Scientific Cafe 2012: Brain Myths

Last night was BAW's first Scientific Café of 2012, with the topic being "Brain Myths," a topic that I've written about before, and the discussion of which I feel is crucial in dispelling popular misconceptions regarding the brain and its functions as well as being particularly suited to the Café’s general audience.

The guest speakers were Dr. Ed Ruthazer (McGill; Montreal Neurological Institute), Dr. Natasha Rajah (McGill; Douglas Institute), Dr. Michael Fehlings (University of Toronto), and Dr. David Ragsdale (McGill; MNI). I'll provide a quick recap of the topics covered by each of the guests along with some of my own comments.

Dr. Ruthazer focused primarily on experience and perception, and how these originate within the brain. Recent advances in technology have allowed us to make incredible leaps in our understanding of perception; in particular, it's possible to reconstruct one's visual experience using imaging techniques, albeit with (currently) limited accuracy and resolution. As technology advances, it will increasingly become possible to reconstruct one's experiences through analysis of brain activity. Future technology may also lead to a complicated (but fascinating) ethical and philosophical issue: if consciousness is an epiphenomenon of brain activity, and we eventually become capable of producing sophisticated artificial 'brains', what are the consequences of producing artificial intelligence and sentience that mimics or rivals our own?

Dr. Rajah focused on myths related to memory. One common misconception is that our brains act as 'recorders' that faithfully encode events for subsequent accurate retrieval. However, work from Dr. Elizabeth Loftus and others has shown that our own memories are in fact rather fallible, in that memories can be modulated or even (in some cases) inserted, with the manipulated individual confident that their adulterated memories are both accurate and their own. In fact, stating that we believe something reinforces that belief, leading to false confidence in a fallible memory if it is declared often enough. Similarly, repressed memories are controversial in this field, with the general consensus being that traumatic events would normally be remembered to some extent, and that repressed memories are likely to be false memories. Finally, myths regarding memory loss in popular media can be misleading, as common misconceptions regarding amnesia are produced from inaccurate fiction.

Dr. Fehlings lamented the fact that there are very few examples of clinical neuroscientists or neurosurgeons in popular fiction (with Dr. Frankenstein, or his younger Mel Brooks equivalent, as rare examples). In the scientific world, however, we are rapidly gaining an understanding of brain regeneration and repair following injury. One example he mentioned is adult neurogenesis, which I've previously written about here, as well as the therapeutic potential of implanted neural stem cells. In closing, he stressed the importance of translational research, in which new insight into brain repair and regeneration gleaned from basic science is applied at a clinical level to patients of neurotrauma.

Finally, Dr. Ragsdale focused on more philosophical concerns related to neuroscience. In particular, if the mind is an epiphenomenon of brain activity, what is the mechanism by which this occurs? If our consciousness is a product of deterministic forces (i.e. underlying neurobiology and its features), do we actually have free will? One experiment exploring the latter described how the neural activity underlying a voluntary action actually precedes the conscious decision to perform the action by roughly a half-second. So if our brains are making our decisions for us, is free will an illusion? He concluded with the importance of creative thinking in neuroscience research, in that our understanding of our brain is still very incomplete, and so there is still lots of room for wild new ideas about the brain to lead to insight about ourselves.

If you couldn't make it to the event, I hope this provided a rough explanation of the type of topics covered. I would definitely recommend checking out any future Science Cafés, as they're stimulating and worthwhile events that make complicated topics accessible to a general audience.

The origins of empathy?

Neuroscience is uniquely suited to investigate the biological underpinnings of the features and traits that make us human, including morality, complex emotions and higher-order cognition. However, as we continually learn more about our behaviour and its origins, one unavoidable and startling possibility is frequently made clear; many quintessentially 'human' characteristics may not be unique to ourselves. One recent example is empathy, the experience of feeling and understanding the state of another agent. Empathy may cause one to respond altruistically; for example, to relieve the suffering or discomfort of another in unfortunate circumstances. Biologists have found evidence of altruistic behaviour across the animal kingdom, presumably due to evolutionary pressures favouring those behaviours that promote species survival and not due to active cognition. However, recent studies have raised the startling possibility that the experience of empathy may be older (evolutionarily) than we think, that we may not be alone in our understanding of the states of others, and that our own understanding of the mental states of animals may be even more primitive than we hold them to be.

Some of the recent evidence suggesting that rodents may have the capacity for empathy comes from pain research here at McGill. Mice in the presence of another mouse in pain are more sensitive to pain themselves, but only if the mouse is familiar (a 'roommate', essentially), and not if the alternate mouse is unfamiliar. To put it another way, if a mouse sees a 'friend' in pain, their understanding (such as it is) of the familiar mouse's experience can affect their own perception of pain, as part of a phenomenon termed “emotional contagion” that is believed to be a precursor to empathic behaviour.

A brand-new study has potentially added some exciting insight to the issue of empathy precursors in animals. A team from the University of Chicago developed a novel method of examining empathy-related behaviour, in which one rat is held in a restraining device that can be released by another rat. After learning how to open the restraining cage, the freely-moving rat chose to free its restrained companion, but not empty restrainers or those containing a toy rat. Notably, female rats seemed to show more altruistic behaviour than males. In a subsequent experiment, this team showed that if a second restrainer containing chocolate was placed alongside a trapped rat, the free rat was equally likely to initially open the chocolate restrainer (and enjoy the chocolate alone) or to open the rat restrainer and share the chocolate, suggesting that freeing the trapped companion is as motivating to the rat as a tasty treat. The authors of this study suggest that these results indicate empathy on the part of the freely-moving rat, in that it is highly motivated to rescue a companion animal that it perceives as distressed, even when doing so costs the rat resources (in terms of sharing the chocolate).

However, is this really the case? In the scant time since this article was published, alternative explanations for the rats' behaviour have arisen. One possibility is that the freely-moving rat becomes distressed by the trapped rat (either by their vocal cries, a released scent, or another signal), and the free rat is opening the restrainer to extinguish these cues and reduce its own distress, as opposed to 'helping' the other rat. Supporting this hypothesis, the animals emitted more frequent 'alarm calls' when an animal was trapped, explaining why the free animals were more motivated to open only those cages containing a trapped companion. This would not be empathic behaviour, as the freely-moving rat is merely acting to reduce its own distress, rather than altruistically 'rescuing' the trapped rat. In addition, the evolutionary advantages of empathic experiences in rodents are unclear.

So the animal empathy issue, new as it is, remains somewhat murky. It seems that rodents possess the capacity for emotional contagion, a primitive precursor for actual empathy. The more recent research raises the possibility for empathy underlying altruistic behaviour in rats, although the evidence so far is insufficient to conclude that this is the case. However, these studies provide clear research directions for future studies investigating the origins of our own uniquely human condition. We already know that human infants display empathy- and morality-related behaviour, as well as a basic understanding of the mental experiences of others (“theory of mind”), as early as one to two years of age. Taken together, these avenues of research bring us closer to understanding the evolutionary and developmental origins of those traits that make us human, to whatever extent we can say they remain uniquely ours.

[Adapted from a post originally posted here.]