hippocampus

The Department of Defense on Tuesday announced a $40 million investment in what has become the fastest-moving branch of neuroscience: direct brain recording. Two centers, one at the University of Pennsylvania and the other at the University of California, Los Angeles, won contracts to develop brain implants for memory deficits. Their aim is to develop new treatments for traumatic brain injury, the signature wound of the wars in Iraq and in Afghanistan. Its most devastating symptom is the blunting of memory and reasoning. Scientists have found in preliminary studies that they can sharpen some kinds of memory by directly recording, and stimulating, circuits deep in the brain. Unlike brain imaging, direct brain recording allows scientists to conduct experiments while listening to the brain’s internal dialogue in real time, using epilepsy patients like Ralph or people with Parkinson’s disease as active collaborators.

A team of University of Wisconsin-Madison researchers recently showed these kinds of stressors, experienced in early life, might be changing the parts of developing children’s brains responsible for learning, memory and the processing of stress and emotion. These changes may be tied to negative impacts on behavior, health, employment and even the choice of romantic partners later in life. “We haven’t really understood why things that happen when you’re 2, 3, 4 years old stay with you and have a lasting impact,” says Seth Pollak, co-leader of the study and UW-Madison professor of psychology. Yet, early life stress has been tied before to depression, anxiety, heart disease, cancer, and a lack of educational and employment success, says Pollak, who is also director of the UW Waisman Center’s Child Emotion Research Laboratory.

Findings suggest that astrocytes in the mossy fiber system may act as a switch that reacts to large amounts of neuronal activity by raising their levels of calcium. These calcium increases occur over multiple seconds, a relatively long time period compared to that seen in neurons. The spatial extent of the astrocyte calcium increases was also relatively large in comparison to the size of the synapse.

Because several neuropsychiatric disorders are associated with altered social behaviors, findings raise the possibility that CA2 dysfunction may contribute to these behavioral changes.

During his lifetime, Henry G. Molaison (H.M.) was the best-known and possibly the most-studied patient of modern neuroscience. Now, thanks to the postmortem study of his brain, based on histological sectioning and digital three-dimensional construction led by Jacopo Annese, PhD, at the University of California, San Diego, scientists around the globe will finally have insight into the neurological basis of the case that defined modern studies of human memory.

The researchers verified the prediction by injecting drugs that would either expand or decrease the space between cells. The closer the cells, the faster the transmission. The more distant the cells, the slower the transmission until—at a certain distance—the signal failed to propagate.

Memories of events, known as episodic memories, always contain three elements — what, where, and when. Those memories are created in a brain structure called the hippocampus, which must coordinate each of these three elements.

Researchers at Albert Einstein College of Medicine of Yeshiva University used advanced imaging techniques to provide a window into how the brain makes memories. These insights into the molecular basis of memory were made possible by a technological tour de force never before achieved in animals: a mouse model developed at Einstein in which molecules crucial to making memories were given fluorescent “tags” so they could be observed traveling in real time in living brain cells.

Neuroscientists from the University of Leicester, in collaboration with the Department of Neurosurgery at the University California Los Angeles (UCLA), are to reveal details of how the brain determines the timing at which neurons in specific areas fire to create new memories.