Review written by Amy Ciceu (NEU, 2024)
Adeno-associated viruses (AAVs) are some of the most widely used recombinant viral technologies—those that combine different genes to produce unique viral vectors, or tools that convey genetic material into cells—in modern neuroscience. Because they are incapable of being replicated within cells, recombinant AAVs are commonly used in neuroscience research as a means of expressing genes in specific cells. By expressing genes that heighten or dampen the function of certain cells, researchers are able to identify the functions of particular neural circuits.1 This approach can provide scientists with insight into the mechanisms underlying neurobiological processes. To make such circuit-related discoveries, AAVs are typically injected into certain brain regions of animal subjects. After an incubation period, some AAVs encoding fluorescent tracers can induce cells to fluoresce under specialized microscopes, enabling scientists to visualize particular neural circuitry. Furthermore, AAVs have demonstrated clinical potential; for example, AAVs have been used to replenish certain proteins in the treatment of diseases like congenital blindness 2, 3 and spinal muscular atrophy.4, 5 AAV is also currently being investigated as a potential means of treating other brain disorders, including Parkinson’s disease, Alzheimer’s disease, amyotrophic lateral sclerosis (ALS), and more.6
Review written by Amy Ciceu (2024)
Have you ever found yourself in deep thought in a public setting only to come to your senses and arrive at the uncomfortable realization that you’re making eye contact with another person? Such is the dilemma that faces us when we lose control of our awareness. Awareness—a module of behavior that allows us to be conscious of stimuli in our environment—is fundamentally distinct from but similar to attention—the process of selectively focusing the mind on certain stimuli at the expense of others. In an insightful new study led by graduate student Andrew Wilterson of the Graziano Lab at Princeton University, researchers used stimulus-prediction tasks and MRI imaging to investigate the interrelated nature of awareness and attention in the human brain.
Review written by Amy Ciceu (2024) & Adelaide Minerva (PNI, G2)
As youngsters, we develop memories of and connections to our parents, who nurture us throughout not only our childhoods but also much of our lives. These memories and relationships play vital roles in teaching us how to navigate the world. Do other animals form similar memories? A recent study published by the Gould Lab in Princeton’s departments of Psychology and Neuroscience discovered that mouse pups form memories of their maternal caregivers within days of birth and that these memories endure as the pups age into adulthood.
Written by Paula Brooks (PNI, G4)
Walking through your old high school might release a flood of memories that were locked away for years, perhaps even a decade (or more)! Walking through the cafeteria might remind you of the time you almost scared the timid new girl when you boldly walked up to her to invite her to join your friend group for lunch. Or maybe, going past the gym might bring back the memory of when you face planted in front of the entire class while attempting to do the high jump. (Full disclosure: Both of these things happened to me.)
Review written by Renee Waters (PSY, G2)
Have you ever wondered how you can recognize a familiar friend in a busy environment? Or maybe how you remember a person you’ve seen just once? Social memory is the ability to recognize familiar others and is an essential function across species, not only for safety but also to maintain stable structures in complex and dynamic social networks. Social memory is involved in hierarchy formation, and defense, as well as mate, offspring, and interspecies recognition. A region of the brain called the hippocampus has long been pinpointed for its role in learning and memory generally; however, great strides have been taken recently to understand its role in social memory more specifically.
Review written by Paula Brooks (PNI)
Imagine that you are binge-watching Netflix. In spite of the algorithm’s calculations, you are getting bored by the show that was suggested and you are thinking about stopping before the end of the season. However, to your great surprise, a new character enters halfway through the season and you are hooked. The plot has gotten more interesting and the acting has suddenly improved. What just happened?
Review written by Rebekah Rashford (PNI)
There is much consensus that negative stressful early life experiences impact the development of an individual. Numerous studies in humans have linked childhood adversity (e.g., loss of a caregiver, abuse, natural disaster, etc.) to an increased risk for depression and other psychiatric disorders in adulthood. In other words, the more an individual has experienced negative stressors in childhood, the more likely that individual is to develop depression or anxiety when they experience mild stressors in adulthood. This heightened sensitization and increased risk of mood disorders in humans has a parallel observation in rodents, specifically mice, which are used as model organisms in the discussed study. Principal Investigator Catherine Jensen Peña and colleagues at the Icahn School of Medicine at Mount Sinai were interested in exploring the epigenetic effects of such early life stressors on reward circuitry in the brain. Throughout this work the authors posit, as does much of the early life stress (ELS) field, that there could be epigenetic mechanisms at work leading to the aforementioned risk of mood disorder development.
Review written by Jess Breda (PNI)
Have you ever wondered how information is transferred from one brain to another? This process can occur in a variety of ways, from verbal storytelling to simple hand gestures, and across different backgrounds, such as a flight attendant instructing a first time flyer, or a casual conversation with a friend. We gain information from others on a daily basis. However, to study this on a biological level requires the complicated task of recording from two brains experiencing the same stimuli and aligning their activity in time.
Review written by Renee Waters (PSY)
Humans tend to make individual choices based on a series of past experiences, decisions, and outcomes. Just think about the last time you had some terrible take out: you might decide not to eat at that particular restaurant again based on your previous experience. Maybe, you take the same route to work every day because, in the past, there is less traffic on this particular route. The effects that past experiences have on choices are often termed sequential biases. These biases are present everywhere, especially in value-based decision making. You might wonder, what are the neural mechanisms driving this phenomenon? Christine Constantinople, a former postdoc at Princeton University and now an assistant professor at NYU, began to explore this question along with colleagues in the Brody Lab at Princeton.
Review written by Eleni Papadoyannis (PNI)
How do humans control a complex system like the brain? Over the years, neuroscientists have discovered numerous methods to do exactly that. Applying chemicals, such as muscimol, can drive inhibition to shut down a brain region. Alternatively, shining light can selectively activate certain cell types through the photo-sensitive protein channelrhodopsin. Sending electrical impulses via electrodes in deep brain stimulation (DBS) can also control regional activity in humans. Causal manipulation of the brain not only offers incredible insight into hypotheses relating neural activity to behavior, but also serves as a clinical tool. Electrical and magnetic stimulation methods have been used as therapies for treating patients with a variety of diseases and disorders, such as using DBS to control motor disruption in Parkinson’s. A major limitation with many stimulation methods, however, is that the protocol is static while the brain is plastic—over time, brain responses to stimulation may no longer elicit what was intended as the brain naturally changes.