Varying concentrations of a signaling molecule activate different transcription factors and determine cell fate.
Illustrates how studying one family's pedigree can reveal an entire history of passing on a genetic disorder such as SCA1.
The growth cone of a neuron avoids repellant molecules and navigates to innervate the appropriate muscle.
Prialt does not block the mammalian motor synapse, but blocks the pain pathway in the spinal cord.
Prialt, a drug derived from cone snail venom, paralyzes fish by blocking calcium channels at a motor synapse.
Neurons in the cortical area 5 are active when a cat is straddling an obstacle.
Multiple cone snail toxins attack different molecules of the nervous system and cause paralysis.
Electrical and chemical signals are used by neurons to communicate with one another at contact points called synapses.
Long-term memory requires the activation of CREB, turning on specific genes that support new synaptic growth.
A dramatic illustration of how hearing happens in the ear.
The fetal brain grows enormously during pregnancy, both in terms of its size and the number of neurons it has.
Early LTP (short-term memory) depends on a calcium-dependent protein kinase to strengthen an existing synapse.
Late LTP (long-term memory) involves dopamine activation of CREB to support new synaptic growth.
Illustrates how providing leptin to an obese mouse rapidly rewires its hypothalamus neurons.
Some cone snail toxins chemically hyperactivate neurons and immobilize prey, much like a Taser.
Aplysia californica is a marine snail with a simple nervous system suitable for research on learning and memory.
A touch to the Aplysia's siphon causes a gill withdrawal, a simple reflex for studying memory.
A live recording of muscle activity from Dr. Jessell's biceps and triceps muscles.
Even when distracted by food, the cat's brain encodes and retains the location of an obstacle.
Dr. Jessell's leg muscle activation patterns are recorded during walking.
A patient can both comprehend and articulate language, but cannot verbalize what is a clear idea in her mind.
A growth cone contacts a repellant molecule on another axon, collapses, and withdraws.
This species of cone snail immobilizes its prey in a split second with lightning-strike cabal toxins.
Larger cone snails produce more venom and are more dangerous to human beings in an accidental stinging.
The growth cones of two neurons sense and interact with one another.
In the absence of proprioceptive feedback, some individuals can compensate by using visual feedback.
Electrical activity recorded from the leg muscles reveals different patterns of activation during different gaits.
An interview with Dr. Kandel.
Retinal axons travel across the brain, reading navigation cues, to find appropriate targets.
An interview with Dr. Michael McIntosh, who discovered the drug Prialt while working as an undergraduate in Dr. Olivera's lab.
Mice can be trained to use spatial cues to navigate a maze that tests their ability to remember specific locations.
Kangaroo-like hopping when spinal cord excitatory interneurons cross the midline to stimulate both sides.
The average person has no difficulty raising a coffee mug.
Genetically engineered mice lacking proprioceptive sensory axons are not capable of well-coordinated walking.
A knee-jerk reflex depends on a simple circuit of proprioceptive sensory neurons and spinal motor neurons.
Dr. Zoghbi demonstrates how mice that have been given the gene responsible for spinocerebellar ataxia 1 (SCA1) are tested on a device called a rotarod to quantify the amount of ataxia present.
A reduction in the level of sonic hedgehog (SHH) gene expression can lead to cyclopia.
Even without visual feedback, we are able to negotiate an obstacle using spatial memory.
Dr. Huda Zoghbi interviews Milan Cloud, a patient who has inherited the neurological disorder spinocerebellar ataxia 1, or SCA1.
Proprioceptive feedback makes it easy to touch one's thumb to one's fingers without looking.
Dr. Jason Biggs of the University of Guam Marine Laboratory discusses the anatomy of cone snails and introduces us to a variety of cone snail species with different tactics to hunt and capture their prey.
Dr. Harshad Vishwasrao guides you through a collection of images showing neuronal growth and synaptic formation representative of anatomical changes that occur during learning.
In a giraffe's walk, left and right limbs move alternately, while in a kangaroo's hop, opposing limbs move together.
In the absence of proprioception and visual feedback, it is impossible to touch thumb to fingers accurately.
Even though Clive Wearing cannot remember people or events, his piano-playing skills are intact.
Clive Wearing has lost his ability to remember and lives in a perpetual state of having just awoken.
A person with a disease that kills proprioceptive neurons has severe problems with the simplest of movements.
An interview with Dr. Laskaro Zagoraiou, a post-doctoral student in Thomas Jessell's lab.
What medical secrets do venomous snails hold? How can listening in on bacterial conversations help develop new antibiotics? In four presentations, Dr. Bonnie L. Bassler and Dr. Baldomero M. Olivera reveal how a deeper understanding of nature and biodiversity informs their research into new...
Venomous carniverous cone snails are a rich source of molecules for scientific research and potential drug development.