Monday, February 21, 2011

(1983) Categorizing sounds and learning to read--a causal connection

(Bradley, L., & Bryant, P. E.) Prereaders were measured (N=368) for skills at sound categorization. These scores were related to progress in reading and spelling over a 4 yr. period. A subsample received intensive instruction in sound categorization and other forms of categorization. Group 1 sound only, Group 2 sound with alphabet letter, Group 3 conceptual categorization (animal, farm animal, etc.). 40 sessions over 2 yrs!

Results: Group 1 way ahead of group 3 by 3-4 mos. in standardized reading & spelling, suggesting a causal relationship. Group 2 succeeded better than 1 in reading and especially spelling, suggesting sound categorization is more effective when it involves explicit connection with a grapheme. Math test for all groups indicated few differences between them. ANCOVA established significant differences between groups in reading and spelling scores (p=.001) but not for math, with gr 2 surpassing 1 in spelling (p=.05).

Results indicate that PA prior to formal reading instruction has a powerful influence on the success in learning to read and spell. This study is the first with adequate empirical evidence that the link is causal. Hence, specific experiences which a child has before school may affect progress once formal instruction begins. Groups 1&2 consistently remained 3-4 months ahead of control groups.

Wednesday, February 16, 2011

(1990) Beginning to Read: Thinking and Learning About Print (Adams, M. J.)

Research on Pre-readers 
Letter Naming

  • Learning styles activities had no effect on reading (Bateman, 1979; Chall, 1978; Robinson, 1972; Williams, 1977). 
  • Letter naming was the best predictor of beginning reading (Bond & Dykstra, 1967; Chall, 1967).
  • Contradictory findings: Teaching to name letters no appreciable advantage (Gibson & Levin; 1975) Was it just a "symptom" instead of a cause?
  • Conclusion: Letter naming knowledge is a good predictor of success but just learning to name letters not enough.
      Explanation of predictive value of letters (p. 62).
  1. If you can name letters, quickly and accurately, indicated thorough knowledge of letters.
  2. Automaticity with naming allows the brain to focus elsewhere.
  3. Names of letters related to phoneme they represent; children can more easily relate the associated phoneme when they hear it in the name.
  4. Rapid letter naming, like other rapid identification (colors, shapes, numbers) indicates a capacity for visual recognition.
Phonemic Awareness
Second best predictor of first grade reading achievement was ability to discriminate between phonemes (Bond & Dykstra, 1967). 
We know phonemes well as adults and children. Repetition frees the mind from attention to the details, and concern for the process. There's no reason to pay attention to phonemes until we have to interpret them from a written text. Phoneme awareness tasks may not be understood by children, even if they are aware of phonemes. 

Decompose a syllable into its phonemes
Tapping task - tap for each phoneme. Performance on tapping task entering first grade correlated with reading achievement at the end of the year.
Study findings: Tapping task performance found to be causally related to decoding abilities an decoding abilities causally related to reading comprehension. Segmenting was insufficient. Explicit instruction in decoding scored significantly better than psycholinguistic group while both groups were equal on segmentation task (Tunmer & Nesdale, 1985, 1988).

Manipulation task
Delete or add phonemes: pill without /p/ = ill; add /s/ to top = stop 
Strong correlation between phoneme manipulation task and reading achievement, documented longitudinally through gr. 12 (Calfee, Lindamood, & Lindamood, 1973). Task too difficult for children before the end of first grade. Need well-developed spelling skills to delete, reorder, and insert. Rosner (1974) found after a year of instruction, there was little progress on learning the task.

Syllable splitting
Easier than segmentation or manipulation: break off first phoneme, pronounce it in isolation, say what is left: pink /p/ /ink/. Shown as a strong predictor of first grade reading achievement. 39% of the variance attributed to success at task (Share, Jorm, Maclean, & Matthews, 1984).

McNeil & Stone (1965) found children have less trouble analyzing nonsense syllables. Wallach & Wallach (1979) found low income poreschoolers can become proficient in splitting initial consonant sounds off. This, however, is a difficult task.  There's a strong relation to early reading achievement (Stanovich, Cunningham, & Freeman, 1984).

Blending Tasks
In blending, phonemes are provided rather than broken off. More difficult to hold on to unrelated sounds to blend than to say a meaningful word. Fox & Routh (1975) found only childrenwho could be coaxed to produce phonemes in isolation benefitted from blending training.  It was a strong predictor of reading achievement through gr. 4 (Chall, Roswell, & Blujmenthal, 1963). Strong predictor at gr. 1 (Lundberg, Olofsson, & Wall, 1980; Perfetti, Bell, & Hughes, 1987).

Oddity Tasks (easiest task)
Which word is different or doesn't belong (ala Sesame Street)? Basic compare & contrast tasks
Highly significant relationship between pre-k oddity task score and reading achievement in 3 yr follow-up (Bradley & Bryant, 1983). They selected 65 kids who performed poorly on the task.
Group 1 were provided 40 individual tutoring sessions comparing beg. mid. final sounds in words.
Group 2 were taught how sounds were represented by letters of the alphabet. (greatest gain here)
Group 3 categorized words semantically
Group 4 had no special training.

Nursery Rhyme knowledge (Most primitive level of PA)
Maclean, Bradley, and Bryant (1987) found early knowledge of nursery rhymes strongly and specifically related to development of more abstract phonological skills and of emergent reading abilities.

 ch 12: Phonological prerequisites: Becoming aware of spoken words, syllables and phonemes

Levels of Linguistic Awareness
My questions  - Do children need word awareness and syllable awareness before they acquire phoneme awareness? Isn't syllable awareness better used in constructing the orthography of words? Can't children develop word awareness as they are taught about phonemes? I would posit that they don't need to know the boundaries of a word in order to learn the phonemes within the word. Would scores on syllable awareness and/or word awareness predict phoneme awareness? Yet early phoneme awareness and letter recognition later predicts success in learning to read. PA is the essential building block. As the building is constructed, children begin to recognize the parts making the whole. Preschoolers love puzzles! Phonemes are another set of puzzle pieces to put together before you see the big picture - a meaningful word.

Monday, February 14, 2011

(2001) Phonemic awareness instruction helps children learn to read: Evidence from the National Reading Panel's meta-analysis

(Ehri, Nunes, Willows, Schuster, & Yaghoub-Zadeh, 2001) Meta-analysis of PA

Words of warning: "Well-designed experiments yielding positive outcomes provide the strongest evidence that PA caused the improvement in reading. Although all of the studies in our database consisted of experiments, some were better designed than others. Studies varied in whether they used treated or untreated control groups. The use of untreated controls receiving no special attention from researchers runs the risk of Hawthorne effects as an explanation for differences favoring the treatment group. Studies varied in whether students were randomly assigned to treatment and control groups, or whether a quasi-experimental design was used in which existing groups were assigned to conditions, or whether students were matched and assigned to conditions. Although random assignment is preferable, researchers may be limited to a quasi-experimental design when classrooms in schools are studied. We examined whether positive effects of PA instruction emerged primarily from the weaker designs or whether effects were strongest in the best designed experiments.”

* IMPORTANT IDEA: Preschoolers use language to communicate, focusing on meaning, not phonological structure. They have little PA and can gain much from PA instruction. Beginning readers have some phoneme  awareness, because making progress in reading requires grapheme-phoneme knowledge - taught in gr 1. PA instruction may contribute to literacy, but may be less effective than early PA instructions. Beyond first grade, PA may be less important than the need to learn spelling patterns in words, so instruction focused on phonemes could be purposeless. 

Quotes with potential (B&vI refers to Bus and van Ijzendoorn, 1999)
The "impact of PA instruction may be greatest in preschool and kindergarten, and may become smaller beyond first grade" (p. 255). In the B&vI (1999) meta-analysis, although all groups profited from PA instruction, preschoolers benefited more than kindergartners or primary school students.

"PA instruction may contribute less to older, normally developing readers, but may make a difference for older children who have failed to make normal progress in reading. Research has shown that disabled readers have poor phonemic awareness, even below that of nondisabled students reading at the same grade-equivalent level (Bradley, Bryant, 1983; Bruck, 1992; Fawcett and Nicholson, 1995). In addition, disabled readers have special difficulty learning to spell (Bruck, 1993). We might expect PA instruction to help in remediating the reading and spelling difficulties of these readers" (p. 255).

"Sounds are ephemeral, short-lived, and hard to grasp, whereas letters provide concrete, visible symbols for phonemes. Thus, we might expect children to have an easier time acquiring PA when they are given letters to manipulate. Also, because letters bring children closer to the task of applying PA in reading and spelling, we would expect transfer to be greater when PA is taught with letters. In the B&vI (1999) study, PA instruction with letters produced larger effects on PA and reading than instruction without letters" (p. 255).

Need to follow this model suggested in B&vI study
"B&vI (1999) obtained only partial support for this. They found that individualized instruction was less effective than small-group instruction for teaching PA, but was more effective for promoting transfer to reading. Replication of this effect with our larger database was considered important."

(1987) The nature of phonological processing and its causal role in the acquisition of reading skills

(Wagner & Torgesen, 1987) Reviews literature on Causal role of Phonological Processing in Reading acquisition, covering:
  • Introductory review of phonological nature of reading (definitions, assumptions about level of language conveyed by printed word
  • Relations between acquisition of reading skills and phonological awareness, phonological recoding for lexical access, phonetic recoding to maintain information in working memory.
  • Consider hypotheses about the nature of phonological processing that emerge from examining interrelations among measures of different kinds of phonological processing.
  • Summarize the major empirical findings from review, identify gaps in current knowledge and issues to be resolved, propose how gaps in current knowledge and unresolved issues can be addressed

Phone (Greek) sound or voice
Speech = continuously variable waves of acoustic energy, imperceivable
Phonetic level – speech represented by individual phones
Perceived sound distinctions are phonemes, that is, a group of phones that speakers of a language consider to be variations on the same sound.
Allophones are the individual phones that make up a phoneme.
Morphophoneme meaning & sound are components of our writing system and orthography.
Our knowledge about words is represented in our lexicons by abstract strings of systematic phonemes. Families of words are related by meaning
Speech = using phonological rules to transform abstract phonemes into surface phones that relate to the articulatory gesture of speech.
Syllable is the smallest independent articulable segment of speech, or a unit of speech segmentation. Vowels require vocal tract open and vocal folds vibrating.
Consonants produced by constricting vocal tract. Opening & closing of tract = syllable (but imprecise rather than easily distinguished)
Phonological processing is the use of oral information, that is, the sounds of our language for transcribing and interpreting written communication.

The nature of phonological processing

The alphabetic system provides information about our language at the phonological level. Without an awareness of the phonological component of our language, reading is a difficult process.

Acquiring Reading Skills (Older studies)

English spellings are not associated with meaning like pictographs might be, but with phonemes. Consequently, beginning readers need to know that printed symbols represent units of speech and units of speech are represented by phonemes (Crowder, 1982). Learning symbols (e.g., environmental print) can be accomplished by severely disabled readers (Rozin, Poritzky, & Sotsky, 1971), but learning printed symbols represent systematic phonemes (phonological nature of our language) is taxing.

Without PA, the pattern of letter-sound correspondences is arbitrary (Mattingly, 1980). It is necessary for both segmenting letter strings of words and blending sounds to pronounce the word (whether meaningful or not).

A 1974 study by Liberman, Shankweiler, Fisher, and Carter found 4 yr olds couldn’t segment words by phonemes but half of them could by syllable;17% of 5s could segment by phoneme, and half by syllable; 70% of 6s could segment by phoneme and 90% by syllable. Similar results were found in 1972 study by Calfee, Chapman and Venezky. 5½  yr olds could produce a rhyme 39% of the time. Success at producing early rhymes was correlated with later success in reading.

The nature of the task appears to be the key to whether young children can demonstrate phonological awareness.  Fox and Routh (1975) found evidence that PA can develop before reading is taught. 3-6 yr olds listened to monosyllabic words, and asked to say just a little bit of the word. 3s could segment some words into beginning and ending sounds. By 5, they could segment first & remaining sounds for half the words.

Bradley and Bryant (1985) used a phoneme categorization task with 4s and 5s (like Sesame St: One of these words doesn't belong; for initial, medial and final sounds). A follow-up three yrs later (N=368) correlations were found between performance on the original categorization task and performance on standardized achievement tests in reading, spelling, and a math test as well as the sound categorization delayed test and the WISC (1974 ed.). With IQ and age as constants, wound categorization accounted for 4-10% of the variance in rdg., 6-8% in spelling and 1-4% in math. Sound categorization score showed significance at p= .001, suggesting PA in prereaders is a causal factor in sucess in early reading and spelling. Size of the group makes the results reliable.

(2005) Learning to read words: Theory, findings, and issues

 (Ehri L. , 2005) Learning to read words
“Process of learning sight words involves forming connections between graphemes and phonemes to bond spellings of words to their pronunciations and meanings in memory. Enabled by phonemic awareness and by knowledge of the alphabet which functions as a powerful mnemonic to secure spellings in memory” (p. 167)

Visual-semantic connections lack sufficient mnemonic power. Don’t explain how the spellings of words are cabapble of encoding in memory with little practice. If meanings were anchors for words in memory we would expect synonomous readings (e.g., home for house).

Readers learn sight words by forming connections between letters in spellings and sounds in pronunciations of words FIND (Ehri, 1992, 1998). Formed from reader’s knowledge of grapheme-phoneme relations and phonemic awareness, knowing how to distinguish the separate phonemes in word pronunciation. Includes knowledge of spelling patterns that recur. In irregular words, most of the spelling is conventional. Knowledge of graphophonemic relations must be learned through explicit instruction or implicit learning and practice before bonding can occur. 

(2005) Descriptive-developmental performance of at-risk preschoolers on early literacy tasks. Reading Psychology

Justice, L. M., Invernizzi, M. A., Geller, K., Sullivan, A., & Welsch, J. (2005). Descriptive-developmental performance of at-risk preschoolers on early literacy tasks: Associations with age, race, and gender. Reading Psychology, 26, 1-25.

Large study of screening data from VA Early Reading Initiative (N=2161) 4 & 5 yr olds in at-risk preschool programs, indicating literacy deficits of preschoolers prior to entering Kindergarten.

Screening tests:
Written Language Awareness: Upper-case Alphabet Knowledge, Print Knowledge, Concept of Word, Name Writing;
Phonological Awareness: Rhyme, Beginning Sounds, Verbal Memory.

Findings: All seven screening tests were needed to account for variability in performance

Manova Results
·         Statistically significant difference among age levels (4yr N=1952; 5 yr N=209); age correlated with performance on written language awareness and phonological awareness tasks with the exception of verbal memory scores.
·         Both Af American (N=1166) & Caucasian children (N=891) performed better than Hispanic (N=131)
·         Girls outperformed boys on all tasks except for rhyme (small effect sizes on individual tasks – only .11 for beginning sounds)

Findings converge with many studies showing that preschool children display measurable levels of literacy skills in a variety of areas linked to later literacy achievement (p. 20).

“Empirically derived descriptions of early literacy achievements for children who are at risk is an important arena for research and practice given current national and local initiatives focused on prevention of reading difficulties in vulnerable populations” (p. 19).