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

Development of the human embryonic brain

The fetal brain grows enormously during pregnancy, both in terms of its size and the number of neurons it has.

1 minute 40 seconds

Molecular activity in Aplysia long-term memory

Long-term memory requires the activation of CREB, turning on specific genes that support new synaptic growth.

1 minute 39 seconds

Molecular activity in Aplysia short-term memory

Short-term memory relies on serotonin activating a protein kinase to modify existing synaptic strength.

2 minutes 30 seconds

Molecular basis of early LTP (short-term memory)

Early LTP (short-term memory) depends on a calcium-dependent protein kinase to strengthen an existing synapse.

1 minute 28 seconds

Molecular basis of late LTP (long-term memory)

Late LTP (long-term memory) involves dopamine activation of CREB to support new synaptic growth.

56 seconds

Molecular mechanism of synaptic function

Electrical and chemical signals are used by neurons to communicate with one another at contact points called synapses.

1 minute 9 seconds

Neurons in parietal cortex are active during straddling

Neurons in the cortical area 5 are active when a cat is straddling an obstacle.

1 minute 3 seconds

Repellant ephrin signals guide limb innervations

The growth cone of a neuron avoids repellant molecules and navigates to innervate the appropriate muscle.

1 minute 35 seconds

Signal molecules trigger transcription factors

Varying concentrations of a signaling molecule activate different transcription factors and determine cell fate.

2 minutes 4 seconds

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

Exclusion Mapping

A useful technique for narrowing down the location of a gene involves comparing the chromosomes of affected siblings. Two sisters with Rett syndrome allow researchers an opportunity to map the most likely location of the gene by excluding areas of the chromosome that are not alike. Includes audio narration.

32 seconds

MECP2

This animation shows how the protein MECP2, in conjuction with another protein complex, can act as an "on-off' switch for gene expression. Includes audio narration.

43 seconds

The Proteasome

A 3D animation showing how proteins in the cell are tagged for disposal and degraded by the proteasome. Includes audio narration.

1 minute 43 seconds

SCA1 Pedigree

Illustrates how studying one family's pedigree can reveal an entire history of passing on a genetic disorder such as SCA1.

30 seconds

Tri Nucleotide Repeat

Slippage during DNA replication can lead to expanding sections of repeating nucleotides. Watch this animation to see how this problem occurs. Includes audio narration.

1 minute 7 seconds

X Inactivation

This animation shows how the random deactivation of one of the X chromosomes in a pair can lead to a mozaicism in the expression genes. Includes audio narration.

55 seconds

From the 1997 Holiday Lectures — Senses and Sensitivity: Neuronal Alliances for Sight and Sound

The Cochlea

A dramatic illustration of how hearing happens in the ear. Includes audio narration.

1 minute 30 seconds