From the 2008 Holiday Lectures—Making Your Mind: Molecules, Motion, and Memory

Clive Wearing: A man without memory

Clive Wearing has lost his ability to remember and lives in a perpetual state of having just awoken.

1 minute 15 seconds

Demo: Phrenology

Dr. Kandel illustrates the practice of the now-debunked theory of phrenology.

1 minute 4 seconds

A patient with conduction aphasia

A patient can both comprehend and articulate language, but cannot verbalize what is a clear idea in her mind.

1 minute 9 seconds

Clive Wearing plays piano despite memory deficit

Even though Clive Wearing cannot remember people or events, his piano-playing skills are intact.

1 minute 6 seconds

Demo: SHH concentration and eye position

A reduction in the level of sonic hedgehog (SHH) gene expression can lead to cyclopia.

1 minute 22 seconds

Demo: The electrical activity of Dr. Jessell's arm

A live recording of muscle activity from Dr. Jessell's biceps and triceps muscles.

2 minutes 15 seconds

Growth cones in action

The growth cones of two neurons sense and interact with one another.

34 seconds

Long-distance neuronal path-finding

Retinal axons travel across the brain, reading navigation cues, to find appropriate targets.

31 seconds

Contact repulsion of a growth cone

A growth cone contacts a repellant molecule on another axon, collapses, and withdraws.

1 minute 5 seconds

Computer analysis of human movement

Dr. Jessell's leg muscle activation patterns are recorded during walking.

56 seconds

Demo: Testing a student's proprioceptive reflex

A knee-jerk reflex depends on a simple circuit of proprioceptive sensory neurons and spinal motor neurons.

1 minute 21 seconds

Demo: Proprioception makes raising a mug easy

The average person has no difficulty raising a coffee mug.

52 seconds

Without proprioception, raising a mug is difficult

A person with a disease that kills proprioceptive neurons has severe problems with the simplest of movements.

1 minute 36 seconds

Behavior of mice that lack proprioception

Genetically engineered mice lacking proprioceptive sensory axons are not capable of well-coordinated walking.

25 seconds

Walking versus hopping

In a giraffe's walk, left and right limbs move alternately, while in a kangaroo's hop, opposing limbs move together.

1 minute 12 seconds

Dr. Jessell's muscle activity when he hops or walks

Electrical activity recorded from the leg muscles reveals different patterns of activation during different gaits.

45 seconds

Mutant mice with crossed excitation hop

Kangaroo-like hopping when spinal cord excitatory interneurons cross the midline to stimulate both sides.

1 minute 18 seconds

Ian Waterman: Compensating for proprioceptive loss

In the absence of proprioceptive feedback, some individuals can compensate by using visual feedback.

1 minute 41 seconds

Demo: Touching thumb to fingers with proprioception

Proprioceptive feedback makes it easy to touch one's thumb to one's fingers without looking.

57 seconds

Waterman touching thumb to fingers without feedback

In the absence of proprioception and visual feedback, it is impossible to touch thumb to fingers accurately.

1 minute 15 seconds

Demo: Using spatial memory to clear an obstacle

Even without visual feedback, we are able to negotiate an obstacle using spatial memory.

2 minutes 9 seconds

Cat remembers obstacle location for many minutes

Even when distracted by food, the cat's brain encodes and retains the location of an obstacle.

1 minute 39 seconds

Demo: Meet a live Aplysia californica

Aplysia californica is a marine snail with a simple nervous system suitable for research on learning and memory.

1 minute 40 seconds

Aplysia's gill-withdrawal reflex and sensitization

A touch to the Aplysia's siphon causes a gill withdrawal, a simple reflex for studying memory.

1 minute 25 seconds

Mice navigate a Barnes maze to test spatial learning

Mice can be trained to use spatial cues to navigate a maze that tests their ability to remember specific locations.

2 minutes 14 seconds

Visualizing learning

Dr. Harshad Vishwasrao guides you through a collection of images showing neuronal growth and synaptic formation representative of anatomical changes that occur during learning.

5 minutes 39 seconds

Interview with Dr. Thomas Jessell

An interview with Dr. Jessell.

6 minutes 12 seconds

Interview with Dr. Eric Kandel

An interview with Dr. Kandel.

6 minutes 20 seconds

Interview with Dr. Adam Hantman

An interview with Dr. Adam Hantman, a post-doctoral student in Thomas Jessell's lab.

3 minutes 25 seconds

Interview with Tessa Hirschfeld-Stoler

An interview with Tessa Hirschfeld-Stoler, a lab technician in Eric Kandel's lab.

3 minutes 23 seconds

Interview with Priya Rajasethupathy

An interview with Priya Rajasethupathy, an M.D./Ph.D. student in Eric Kandel's lab.

3 minutes 44 seconds

Interview with Dr. Laskaro Zagoraiou

An interview with Dr. Laskaro Zagoraiou, a post-doctoral student in Thomas Jessell's lab.

3 minutes 31 seconds

From the 2003 Holiday Lectures—Learning From Patients: The Science of Medicine

Learning from Mice: The Science of Transgenic Technology

What do humans, flies, and worms have in common? More than you might think. See how transgenic organisms are engineered, and how they enable researchers to study genetic diseases.

11 minutes 7 seconds

Spinocerebellar Ataxia Case Study

Dr. Huda Zoghbi interviews Milan Cloud, a patient who has inherited the neurological disorder spinocerebellar ataxia 1, or SCA1.

3 minutes 29 seconds

Rett Syndrome

Dr. Zoghbi introduces the topic of Rett syndrome by showing how development usually progresses in a young girl. She then shows an excerpt from Silent Angels, introduced by Julia Roberts, which shows how Rett syndrome affects development.

2 minutes 51 seconds

Rett Syndrome Mouse

Dr. Zoghbi shows how a mouse that has been given the gene responsible for Rett syndrome exhibits some of the same neurological symptoms as human Rett patients.

1 minute 13 seconds

SCA1 Mouse on Rotarod

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.

34 seconds

Interview with Dr. Huda Zoghbi

An interview with Dr. Zoghbi.

5 minutes 51 seconds

Interview with Jennifer Gatchel

An interview with Jennifer Gatchel, a scientist in Dr. Zoghbi's lab.

4 minutes 50 seconds