Subliminal, by Leonard Mlodinow (2012)

Once attention is called to them, it is easy to accept many of our simple behaviors [...] as being automatic. The real issue is the extent to which more complex and substantive behaviors, with the potential to have a much greater impact on our lives, are also automatic - even though we may feel sure that they are carefully thought through and rational.

[...] many unconscious processes can never be directly revealed through the kind of self-reflection encouraged by therapy, because they transpire in areas of the brain not open to the conscious mind.

People have a basic desire to feel good about themselves, and we therefore have a tendency to be unconsciously biased in favor of traits similar to our own, even such seemingly meaningless traits as our names. Scientists have even identified a discrete area of the brain, called the dorsal striatum, as the structure that mediates much of this bias.

[...] more elegant restaurants commonly offer menus peppered with terms like "crispy cucumbers", "velvety mashed potatoes", and "slow-roasted beets on a bed of arugula" [...]

Studies show that flowery modifiers not only tempt people to order the lyrically described foods but also lead them to rate those foods as tasting better than the identical foods given only a generic listing.

[...] subjects were given three different boxes of detergent and asked to try them all out for a few weeks, then report on which they liked best and why. One box was predominantly yellow, another blue, and the third was blue with splashes of yellow. In their reports, the subjects overwhelmingly favored the detergent in the box with mixed colors. Their comments included much about the relative merits of the detergents, but none mentioned the box. [...] But in reality it was just the box that differed - the detergents inside were all identical.

[...] four French and four German wines, matched for price and dryness, were placed on the shelves of a supermarket in England. French and German music were played on alternate days from a tape deck on the top shelf of the display. On days when the French music played, 77 percent of the wine purchased was French, while on the days of German music, 73 percent of the wine purchased was German.

Studies have indeed shown that when wines are tasted blind, there is little correlation between a wine's taste and its cost, but that there is a strong correlation when the wines are not sampled blind. [...] the study was conducted while the subjects were having their brains scanned in an fMRI machine. The resulting images showed that the price of the wine increased activity in an area of the brain behind the eyes called the orbitofrontal cortex, a region that has been associated with the experience of pleasure. So though the two wines were not different, their taste difference was real, or at least the subjects' relative enjoyment of the taste was.

Our brains are not simply recording a taste or other experience, they are creating it.

Our unconscious doesn't just interpret sensory data, it enhances it. It has to, because the data our senses deliver is of rather poor quality and must be fixed up in order to be useful. [...]

To help compensate for their imperfections, your eyes change position a tiny bit several times each second. These juggling motions are called microsaccades [...]. These happen to be the fastest movements executed by the human body, so rapid that they cannot be observed without special instruments. [...]

If your eyes were a simple video camera, all that motion would make the video unwatchable. But your brain compensates by editing out the period during which you eye is in transit and filling in your perception in a way that you don't notice.

Another gap in the raw data delivered by your eyes has to do with your peripheral vision, which is quite poor. In fact, if you hold your arm out and gaze at your thumbnail, the only part of your field of vision with good resolution will be the area within, and perhaps just bordering, your nail. Even if you have twenty-twenty vision, your visual acuity outside that central region will be roughly comparable to that experienced by a person who needs thick glasses and doesn't have them.

The world we perceive is an artificially constructed environment whose character and properties are as much of a result of unconscious mental processing as they are a product of real data.

In modern terms, the starting point in understanding how memory works is Münsterberg's realization that the mind is continuously bombarded by a quantity of data so vast that it cannot possibly handle all of it - the roughly eleven million bits per second I mentioned in the last chapter. And so we have traded perfect recall for the ability to handle and process that staggering amount of information.

Linguists recognize two types of language structure: surface structure and deep structure. Surface structure refers to the specific way an idea is expressed, such as the words used and their order. Deep structure refers to the gist of the idea. Most of us avoid the problems of clutter by retaining the gist but freely discarding the details. As a result, although we can retain deep structure - the meaning of what was said - for long periods of time, we can accurately remember surface structure - the words in which it was said - for just eight to ten seconds.

Think back on your life. What do you remember? When I do that, I find that it is not enough. Of my father, who died more than twenty years ago, my memory holds but meager scraps. [...]

I know, when I shower my children with my usual excess of hugs and kisses, that most of these scenes will not stay with them. They will forget, and for good reason. [...] But hugs and kisses do not vanish without a trace. They remain, at least in aggregate, as fond feelings and emotional bonds.

In particular, what seems special about humans is our desire and ability to understand what other people think and feel. Called "theory of mind", or "ToM", this ability gives humans a remarkable power to make sense of other people's past behavior and to predict how their behavior will unfold given their present or future circumstances.

One measure of ToM is called intentionality. An organism that is capable of reflecting about its own state of mind, about its own beliefs and desires, as in I want a bite of my mother's pot roast - is called "first-order intentional". Most mammals fit in that category. [...] A second-order intentional organism is one that can form a belief about someone else's state of mind, as in I believe my son wants a bite of my pot roast. [...] If you have third-order intentionality you can go a step further, reasoning about what a person thinks a second person thinks, as in I believe my mom thinks that my son wants a bite of her pot roast.

The evidence on nonhuman primates seems to show that they fall somewhere between first- and second-order thinking. [...] Humans, on the other hand, commonly engage in third- and fourth-order intentionality and are said to be capable of sixth-order.

Neuroscientists today commonly divide the brain into three crude regions, based on their function, physiology, and evolutionary development. In that categorization, the most primitive region is the "reptilian brain", responsible for basic survival functions such as eating, breathing, and heart rate, and also for primitive versions of the emotions of fear and aggression that drive our fight-or-flight instincts. [...]

The second region, the limbic system, is more sophisticated, the source of our unconscious social perception. [...]

The [third region] neocortex lies above most of the limbic system.

Anatomically, Homo sapiens reached its present form about two hundred thousand years ago, but as I've said, behaviorally, we humans did not take on our present characteristics, such as culture, until about fifty thousand years ago. In the time between the original Homo species and ourselves, the brain doubled in size. A disproportionate share of that growth occurred in the frontal lobe, and so it stands to reason that the frontal lobe is the location of some of the specific qualities that make humans human. [...]

The frontal lobe contains regions governing the selection and execution of fine motor movements - especially of the fingers, hands, toes, feet and tongue [...].

The prefrontal cortex is responsible for planning and orchestrating our thoughts and actions in accordance with our goals, and integrating conscious thought, perception, and emotion; it is thought to be the seat of our consciousness.

We automatically adjust the amount of time we spend looking into another's eyes as a function of our relative social position. [...]

It is not your overall tendency to look at something that is telling but the way in which you adjust your behavior when you switch between the roles of listener and speaker. [...]

Here's how it works: take the percentage of time you spend looking into someone's eyes while you are speaking and divide it by the percentage spent looking at that same person's eyes while you are listening. [...]

That quotient, psychologists discovered, is a revealing statistic. It is called the "visual dominance ratio", and it reflects your position on the social dominance hierarchy relative to your conversational partner. A visual dominance ratio near 1.0, or larger, is a characteristic of people with relatively high social dominance.

In his article [What is an Emotion?], [William] James addressed emotions such as "surprise, curiosity, rapture, fear, anger, lust, greed and the like" which are accompanied by bodily changes such as quickened breath or pulse or movements of the body or face. It may seem obvious that these bodily changes are caused by the emotion in question, but James argued that such an interpretation is precisely backward. "My thesis on the contrary", James wrote, "is that the bodily changes follow directly the PERCEPTION of [an] existing fact, and that our feeling of the same changes as they occur IS the emotion... Without the bodily state following on the perception, the latter would be purely cognitive in form, pale, colorless, destitute of emotional warmth. [...]

Emotions, in today's neo-Jamesian view, are like perceptions and memories - they are reconstructed from the data at hand.

Evolution designed the human brain not to accurately understand itself but to help us survive. [...] But even as we grow to better understand ourselves, we should maintain our appreciation of the fact that, if our mind's natural view of the world is skewed, it's skewed for a reason.