on 02-Aug-2018 (Thu)

Number theory (or arithmetic or higher arithmetic in older usage), is a branch of pure mathematics devoted primarily to the study of the integers. It is sometimes called "The Queen of Mathematics" because of its foundational place in the discipline.^[1] Number theorists study prime numbers as well as the properties of objects made out of integers (e.g., rational numbers) or defined as generalizations of the integers (e.g., algebraic integers).

Tasks that are difficult to learn are the most effective, If they simply exercised, they didn’t retain the neurons. Learning must occur, and it must require some effort. So if you exercise, you will produce more neurons. If you do mental training you’ll keep alive more cells that you produced. And if you do both, now you have the best of both worlds: you’re making more cells and keeping more alive. The effort part is key. We need to learn things that are new, and we need to keep it challenging.”

London physician John Langdon H. Down was the first to describe the disorder that would eventually bear his name, in a remarkable paper published in 1866 under the title “Observations on an Ethnic Classification of Idiots.”

Down proposed that they could be classified based on what he considered to be a resemblance to various ethnicities: Caucasian, Ethiopian, Malay, and—infamously—Mongolian.

A combination of drugs designed to raise norepinephrine levels in the brain normalized mice’s learning abilities.

Fear is a basic, automatic response to a specific object, situation, or circumstance that involves a recognition (perception) of actual or potential danger.

In terms of cognitive therapy, the main characteristic of fear is a thought of imminent threat or danger to one’s safety.

Anxiety, in contrast, is a much more prolonged, complex emotional state that is often triggered by an initial fear. For example, you could feel anxious about going to visit friends because they live in an older home that might have spiders or about going to the movies because the film might contain a scene with spiders. The basic fear is of encountering a spider, but you live in a state of persistent anxiety about the future possibility of being exposed to a spider. So anxiety is a more enduring experience than fear. It’s a state of apprehension and physical arousal in which you believe you can’t control or predict potentially aversive future events. Thus you might feel anxious thinking about an important interview, going to a dinner party where you don’t know people, traveling to an unfamiliar place, your performance at work, or a deadline. Notice that anxiety is always future oriented; it is driven by “what if?” thinking. We don’t become anxious over the past, what has already happened; rather, we become anxious over imagined future adverse events or catastrophes: “What if my mind goes blank during the exam?” “What if I don’t get all my work done?” “What if I have a panic attack in the supermarket?” “What if I get the H1N1 influenza virus by being around people?” “What if I encounter someone who reminds me of the assailant who attacked me?” “What if I lose my job?” This enduring emotional state that we call anxiety is the focus of this workbook.