The Departure of Skill Memories from Motor Cortex: Deeper Directions for Neuroscience

You probably have certain skills that I don’t.  Each of us, having spent enough time practicing something new, can become an expert.  A simple, ubiquitous example is driving a car with a manual transmission.  The precise sequence and timing of controlling the clutch, giving gas, and shifting the gears are challenging to coordinate when initially learning to drive a stick shift.  But eventually, the precision with which we can perform these sequences of movements is impressive.  Specifically, the errors we make when learning, indicated by gear grinding and stalling, are reduced with repeated practice.  Skill learning is relatively easy to train both in humans and in animals.  It therefore serves as a great way to study how the brain forms memories and uses those memories in the future.Continue reading

Blondes or Brunettes: It’s All About Conditioning

Like it or not, we all have preferences in choosing romantic partners.  Piercings, freckles, hair color, eye color, body physique – through adolescence and into adulthood, we begin to develop sexual preferences to help guide our choice in whom to talk to, whom to date, and whom to marry.  While it’s tempting to attribute these tendencies to hormonal activity, much of our mate preference is due to classical conditioning.  Much like aversion (which has already been thoroughly studied in the context of fear conditioning), sexual preferences may also be an example of classical conditioning.Continue reading

Intracranial EEG and Mental Time Travel

A familiar progression of chords blares out of your speakers as the red lights of the surrounding traffic fade into the memory of a dark stage illuminated by pulsing neon lights.  You replace your current discomfort (horrendous traffic!) with the memory of the last concert you attended – reliving the percussive sensory experience and feeling the intensity of the vibrating sound waves.  As you bust out the occasional air guitar move and tap out the beat on your dashboard, you are successfully retrieving a memory and reinstating a specific pattern of neural activity.  This mental time travel enables you to escape the confinement of your surrounding environment and plunge into the memory of enjoyable past experiences.Continue reading

Dendritic Spines Knowing Neurons

Keeping Memories Fresh by Keeping Glutamate In Check

We are another year older, perhaps a little wiser, and probably more forgetful.  Indeed, making memories is quite a process in the brain: specific synaptic connections are strengthened and new proteins are synthesized.  But as we age, the synapses that make up our memories, such as those in the hippocampus and prefrontal cortex, start to change and can be lost altogether.  The detrimental synaptic alterations may not be permanent, however, and maintaining the health of these synapses may be the key to preventing age-related cognitive decline.Continue reading