Quotes from David J. Linden

Clearly, Siberian reindeer are not fighting over drugged urine for its nutrative value.

Experiements that have been devised to inflict even mild social pain (like exclusion form a group task or betrayal by a partner in a gambling game) have demonstrated significant activation of the sinula and the anterior cingulate cortex. Emotional pain isn't just a metaphor: In terms of brain activation, it partially overlaps with physical pain.

Male Amazon river dolphins will even insert thier penises in each other's blowholes in the only known example of nasal sex.* *I refuse to make the obligatory "blowjob" joke here. Science writing is very serious business.

Human sexual and social behavior shares some similaries with that of rodents, but has some important differences as well. It shows much greater variability and individuality, for example, and is less closely tied to the olfactory system. At present, it is tempting to speculate that those of us with cheatin' hearts might have differences in brain dopamine, vasopressin, or oxytocin signaling when compared to our more faithful friends who have adopted the prairie vole lifestyle.

I've never felt better. I've never been healthier…. I run four or five miles, four or five times a week, but I broke both my legs running too much last summer. I had stress fractures in both my tibias from running too much. You know, once you're an addict, you're always an addict, so just because I found something good to do doesn't mean I'm not going to hurt myself doing it.

On average, dopamine receptor density is reduced in the VTA target regions of obese subjects as compared with those lean subjects (a characteristic that can be measured in a brain scanner). But the key question remains: Do obese individuals show reduced dopaminergic activation of VTA target areas in response to food? Is a blunted pleasure response to food involved in obesity?

Francis Crick, co-discoverer of the structure of DNA, arguably the greatest discovery in biology in the twentieth century, famously said, "If you want to understand function, study structure.

What if a chemical, either found in nature or cooked up in a lab, could tap into the motivational circuit and drive dopamine neurons artificially from within the brain? Intriguingly, this may be exactly how drugs of abuse work. Although different drugs of abuse have distinct molecular targets and very different behavioral effects, they all drive the electrical activity of dopamine neurons or the release of dopamine from these cells (while nonaddictive brain-targeted drugs like Prozac do not).5

The dorsomedial striatum, a subregion of the basal ganglia, seems to be critical to goal-directed behavior. If it is damaged, the rat's behavior will quickly become habitual even after limited exposure to a new task. Conversely, damage to the neighboring dorsolateral striatum will lead the rat to be more goal-directed and it will never lapse into habit, even after prolonged training.

Our brains are comprised of around eighty billion neurons interconnected to form an enormous network involving approximately five hundred trillion connections called synapses.

As with any computing device, understanding the brain involves characterizing the properties of its main components (neurons), the nature of their connections (synapses), and the pattern of interconnections (wiring diagram).

Martin Hammer in Menzel's group had discovered a unique neuron, called VUMmx1, that responded to sucrose (a type of sugar) with electrical activity but not to an odor; however, after the odor was delivered, followed shortly by the sucrose reward, VUMmx1 would now respond to the odor.

We also find anticipatory effects from another macronutrient, oral fat. People who chew and spit out real cream cheese on a cracker versus nonfat cream cheese (a.k.a. fake cream cheese) on a cracker have relatively large elevations in triglycerides measured in the blood plasma for hours after.13 This study suggests that whole body lipid metabolism may be regulated by oral sensations of fats.

What differences can we observe in the brains of men and women? Can we use those differences to test the hypothesis that the brains of gay men are more likely to be partly feminized and the brains of lesbians are more likely to be partly masculinized? In

These include a portion of the hypothalamus called INAH3, which is larger in straight men, and a bundle of fibers that connects one side of the brain to the other, called the anterior commissure, which is larger in straight women. While there have been some well-publicized reports suggesting that the size of the anterior commissure and INAH3 are more femalelike in gay men,17 there have yet to be clear, independent replications of these findings.18

A drop of concentrated salt water placed on a rat's tongue causes immediate decreases in the production of urine in order to retain water and maintain salt and water balance of body fluids.

It may be, for example, that one key difference between the brains of straight women and lesbians is the function of a particular protein, like a voltage-sensitive potassium channel, that influences the electrical behavior of certain neurons in a brain circuit that influences sexual and gender-typical behavior.

This process of error correction is so fundamental to our biology that distinct circuits of the brain appear to coordinate learning that results from error. One of these error correction pathways involves the cerebellum.3 The cerebellum receives electrical information from a part of the brain stem called the inferior olive when a sensory prediction error occurs. The cerebellum uses these error signals to predict and correct for errors that might occur in the future.