“Consciousness, Dreams & Drugs” — Podcast 2

On the second Connectome podcast, I muse about three of the hottest topics in neuroscience today: what “consciousness” might be, how it relates to dreams, and how drugs can play some strange tricks on that relationship.   Click here to play or download: If the SoundCloud link doesn’t play, you can download the original mp3. Enjoy, and feel free to email us questions and suggestions for next time!   (Produced by Devin O’Neill at The Armageddon Club) Continue reading “Consciousness, Dreams & Drugs” — Podcast 2

The Memory Master

A gene that may underlie the molecular mechanisms of memory has been identified, says a new study. The gene’s called neuronal PAS domain protein 4 (Npas4 to its friends). When a brain has a new experience, Npas4 leaps into action, activating a whole series of other genes that modify the strength of synapses – the connections that allow neurons to pass electrochemical signals around. You can think of synapses as being a bit like traffic lights: a very strong synapse is like a green light, allowing lots of traffic (i.e., signals) to pass down a particular neural path when the neuron … Continue reading The Memory Master

Synaptic Changes

Synapses – the junctions where neurons communicate – are constantly growing and pruning themselves – and those two processes occur independently of one another, says a new study. As a synapse sees more and more use, it tends to grow stronger, while synapses that fall out of use tend to grow weaker and eventually die off. Collectively, these processes are known as synaptic plasticity: the ability of synapses to change their connective properties. But as it turns out, the elimination of redundant synapses isn’t directly dependent on others being strengthened – instead, it seems to be triggered by its own … Continue reading Synaptic Changes

Chemical Parasites

A certain brain parasite actually turns off people’s feelings of fear by increasing levels of the neurotransmitter chemical dopamine, says a new study. Toxoplasma gondii, a parasitic protozoan (a kind of single-celled organism), mostly likes to live in the brains of cats – but it also infects birds, mice, and about 10 to 20 percent of people in the U.S. and U.K. This might sound like science fiction, but plenty of microbiologists will assure you it’s very real. In fact, T. gondii isn’t the only parasite that controls its hosts’ behavior – a fungus called Ophiocordyceps unilateralis makes infected ants climb to the highest point they can find, sprout fungal spore … Continue reading Chemical Parasites

Stress and Balance

Our responses to threatening situations depend on two fear-regulation circuits, a recent study shows. A well-balanced sense of fear is crucial to our survival: too much, and we’d descend into panic attacks every time we were startled. Too little, and we might not react when survival is crucial. As it turns out, this balance is maintained by two opposing brain circuits, both involving corticotropin-releasing hormone (CRH) and its type 1 receptor (CRHR1). The body releases CRH in response to stressful stimuli. This substance creates some pretty interesting effects in different parts of the brain – in areas like the forebrain, hippocampus, and thalamus, it … Continue reading Stress and Balance

Diff’rent Vesicles

A new discovery shows that the rules of synaptic transmission are very different from what we’d thought. In each neuron, tiny sacs called vesicles store neurotransmitter chemicals, and help transport them to other neurons. For decades, scientists had thought all the vesicles of a particular neurotransmitter were more or less identical – but now, they’ve discovered that only one set of vesicles are marked for transmission, while a much larger set lay mysteriously dormant. What causes these differences, you ask? A protein with an awesome name: We now find that the v-SNARE tetanus toxin-insensitive vesicle-associated membrane protein (VAMP7) differs from other … Continue reading Diff’rent Vesicles

Working Off Worry

Want to get rid of gloomy thoughts? Try working some physical activity into your daily routine, says a new study. For people who struggle with depression and anxiety, the research shows, exercise can be just as effective as antidepressant medication. It often prevents symptoms from getting worse – and in some cases, it even helps cure the problem. Doctors have known for decades that a little physical activity can help distract you from your worries, boost positive feelings, and even relieve anxiety and depression. But in recent years, research has shown that exercise’s hidden effects reach much deeper: it tells your body to produce endorphins – natural chemicals that act … Continue reading Working Off Worry