How the Brain Learns to Read

by David A. Sousa

  So how is a beginning reader going to deal with differences in meaning that result from variations in syntax? The following six syntactic variations can be particularly troublesome and require some basic strategies that, by the way, do not always work (SLC, 2000):

  • Word order

  • Minimum-distance principle

  • Analysis of conjoined clauses

  • Passive voice

  • Negation

  • Embedding

  Word Order. As mentioned earlier, prereading children are accustomed to the subject-verb-object (SVO) sequence and rely heavily on it to decode early reading. This reliance is fine as long as the sentences are in the active voice, such as “He chased the dog.” Difficulties arise, however, when sentences are in the passive voice, such as “He was chased by the dog.” In the latter case, the order of the words, He, chased, and dog, is preserved, so the reader might misinterpret the sentence to mean “He chased the dog.”

  Minimum-Distance Principle. Because of the brain’s pattern-seeking predisposition, beginning readers assume that words in a sentence refer to the closest related words, verbs refer to the closest preceding nouns, and pronouns refer to the closest noun of the same gender. The minimum-distance principle is easily applicable to the sentence “He rowed the boat all by himself,” but not to “He rowed the boat that belonged to the fisherman all by himself.” Readers are apt to rely more on the minimum-distance principle when the number of words they have to remember in the sentence exceeds the capacity of their working memory.

  Analysis of Conjoined Clauses. While attempting to comprehend a sentence with two clauses, the young reader may assume that the two clauses are conjoined by a conjunction such as and. Consequently, the reader may misinterpret the sentence “The man chased the dog that ate the steak” to mean “The man chased the dog, and the man ate the steak.”

  Passive Voice. For the young reader, sentences containing the passive voice are particularly difficult to understand and learn. They violate the SVO sequence, and they can be particularly troublesome if they are reversible, such as “She was called by him,” which could be mistakenly read as “She called him.” Sometimes, common sense helps the reader to comprehend passive voice sentences correctly. For example, in the sentence “The window was broken by the baseball,” it is clear that the window couldn’t break the baseball, so only one interpretation makes sense.

  Negation. Sentences written in the negative are usually more difficult for the young brain to comprehend. That is because the brain tends to first interpret the sentence in the positive sense, and then move to the second phase to process the negative sense. Consequently, the young reader will find the sentence “Circle the picture that shows cows and sheep” easier to understand than “Circle the picture that has cows but not sheep.” Substantial practice with negation can improve a reader’s comprehension and fluency with these types of sentences.

  Embedding. Embedded clauses can lead to ambiguity or misinterpretation. In Grades 2 and 3, readers encounter the following three types of embedded clauses:

  1. The subject of the main clause is the same as the subject of the embedded clause. Example: “The boy rowed the boat and waved to his mother.” These are usually easy for young readers to understand.

  2. The object of the main clause is the subject of the embedded clause. Example: “The man chased the dog that ate the steak.” These are more difficult to comprehend accurately. The reader may incorrectly apply the conjoined-clause strategy here and read the sentence as “The man chased the dog, and the man ate the steak.”

  3. The subject of the main clause is the object of the embedded clause. Example: “The boat that the boy rowed belongs to the fisherman.” Ambiguity arises because these types of sentences violate both the SVO sequence and the minimum-distance principle.

  As students read more and as their working memory becomes more efficient, they gradually switch from using these rudimentary strategies to paying closer heed to the actual syntax of sentences.

  Morphology and Comprehension

  Morphology, you will recall, studies how words are put together from pieces (e.g., prefixes and suffixes), and how these pieces can change the meaning of words or create new ones. Morphological awareness contributes to reading comprehension in the following ways (Mahony et al., 2000):

  • Meaning. The reader is able to distinguish the difference between nouns formed by adding -tion and nouns formed by adding -ive. Thus, operation and operative are formed from the same root word but have different meanings.

  • Syntactic properties. The reader understands that a particular suffix indicates a part of speech. For example, -y indicates an adjective (noisy) and -ly indicates an adverb (noisily).

  • Phonological properties. The reader understands that derivational suffixes can alter the pronunciation of the root word. For example, adding -ic to hero involves a shift in emphasis from the first syllable of heroic to the second, and adding -al to hymn involves pronouncing the previously silent consonant -n in hymnal.

  • Relational properties. The reader understands the relationship between words formed by adding different prefixes and suffixes to the same root word, as in import and export or in operation and operative. When readers use relational properties effectively, their reading fluency, pronunciation, and comprehension improve. Furthermore, they get better at distinguishing between true morphological relationships, such as sail-sailor, and false ones, such as may-mayor.

  Decoding Ability, Intelligence, and Comprehension

  Research studies have shown that phonological awareness, phonological memory, and visual-spatial skills (all part of decoding) are stronger predicators of success with reading comprehension than intelligence during the stages of early reading (Brunswick, Martin, & Rippon, 2012). As children progress, however, the research evidence suggests that decoding speed as well as intelligence (as measured by standard IQ tests) are closely related to reading comprehension. One study involving 124 children found that decoding ability was the best single predictor of how well the child comprehended the reading. The child’s IQ was also a significant predictor, although not as strong as decoding ability (Tiu, Thompson, & Lewis, 2003).

  Reading Comprehension and Language Comprehension

  Not surprisingly, reading comprehension is very closely related to spoken language comprehension. It reflects the degree of coordination between the brain’s language processing and visual recognition systems. If that is the case, how do we explain those children who can read words but whose comprehension in reading is not as good as their spoken language comprehension? One likely explanation is that children learn spoken language in settings that are different from where they learn to read. Written language generally adheres to stricter grammatical structures and uses more formal vocabulary than spoken language. Consequently, how well a child comprehends a written text is determined by how well that child comprehends the same text when it is spoken.

  HOW MEMORY AFFECTS LEARNING TO READ

  To understand how memory affects reading, we need a brief review of the brain’s memory components. As researchers gain greater insight into the brain’s memory processes, they have had to devise and revise terms that describe the various stages of memory. Neuroscientists now believe that we have two temporary memories that perform different tasks. It is a way of explaining how the brain deals briefly with some data, but can continue to process other data for extended periods of time. For now, short-term memory is used by cognitive neuroscientists to include the two stages of temporary memory: immediate memory and working memory (Gathercole, 2008). Figure 2.2 illustrates the stages of temporary and permanent memory.

  Immediate Memory

  Immediate memory is one of the two temporary memories and is represented in Figure 2.2 by a clipboard, a place where we put information briefly until we make a decision on how to dispose of it. Immediate memory operates subconsciously or consciously and holds data for up to about 30 seconds. (Note: The numbers used in t
his chapter are averages over time. There are always exceptions to these values as a result of human variations or pathologies.) The individual’s experiences determine its importance. If the information is of little or no importance within this time frame, it drops out of the memory system. For example, when you look up the telephone number of the local pizza parlor, you usually can remember it just long enough to make the call. After that, the number is of no further importance and drops out of immediate memory. The next time you call, you will have to look up the number again.

  Working Memory

  Suppose, on the other hand, you can’t decide whether to call the pizza parlor or the Chinese takeout place, and you discuss these options with someone else in the room. This situation requires more of your attention and is shifted into working memory for further processing. Working memory is the second temporary memory and the place where conscious, rather than subconscious, processing occurs. In Figure 2.2, working memory is shown as a work table, a place of limited capacity where we can build, take apart, or rework ideas for eventual storage somewhere else. When something is in working memory, it generally captures our focus and demands our attention. Scanning experiments show that most of working memory’s activity occurs in the frontal lobes, although other parts of the brain are often called into action (Gathercole, 2008; Goldberg, 2001).

  Capacity of Working Memory

  Working memory can handle only a few items at one time. This functional capacity changes with age. Preschool infants can deal with about two items of information at once. Preadolescents can handle three to seven items, with an average of five. Through adolescence, further cognitive expansion occurs, and the capacity increases to a range of five to nine, with an average of seven. For most people, that number remains constant throughout life.

  Figure 2.2 This diagram illustrates the theory of temporary and permanent memories. Information gathered from our senses lasts only a few seconds in immediate memory. Information that needs further processing moves to working memory where it usually endures for minutes or hours, but can be retained for days or longer, if necessary. The long-term storage sites (also called permanent memory) store information for years.

  This limited capacity explains why we have to memorize a song or a poem in stages. We start with the first group of lines by repeating them frequently (a process called rehearsal). Then we memorize the next lines and repeat them with the first group, and so on. It is possible to increase the number of items within the functional capacity of working memory through a process called chunking. In spoken language, chunking occurs when the young child’s mind begins to combine phonemes into words, such as when can and dee become candy.

  Time Limits of Working Memory

  Working memory is temporary and can deal with items for only a limited time. For preadolescents, it is more likely to be 5 to 10 minutes, and for adolescents and adults, 10 to 20 minutes. These are average times, and it is important to understand what the numbers mean. An adolescent (or adult) normally can process an item in working memory intently for 10 to 20 minutes before fatigue or boredom with that item occurs and the individual’s focus drifts to other items. For focus to continue, there must be some change in the way the individual is dealing with the item. As an example, the person may switch from thinking about it to physically using it, or making different connections to other learnings. If something else is not done with the item, it is likely to fade from working memory.

  This is not to say that some items cannot remain in working memory for hours, or perhaps days. Sometimes, we have an item that remains unresolved—a question whose answer we seek or a troublesome family or work decision that must be made. These items can remain in working memory, continually commanding some attention, and can, if of sufficient importance, interfere with our accurate processing of other information. Eventually, we solve the problem, and it clears out of working memory.

  Reading Comprehension and Working Memory

  Spoken language uses memory systems for meaning. Memory helps students remember a set of oral directions: “Take out your math book and do the even-numbered problems on pages 18 and 19, and then check your answers on page 237.” But reading is a far more complicated skill involving a number of brain systems. When reading a word, the decoding process breaks the word into its segments, and while being retained in working memory, the phonemes are blended to form words that the reader can recognize. The ability to retain verbal bits of information is referred to as phonologic memory.

  When reading sentences, the visual and memory systems of the brain must decode and then retain the words at the beginning of a sentence for a period of time while the reader’s eyes move to the end of the sentence. In a short sentence like “See the dog run,” that is no problem because the memory time-span requirement is minimal. However, reading complex sentences, such as “The boy ran down the street to tell his friend that the ice cream truck was just around the corner and would be here soon,” requires much more memory time. Furthermore, the brain must pay attention to syntax and context in order for the sentence to be accurately understood. Because of working memory’s limited capacity, beginning readers will have difficulty understanding long sentences or sentences with complex structure or syntax. They may be able to read the sentence aloud, but may not comprehend its meaning (Figure 2.3).

  A child’s ability to store words temporarily in working memory depends on several factors, such as age, experience, and language proficiency. But the code that readers of any age use to store written words and phrases is a phonological code. Consequently, phonological coding skills are crucial for using and developing the ability of working memory to store representations of written words. A reader with efficient phonological decoding skills will be able to quickly generate and retain phonetic representations of written words as well as preserve the words themselves and their sequence in the sentence. By developing these working memory skills, the reader with appropriate background knowledge can comprehend not only the sentence, but also the paragraph and the chapter.

  During reading, working memory helps comprehension in the following two ways:

  • Understanding complex structure. In complex sentences, such as “The woman who is getting into the blue car dropped her key,” working memory holds the decoded results of the first part of a sentence while the visual cortex processes the words and phrases in the rest of the sentence. Working memory then puts all the pieces together to establish the sentence’s meaning.

  Figure 2.3 As a young beginning reader’s eye moves across the sentence, words that were at the beginning may fade from working memory. By the time the eyes gets toward the end of the sentence, the reader may not remember the previous words and thus cannot establish meaning.

  • Preserving syntax (word order). Take the sentence “The driver of the blue car, not the red car, honked his horn.” Here, working memory preserves the word order so that the reader can process the sequence, recognize negation, and correctly identify who honked the horn.

  As reading progresses, the meaning of each sentence in a paragraph must be held in memory so that the sentences can be associated with each other to determine the intent of the paragraph and whether certain details need to be remembered. Working memory must then link paragraphs to each other so that, by the end of the chapter, the reader has an understanding of the main ideas encountered. With extensive practice, the working memory becomes more efficient at recognizing words and at chunking words into common phrases. As a result, the child reads faster and comprehends more.

  Forming Gists

  Because working memory has a limited capacity, it cannot hold all the words of a long sentence. To deal with this limitation, working memory merges words within a clause to form a gist (the memory device known as chunking) that is then temporarily stored in place of the words. A gist essentially preserves a mental summary of the event described in what the individual just read, without the exact words (or number or pictures, for that matter). As reading continues, the bra
in adds new gists of clauses until the sentence is completed. Then a gist of the sentence is generated. Gists from other sentences in the paragraph are chunked to form a higher-level gist of the paragraph. Then, gists of paragraphs are chunked to form an even higher-level gist of the chapter, and eventually for the entire text. Table 2.3 shows how gists at one level combine to form gists of the next level.

  Early reading makes heavy demands on both the processing and storage functions of a young working memory. Chunking the representations of word forms into gists is an efficient way of managing the competition for space and time in working memory. Gists take up less space and are retained while individual word forms are deleted. Sentence gists are then deleted when paragraph gists are formed, and so on. Clause gists endure for about 30 seconds; chapter gists can last for 15 minutes or more (SLC, 2000). However, these endurance times can be extended through oral rehearsal and with written summaries when the child is able to write. Gists can remain in memory networks for extended periods and serve as cues for recall. We have all had the experience where an unexpected stimulus (e.g., an old song or the odor of a perfume) brings back a memory or an event that may have occurred years ago. We cannot quite remember the details, but the “gist” is there (Reyna et al., 2011).

  Table 2.3 Levels of Reading Comprehension Gists in Working Memory

  SOURCE: SLC (2000).

  Other factors affect the ability of working memory to retain or lose information during reading (Figure 2.4). New reading that the child finds interesting is likely to make it past immediate memory to working memory for conscious processing. And if the new reading activates material recently learned, long-term storage retrieves that information and moves it into working memory where it enhances the acquisition of the new learning. This process is called transfer and represents one of the most powerful principles of learning (Sousa, 2011a).