although virtually every brain researcher assumes that behaviour relies* on brain function, a growing number are now focused on how our own brain function can alter itself (mostly through behavioural decisions and actions). From work on the value of meditation and mindfulness to the burgeoning field of neuroeconomics (which combines economic theories and reward/aversion- and decision-related neuroscience to understand why we generally value certain things over others and ultimately make the choices we do), every additional study helps us better outline both our potential limitations as well as our tremendous capacity for change. These ideas have become part of the global consciousness, in part due to books about brain plasticity and in how to use a basic knowledge of neuroscience in your everyday life, as David Rock argues in his well-written and practical book “Your Brain at Work”.
But how does mere knowledge really alter brain function? In a study published this year by Elizabeth Phelps and colleagues at New York University, they found that giving subjects explicit knowledge about the probability of receiving a reward following a cue lead to both better performance and clear changes in brain activity when compared to trial-and-error feedback. Probabilistic knowledge of reward outcomes resulted in less activation of the nucleus accumbens, ventromedial prefrontal cortex and hippocampal area (regions involved in the processing of reward learning and valuation) compared to the no-knowledge, trial-and-error, condition. What’s more, the dorsolateral prefrontal cortex appeared more active for win conditions (when the person guessed correctly based on the cue) when people were given information about the probability of getting a reward. As this region had negative functional connectivity to those noted above, the author’s suggested that the dorsolateral prefrontal cortex may be involved in the on-line dampening of responses in reward-related regions.
So, while contemporary neuroscience is helping us connect behaviour to brain-based activity, we are still left with the gap in how, exactly, we can use this information to alter our future brain function and behaviour – even if there is an exponential growth in the number of companies (some good, most not) that want to convince you, for a fee, that the answer to controlling your own brain’s plasticity lies with them.
* For the philosophically inclined, I realize that the term ‘relies’ could be, strictly speaking, argued against or replaced entirely with other terms. My use of the word here is very general and aims to avoid the discussion altogether – for now.
Li J, Delgado MR, & Phelps EA (2011). How instructed knowledge modulates the neural systems of reward learning. Proceedings of the National Academy of Sciences of the United States of America, 108 (1), 55-60 PMID: 21173266
Moradi F, Buračas GT, & Buxton RB (2011). Attention strongly increases oxygen metabolic response to stimulus in primary visual cortex. NeuroImage PMID: 21839179
Watkins S, Shams L, Josephs O, & Rees G (2007). Activity in human V1 follows multisensory perception. NeuroImage, 37 (2), 572-8 PMID: 17604652