7.1 An Introduction to Cognition and Thinking

cognition, language, and intelligence

The Brain Scientist An accomplished neuroanatomist, Dr. Jill Bolte Taylor had devoted her career to studying the brains of others. But one winter morning in 1996, she was given the frightening opportunity to observe her own brain in the midst of a meltdown.

AJ Mast/The New York Times/Redux

Dr. Jill sensed that something was terribly wrong, but she could not help feeling mesmerized by the “tranquil euphoria” of her new state of consciousness. She no longer felt separate from the outside world. Like a fluid running fast and free, her body drifted in and out of surrounding space. Memories of the past floated into the distance, everyday worries evaporated, and the little voices in her mind that normally narrated her train of thought fell silent (Taylor, 2006).

Wading in a dreamlike fog, Dr. Jill managed to shower and put on clothes. Then, just as she began visualizing the journey to work, her right arm fell limp like a dead fish. It was paralyzed. At that moment she knew: “Oh my gosh, I’m having a stroke! I’m having a stroke!” (Taylor, 2006, p. 44). Her next thought was: “Wow this is so cool!…How many scientists have the opportunity to study their own brain function and mental deterioration from the inside out?”.

Tangled The tangled intersection of arteries (red) and veins (blue) is an arteriovenous malformation (AVM), the anatomical abnormality that led to Dr. Taylor’s stroke. An AVM is essentially a clump of blood vessels that results when there are no tiny vessels called capillaries linking arteries to veins. Sometimes the vessels of an AVM burst under pressure, allowing blood to pool in the brain; this is called a hemorrhagic stroke (American Stroke Association, 2012; National Institute of Neurological Disorders and Stroke, 2012).

Medical Body Scans/Science Source

Dr. Jill was indeed having a rare form of stroke caused by a defective linkage between blood vessels in the brain. This faulty connection in the central nervous system, known as an arteriovenous malformation (AVM), affects a substantial number of people—about 300,000 in the United States alone (around 0.1% of the population) at any given time. Most individuals born with AVMs are symptomless and unaware of their condition, but about 12% (36,000 people) experience effects ranging in severity from annoying headaches to life-threatening brain bleeds like the kind Dr. Jill was experiencing (National Institute of Neurological Disorders and Stroke, 2012).

Having a backstage pass to her own stroke was a once-in-a-lifetime learning opportunity for a neuroanatomist, but it was also a serious condition requiring an immediate response. Dr. Jill understood that strokes can cause permanent paralysis, sometimes even death. Urgent medical attention was needed. She walked into her home office and took a seat by the phone, racking her brain for ideas of how to get help. The usual strategies like calling 911 or knocking on a neighbor’s door simply did not cross her mind. As she gazed at the phone keypad, a string of digits materialized in her brain. It was the phone number of her mother in Indiana. Calling her mom was certainly an option, but what would she say? Dr. Jill didn’t want to worry her mother, so she sat and waited, hoping that another set of digits would appear.

Finally, another phone number flickered by in two separate chunks—it was her work number. She scrawled down the digits as fast as she could, but looking down at what she had written, she only saw cryptic lines and curves. Fortunately, those lines and curves she saw on the paper matched the set of figures that appeared on the phone keypad. Dr. Jill picked up the receiver and dialed the desk of her coworker and friend, Dr. Stephen Vincent (Taylor, 2006). Steve answered the phone immediately, but his words were incomprehensible to Dr. Jill. “Oh my gosh, he sounds like a golden retriever!” she thought to herself. Mustering all her mental might, she opened her mouth and said, “This is Jill, I need help!” Well, that’s what she hoped she had said. Her own voice sounded like a golden retriever as well (Taylor, 2006, p. 56; TED.com, 2008). Luckily, Steve managed to recognize that the murmurs and cries belonged to his friend Dr. Jill, and before long he was driving her to the hospital (Taylor, 2006).

As blood hemorrhaged into Dr. Jill’s brain, she became increasingly unable to process sensory information, tap into memories, or use language. As she later reflected: “In the course of four hours, I watched my brain completely deteriorate in its ability to process all information” (TED.com, 2008). The bleeding had begun to limit her capacity for cognition.

Cognition. You’ve probably heard the term “cognition” tossed around in conversation, and perhaps you know that it has something to do with thinking. But what exactly do we mean by cognition, and where does it figure in the vast landscape of psychology?

Cognition and Thinking

The study of cognition is deeply rooted in the history of psychology. Early psychologists were intensely focused on understanding the mysterious workings of the mind, often using introspection (examination of one’s own conscious activities) in their studies. With the rise of behaviorism in the 1930s, the emphasis shifted away from internal processes and on to behavior. Researchers shunned thoughts, emotions, and anything they could not observe or measure objectively. In the 1950s, psychologists once again began to probe the private affairs of the mind. Psychology experienced a cognitive revolution, and research on cognition and thinking has flourished ever since.

Cognition is the mental activity associated with obtaining, converting, and using knowledge. But how is this type of mental activity different from thinking? Thinking is a specific type of cognition that requires us to “go beyond” information or to manipulate information to reach a goal. Thinking involves coming to a decision, reaching a solution, forming a belief, or developing an attitude (Matlin, 2009). Cognition is a broad term that describes mental activity, and thinking is a subset of cognition. These definitions are not universally accepted, however; some psychologists consider cognition and thinking to be one and the same activity. However the terms are defined, Dr. Jill was clearly experiencing significant impairments in both cognition and thinking on the morning of her stroke.

HOSPITAL HUBBUB

Bleeding Brain The red zone on the right of the CT scan shows a hemorrhage on the left side of the brain. (Note that the patient’s left is your right.) In Dr. Jill’s case, the bleeding interfered with activity in Broca’s and Wernicke’s areas, impairing her ability to produce and understand language. Her frontal lobe function also deteriorated the morning of the stroke, as illustrated by the difficulty she had in devising a coherent strategy to get medical help.

Scott Camazine/Science Source

Upon arriving at Mount Auburn Hospital, Dr. Jill received a computerized axial tomography (CT or CAT) brain scan. Unfortunately, the cross-sectional slices provided by the scan merged into a troubling picture: a giant hemorrhage in the left side of her brain. According to Dr. Jill, “My left hemisphere was swimming in a pool of blood and my entire brain was swollen in response to the trauma” (Taylor, 2006, p. 68).

Dr. Jill needed urgent, expert attention. She was rushed by ambulance to the emergency room at Massachusetts General Hospital, where she was eventually assigned to a room in the neurological intensive care unit. The hospital scene, with its blinding lights and loud noises, was far too hectic for Dr. Jill’s fragile sensory systems, which had become ultra-sensitive to stimulation. Light assaulted her eyes and scorched her brain “like fire” (Taylor, 2006, p. 67). Hospital workers grilled her with questions that she couldn’t understand. Their words were nothing more than a bewildering racket. “Sound streaming in through my ears blasted my brain senseless so that when people spoke, I could not distinguish their voices from the underlying clatter of the environment,” she remembers. Some of the hospital personnel, who didn’t understand Dr. Jill’s condition and were insensitive to her vulnerability, tried to communicate by speaking louder and louder, as if she were hearing impaired, but this only upset and confused her more. What she needed was for those addressing her to speak slowly, pronounce clearly, and show a bit of compassion (Taylor, 2006). Fortunately, the neurologist overseeing her case was one of the few people who actually understood her condition. Dr. Anne Young looked into Dr. Jill’s eyes, spoke quietly, and touched her body with respect. “Although I could not completely understand her words, I completely understood her intention,” Dr. Jill recalls. “This woman understood that I was not stupid but that I was wounded”.

Concepts

On Day 2 in the hospital, Dr. Jill’s friend Steve told her that her mother, who went by the name of “G.G.,” would be coming to visit. Dr. Jill found the news perplexing (Taylor, 2006). What on Earth was a mother, and who or what was a G.G.? “Initially, I didn’t understand the significance of G.G.—as I had lost the concept of what a mother was,” she writes. The following day, G.G. appeared at the doorway, walked over to her daughter’s bed, and climbed in alongside her. As Dr. Jill recalls, “She immediately wrapped me up in her arms and I melted into the familiarity of her snuggle”.

Although the touch of G.G. felt familiar, the concept of her had slipped away, at least temporarily. Concepts are a central ingredient of cognitive activity, and are used in important processes such as memory, reasoning, and language (Slaney & Racine, 2011). Concepts are mental representations of categories of objects, situations, and ideas that belong together based on their central features or characteristics. The concept of superhero, for example, includes a variety of recognizable characteristics, such as: has supernatural powers, battles villains, protects innocent people, and wears unbecoming tights. Later we will demonstrate how the formation of these categories is dependent on experience, culture, and other factors. Abstract concepts (such as love, belonging, and honesty) are far more difficult to pinpoint than concrete concepts (like animals, furniture, and telephones). Personal experiences and culture shape the construction of abstract concepts, and we don’t always agree on their most important characteristics.

Without concepts, it would be quite difficult to understand the tidal wave of data flooding our brains every day. For example, we all know what dessert is. But if the concept dessert did not exist, we would have to describe all the characteristics that we expect of a dessert whenever one comes up in conversation: “Yesterday I ate the most delicious food—you know, those sweet-tasting, mouth-watering, high-calorie items typically consumed after lunch or dinner?” Thanks to our dessert concept, however, we can simply use the word “dessert” as shorthand for all of them. (“Yesterday I ate the most delicious dessert.”) And even if someone offers you a dessert with which you’re not familiar (for example, a chocolate tartelette), you still know that you are being offered a sweet food typically eaten after a meal.

Concepts allow us to organize and synthesize information, and to draw conclusions about specific objects, situations, and ideas that we have never encountered before. Imagine how exhausting thinking and talking would be if we did not have concepts to fall back on.

One way to understand concepts is to consider how they can be organized in hierarchies. Generally, psychologists use a three-level concept hierarchy to categorize information.

At the top of the hierarchy are superordinate concepts. This is the broadest category, encompassing all the objects belonging to a concept. The superordinate concept of furniture is depicted at the top of the hierarchy in Infographic 7.1. This is a very broad group, including everything from couches to nightstands.

Narrowing our focus to include only couches, we are considering the midlevel or basic level of our hierarchy. This is still a fairly general grouping, but not as broad as a superordinate concept such as furniture.

Subordinate-level concepts are even narrower, in this case referring to specific types or instances of couches, such as a loveseat, a La-Z-Boy, or my own couch with crumbs between the cushions.

Mouthwatering Concepts Which dessert do you prefer: the American sundae (right), the Turkish baklava (left), or the French tart (bottom)? You may not have tasted every one of these desserts, but you know they are sweet foods eaten after meals because you have developed a “dessert” concept.

left: Kailash K Soni/shutterstock.com; right: Shutterstock; bottom: Kheng Guan Toh/shuttterstock.com

The midlevel category is what we use most often to identify objects in everyday experience. Most children learn the midlevel (or “basic”) concepts first, followed by the superordinate and subordinate concepts (Mandler, 2008; Rosch, Mervis, Gray, Johnson, & Boyes-Braem, 1976). Although a child might grasp the meaning of couch, she may not understand furniture (the superordinate level) or chaise lounge (the subordinate level).

Reconstructing concept hierarchies was a formidable task for Dr. Jill, because so many of their layers had been washed away by the hemorrhage. But with hard work, relentless optimism, and the help of G.G., she slowly reconstructed concepts as diverse as alphabet letters and tuna salad. Using children’s books like The Puppy Who Wanted a Boy, G.G. helped her daughter retrain her brain to read, and by putting together puzzles, Dr. Jill was able to recreate concepts such as right side up and edge (Taylor, 2006). A trip to the laundromat became a lesson in first-grade math concepts—and the challenges involved in learning concepts all over again. Putting a few coins in her daughter’s hand, G.G. posed the following question: “What’s one plus one?” Perplexed, Dr. Jill came back with a more basic question: “What’s a one?”.

Now let’s take a look at the way concepts are formed. Formal concepts are created through rigid and logical rules (or “features” of a concept). When a child learns that 1 is an odd number because, like all other odd numbers, it cannot be divided evenly by 2 without a remainder, she is developing a simple formal concept. An object, idea, or situation must explicitly adhere to strict criteria in order to meet the definition of a particular formal concept. Science uses formal concepts to develop laws, theorems, and rules. Formal concepts introduced in this textbook include the pitch of a sound (defined by the frequency of the sound wave) and iconic memory (with a span of less than 1 second).

In contrast to formal concepts, natural concepts are defined by general characteristics and acquired during the course of our daily lives (Rosch, 1973). Identifying objects that fall into such categories is more difficult because their boundaries are imprecise and harder to define; natural concepts don’t have the same types of rigid rules for identification that formal concepts do (Hampton, 1998). This makes them more difficult to outline and therefore less useful in science.

Consider the natural concept of mother. Not everyone agrees what characteristics make a mother. Your concept of mother may be quite different from that of the person sitting next to you. What criteria do you use to determine if someone is a mother? Is it necessary for a person to get pregnant and have a baby? If so, the large group of women who adopt children are not included. What about someone who gives birth but then immediately puts the baby up for adoption—is she a mother?

In our daily use of natural concepts, we rely on prototypes, which are the ideal or most representative examples of natural concepts (Mervis & Rosch, 1981). Prototypes help us categorize or identify specific members of a concept. If you were asked to identify the ideal example of a mother, you might very well begin describing the characteristics of your own mother, because she is probably the mother with whom you are most familiar. If we asked you to name an example of a fruit, you would most likely say apple or orange—and not olive, unless, of course, you happen to be from Greece where olives are practically a staple. Infographic 7.1 presents a list of fruit organized from the most frequently suggested prototype (orange) to the least frequently suggested prototype (olive; Rosch & Mervis, 1975).

Remember, natural concepts evolve through life experience. Each person has a different journey and accumulates a unique collection of prototypes along the way. Dr. Jill’s mother G.G. was extremely patient and optimistic, perhaps contributing to Dr. Jill’s prototype of mother. Not all mothers have G.G.’s extraordinary patience and optimism, of course. Some have other characteristics, ranging from fierce loyalty to relentless pessimism. Think for a moment about the mothers who have touched your life, and how they have shaped your prototype of mother.

Items are easier to identify when they closely resemble prototypes. In the United States and Canada, the prototypes for the natural concept of fruit are commonly apples and oranges. If you were shown an image of a papaya (which may be very different from your prototype for a fruit), it would take you longer to identify it as belonging to the fruit category than if you were shown an image of a peach (which is more similar to the common prototypes). We suspect it would take you even longer to identify a durian or rambutan. Because natural concepts develop through daily experiences, prototypes vary from one person to the next. One study comparing adults in the United States and China found cross-cultural differences in the prototypical examples for mythological figures and tropical fish (Yoon et al., 2004).

We now know how the brain organizes information into meaningful categories, or concepts. But how is that information represented inside our heads, especially for concepts applying to people, places, and things not even present? With the help of mental imagery, another key ingredient of cognition, we see them in our mind’s eye and imagine how they look, sound, smell, taste, and feel.

Mental Imagery

Dr. Taylor’s stroke devastated certain aspects of her cognitive activity, such as language and memory. But some functions, like her ability to think visually, continued humming along quite smoothly. She had become hypersensitive to the subtle changes in people’s facial expressions and body language, and could understand the emotional content of their communication even when their words sounded all garbled (Taylor, 2006). If asked a question, she would search for answers in her arsenal of mental images. When a doctor quizzed her with the question, “Who is the president of the United States?”, Dr. Jill produced two pictures in her mind: one of a president and another of the United States. But when it came time to connect the dots—the president of the United States is Bill Clinton—she could not draw the line between the two facts. As Dr. Jill describes it, “Language with linear processing was out. But thinking in pictures was in”.

INFOGRAPHIC 7.1: Concepts and Prototypes

Concepts are used to organize information in a manner that helps us understand things even when we are encountering them for the first time. Formal concepts, like “circle,” allow us to categorize objects and ideas in a very precise way—something either meets the criteria to be included in that category, or it doesn’t. Natural concepts develop as a result of our everyday encounters, and vary according to our culture and individual experiences. We tend to use prototypes, ideal representations with features we associate most with a category, to identify natural concepts.

Credits: Vintage bed, Shutterstock; Two green olives, Shutterstock; Ripe pineapple, Shutterstock; Ripe orange, Shutterstock; Ripe banana, Shutterstock; Red apple, Shutterstock; Lemon, Shutterstock; Fresh tomato,Shutterstock; Fresh red strawberry, Shutterstock; Dried dates, Shutterstock; Coconut, Shutterstock; Black sofa, Shutterstock; Charpoy bedstead cot furniture, © Dinodia/age fotostock; 3D rendering of the canopy bed of Louis XV, Shutterstock; Red daybed, Thinkstock; Upholstered Sofa, Thinkstock

When people try to describe cognitive activity, they often provide descriptions of images from the “mind’s eye,” or mental images. Try to imagine, for instance, where your cell phone is right now. Did a picture of your beloved mobile device suddenly materialize in your head? If so, you have just created a mental image. Whether contemplating the whereabouts of cell phones or daydreaming about celebrities walking the red carpet, our brains are constantly whipping up vivid pictures. These mental images are not two-dimensional scenes frozen in time. Our brains have an amazing knack for manipulating them in three dimensions.

Let’s consider what we do when we examine a new object for the first time. We typically hold it in our hands (if it’s not too heavy) and rotate it to get a better sense of what we are looking at. If the object is too large to hold, we will often walk around it to see how it looks from various angles. Researchers are particularly interested in finding out if we mentally behave this way as well, and they have spent a great deal of time studying mental imagery and the rotation of objects.

In one of the earliest studies on this topic, Roger Shepard and Jacqueline Metzler (1971) had eight participants look at 1,600 pairs of object drawings like those displayed in Figure 7.1 and then asked them to mentally rotate one of the objects in the pair to determine if they were identical. In calculating the reaction times, the researchers discovered that the amount of time it took participants to rotate the object depended on the degree of difference between the orientations of the two objects. The greater the rotation, the longer it took participants to decide if the objects were identical.

FIGURE 7.1Manipulating Mental ImagesCan you tell which object pair is congruent? In order to figure this out, you must hold images of these figures in your mind and mentally manipulate them. (See bottom of column for answer.)

Source: Shepard and Metzler (1971).

This type of mental manipulation is extremely useful in your daily life. Remember, for example, the last time you tried to fit a large piece of furniture through a doorway, squeeze rolling luggage into the overhead bin of an airplane, or cram just one more container of leftovers into an overflowing refrigerator. In each case, you probably relied on some type of mental rotation to plan how to get each of these objects into or through a small space.

In another classic study, participants were instructed to study a map of a small fictional island (Figure 7.2). The researchers then asked them to close their eyes and imagine the map, first picturing one object (the hut) and then scanning across their mental image of the map until they “arrived” at a second object (the rock). The researchers found that it took longer for participants to “find” objects on the mental map when the objects were farther apart. As with the scanning of real objects, the amount of time it takes to scan a mental image is relative to the distances between the objects in the image (Kosslyn, Ball, & Reiser, 1978). Kosslyn (1978) also suggested that the size of the image is related to how much detail people can see in their mind’s eye. Fewer details can be detected on smaller images.

FIGURE 7.2Scanning Mental ImagesResearchers asked participants to imagine this fictional map and “find” objects there. As with a real object, it took longer to find objects that were farther apart.

Source: Kosslyn, Reiser, and Ball (1978).

Stop for a moment and imagine the smell of chocolate chip cookies baking in the oven, the tang of lemon on your tongue, or the sound of a cat meowing. It is important to remember that not all imagery is visual; other sensory experiences can be used to construct imagery in our minds. Reviewing research on auditory imagery, Hubbard (2010) concluded that auditory images are similar to true auditory stimuli (such as music and language) in their properties (for example, pitch and loudness), and that auditory images involve the brain areas used in auditory perception (like the right temporal lobe and Broca’s area). Interestingly, auditory imagery is associated with a person’s musical background and ability. When asked to think about two known song lyrics, study participants with musical training were better than other participants at identifying which of the songs would be sung at a higher pitch (Janata & Paroo, 2006).

We use mental images all the time—so often it’s hard to conceive of thinking without them. Imagine reading this chapter without being able to visualize Dr. Jill staggering around her house the morning of her stroke. How would your brain interpret the description of Steve’s voice sounding like a golden retriever if you could not “hear” the sound in your mind? Mental images, like concepts, lie at the heart of cognition.

Every cognitive activity we have discussed thus far, from establishing prototypes of fruit to mentally rotating leftovers in the refrigerator, is made possible by the electric and chemical bustle of millions of neurons. Let’s dive into that bustle and get acquainted with the biology of cognition.

Answer to Figure 7.1: a

Biology of Cognition

Dr. Jill’s story provides a stark illustration of the following principle: If the brain’s biological integrity is compromised, cognition is likely to suffer. The bleeding in her brain began in a small region on the left side of her cerebral cortex but soon spread across large areas of her brain (Taylor, 2006). Among the areas affected were her left frontal lobe, a part of the brain critical for a broad array of higher cognitive functions such as processing emotions, controlling impulses, and making plans. Remember that Dr. Jill experienced enormous difficulty devising a simple plan to save her own life (for example, she was unable to think of calling 911).

The stroke also ravaged brain regions critical for another major element of cognition: language processing. “As the blood interrupted the flow of information transmission between my two language centers (Broca’s anteriorly and Wernicke’s posteriorly)…. I could neither create/express language nor understand it,” Dr. Jill recalls in her book (Taylor, 2006, p. 62). Broca’s and Wernicke’s areas work with other parts of the brain to generate and understand language.

The biology of cognition can be found at the neural level as well. The torrent of blood passed through areas of Dr. Jill’s brain that were involved in memory and learning (Taylor, 2006). At some point in her life, she had surely learned that 911 is the number to call in a dire emergency, yet when it came time to retrieve that crucial information, her brain could not deliver. Normally, changes at the level of neurons make it possible to store and retrieve information. Apparently, the stroke had interfered with neurons involved in the retrieval of memories. It is also at the neuronal level where we see the amazing plasticity of the brain at work. Following a stroke, healing and regeneration begin with changes to neurons. These changes include greater excitability of the neurons, rewiring to take advantage of both hemispheres, increases in dendritic connections, and increased efficiency of connections at the synapses (Dobkin, 2005).

Reading Dr. Jill’s CT scans, the doctors were able to see the cause of all these cognitive malfunctions—an enormous hemorrhage on the left side of her brain: “It didn’t take someone with a Ph.D. in neuroanatomy to figure out that the huge white hole in the middle of the brain scan didn’t belong there!” (Taylor, 2006, p. 68).

Technologies such as CT are extremely useful for detecting abnormalities like strokes and tumors, but they also tell us a lot about normal cognitive functioning. Many interesting studies on cognition have investigated the biological basis of mental imagery. As it turns out, the brain often displays similar patterns of activity, whether we are imagining something or seeing it in real life.

In one study, researchers implanted electrodes in the brains of participants with severe epilepsy. This allowed the researchers to monitor individual neurons as participants looked at houses, animals, famous people, and other images. They found that some neurons responded to certain objects but not to others. A neuron would fire when the participant was looking at a picture of a baseball but not at an image of a face, for example. The researchers could identify the image the person was viewing simply by observing his brain activity. They also observed that the same neurons that became excited when the person was looking at an actual object also were active when the person was merely imagining that object (Kreiman, Koch, & Fried, 2000).

Using technology such as PET and fMRI, researchers have found that the visual cortex can be activated by mental imagery as well as by external stimuli (Ganis, Thompson, & Kosslyn, 2004). Information (from either an external stimulus or a mental image) is processed by the visual cortex, which works with other areas of the brain to identify images based on knowledge stored in memory. Researchers have noted that similar areas of the frontal and parietal regions of the brain are activated when study participants look at, for example, an image of a tree and when they imagine a tree. Once again, it appears that perception and imagery use many of the same neural mechanisms (Ganis et al., 2004).

We have now defined cognition, examined concepts and mental imagery, and explored their biological foundations. In the pages to come, we will learn about the more goal-oriented activities of problem solving and decision making. As you will learn, these processes can be fraught with difficulties.