Stimulating Neural Circuits with Magnetism

Brain stimulation might sound like some Frankensteinian demonstration from a Victorian science fair. But in reality, it is a contemporary technique making a huge impact in neuroscience by addressing a longstanding limitation of traditional methods for investigating human brain function. Such techniques, like EEG and fMRI, can only be used to infer the effects of a stimulus or task on brain activity, and not vice versa. For example, a scientist might use EEG to study the effect of a task like arm movement on brain activity, but how can one study the effect of brain activity on arm movement?Continue reading

Zebrafish

What Zebrafish Teach Us About Touch

Unlike the sense of vision, which is perceived only by light-sensitive photoreceptors in our eyes, the mechanoreceptors that respond to light touch are located in sensory neurons all over the body.  Our sense of touch starts in the skin, where sensory neurons with elaborate dendrites just below the skin’s surface provide dense coverage over the entire area of the body.  When we touch something, the mechanical pressure created by the contact between an object and our skin opens mechanoreceptors that cause the sensory neuron to fire an action potential and activate downstream neurons.  We are constantly coming into physical contact with objects and people in our environment, and as a result a large number sensory neurons are being activated over many different areas of our body at any given moment!  How does the nervous system handle all of this incoming tactile information?Continue reading

A Tale of Two Aphasias

Paul Broca
Paul Broca

It’s 1861, and the French neurologist Paul Broca is examining a new patient. Dr. Broca is puzzled because all the patient can say is “tan.” When Dr. Broca asks him questions, Tan cannot seem to form the words. However, it is clear that Tan can understand language because, when he asked to whistle or sing a melody, he can do so without a problem. Something is wrong with his ability to speak! When he is asked to speak grammatically or create complete sentences, he cannot do it – not even in writing! Dr. Broca doesn’t know what to do for Tan, since he knows that Tan must have brain damage… but where?Continue reading

Bend it like Beckham: The Neuroscience Way

Life is a continuum of learning motor skills to achieve goals.  At a young age, children learn how sit up, walk, jump, and then cut with scissors.  Later, they may learn how to play soccer or piano, but they will probably not be as proficient as professional athletes and musicians unless they dedicate their lives to perfecting that skill.  So, how does practice make us more perfect?  Here are suggested guidelines for efficient motor skill learning that neuroscience studies have proposed.Continue reading