Preferring alphabet–keyboard compatibility: Congruency between spatial codes shapes the affective connotation of letters

When letters are encountered, two spatial stimulus codes resulting from their positions within the alphabet and on the computer keyboard are activated mentally. If these two spatial codes match, letter processing is more efficient. The present study tested whether the processing fluency gain resulting from alphabet–keyboard compatibility also enhances affective evaluations of letters. In Experiment 1, participants preferred alphabet–keyboard compatible over incompatible letters in a forced-choice preference rating. Similarly, in Experiment 2, liking ratings for alphabet–keyboard compatible letters were higher compared to incompatible letters. Moreover, in Experiment 3, preference ratings of non-words were positively correlated with the relative number of alphabet–keyboard compatible letters within these letter strings. These findings suggest that alphabet–keyboard compatibility shapes the affective connotation of letters. Moreover, this processing fluency–valence association is activated at the level of letters as well as whole letter strings.     

Are individual or consecutive letters the unit affected by repetition blindness?

When 2 similar words (e.g., react reach) are briefly sequentially displayed, the 2nd word may be omitted from the report, a phenomenon known as repetition blindness (RB). Previous researchers have suggested that consecutive letters are the unit affected by RB. Six experiments provided new data on orthographic RB. Two letters at the beginning or end of words resulted in RB, as did alternating interior letters (tactile earthly) and 3 letters with different relative positions (arid bird). However, no RB was found with a single final letter (show view). Observed RB may reflect pattern completion because RB for pairs like throat theory was reduced when the nonrepeated letters (eory) were consistent with only a single word. The experiments point to a model of orthographic RB in which both individual letters and letter sequences of length 2 or more play a role.     

The memorial structure of organized sequences

Subjects were asked to memorize a sequence of nine consonants which were grouped into three groups of three letters each (e.g., SBJ FQL ZNG). After learning the sequence, they were presented with single letters, letter pairs, or letter triples and asked to indicate if the probe item appeared in the memorized sequence. The latency results suggest that subjects engage in a linear self-terminating memory search in which the items from one chunk are retrieved from memory as the items from the immediately preceding chunk are being scanned. When the probe consisted of more than one item, the subjects were slowed in their comparison if the letters came from different chunks (e.g., JF vs. FQ in the above illustration), and the number of letters in the probe also influenced the reaction time. Neither of those effects were obtained if all the letters in the probe came from the same chunk, and that would seem to suggest that the probe items from the same chunk were compared in parallel to the letters in the memory item, while items from different chunks were compared serial.     

Effects of noise letters on decisions: Discrete or continuous flow of information?

Four forced-choice letter-detection experiments examined the effect on detection latency of noise letters that were visually similar to target letters. A single target letter was present in each display. Noise letters were similar to the target letter present in the display (the signal), to a different target letter assigned to the same response as the signal, or to a target letter assigned to the opposite response from the signal. Noise letters were present in either relevant or irrelevant display positions, and two quite different stimulus sets were used. The experiments were designed to test a prediction of models in which information about noise letters is transmitted continuously from the recognition to the decision process. These models predict that responses should be faster when noise letters are visually similar to a target assigned to the same response as the signal than when noise letters are similar to a target assigned to the opposite response. Statistically reliable effects of the type predicted by continuous models were obtained when noise letters appeared in relevant display positions, but not when they appeared in irrelevant positions.     

A study of relative-position priming with superset primes

Four lexical decision experiments are reported that use the masked priming paradigm to study the role of letter position information in orthographic processing. In Experiments 1 and 2, superset primes, formed by repetition of 1 or 2 letters of the target (e.g., jusstice-JUSTICE) or by insertion of 1 or 2 unrelated letters (e.g., juastice-JUSTICE), generated significant priming compared with unrelated primes and did not differ significantly from an identity priming condition. In Experiment 3, identity primes generated significantly faster responses than subset primes formed by removal of 2 letters from the target (e.g., jutie-JUSTICE), and subset primes generated faster responses than substitution primes formed by substitution of 2 letters of the target with unrelated letters (e.g., jumlice-JUSTICE). In Experiment 4, insertion of 3 unrelated letters continued to generate facilitation relative to unrelated primes but significantly less so than the identity prime condition. The authors discuss the implications of these results for letter-position coding schemes.     

Covert reading of letters in a case of global alexia

This study describes the case of a global alexic patient with a severe reading deficit affecting words, letters and Arabic numbers, following a left posterior lesion. The patient (VA) could not match spoken letters to their graphic form. A preserved ability to recognize shape and canonical orientation of letters indicates intact access to the representation of letters and numbers as visual objects. A relatively preserved ability to match lowercase to uppercase letters suggests partially spared access to abstract letter identities independently of their visual forms. The patient was also unable to match spoken letters and numbers to their visual form, indicating that she could not access the graphemic representations of letters from their phonological representations. This pattern of performance suggests that the link between graphemic and phonological representations is disrupted in this patient. We hypothesize that VA’ residual reading abilities are supported by the right hemisphere.     

Language habits and detection in very short-term memory

Target letters in briefly presented word displays are known to be better detected than when they are presented in anagram arrangements of the words’ letters. Target detection may have been higher for word displays either because Ss identified the words and then determined if a word possessed the target or because, in word displays, Ss could anticipate letters from the transitional probabilities (TRP) of letters in the language (TRP hypothesis). Detection in Experiment I was identical for words and for pseudowords, stimuli which were meaningless rearrangements of the words’ letters but which presented the words’ level of interletter TRP. Randomly rearranged displays, with lower TRP values, yielded lower detection rates. Experiment II showed that detection increased with TRP levels in nonword displays. The results support the TRP hypothesis and thus are consistent with a serial-scanning process in very short-term memory, but are also consistent with a special variant of a parallel process.     

Competing top-down processes in visual selection: evidence that selection by location is stronger than selection by color

The purpose of this study was to examine whether color and position information are functionally equivalent when observers are asked to select simultaneously on both dimensions. Observers were asked to report a letter of a given color from a given region of a briefly flashed letter array, then to report any additional letters they could recall from the stimulus set. Of the additional letters, more location letters were reported than were same-color or neutral letters. The results suggested that position information has priority over color information in top-down-guided visual selection.     

Difficulty and familiarity norms for 192 single-solution word fragments

Normative data are presented for the probability of successfully completing 192 single-solution word fragments. Normative data on the familiarity of college students with the solution words are also given, along with estimates of word frequency from existing norms. Regression analyses were performed in order to predict fragment completion difficulty from familiarity, frequency, and several structural characteristics of the fragments. Familiarity, whether or not first and/or last letters appeared in the fragment, and the ratio of letters to missing letters in the fragment were included in the regression equation as significant predictors of difficulty for this fragment set.     

Temporal limits of selection and memory encoding: A comparison of whole versus partial report in rapid serial visual presentation

People often fail to recall the second of two visual targets presented within 500 ms in rapid serial visual presentation (RSVP). This effect is called the attentional blink. One explanation of the attentional blink is that processes involved in encoding the first target into memory are slow and capacity limited. Here, however, we show that the attentional blink should be ascribed to attentional selection, not consolidation of the first target. Rapid sequences of six letters were presented, and observers had to report either all the letters (whole-report condition) or a subset of the letters (partial-report condition). Selection in partial report was based on color (e.g., report the two red letters) or identity (i.e., report all letters from a particular letter onward). In both cases, recall of letters presented shortly after the first selected letter was impaired, whereas recall of the corresponding letters was relatively accurate with whole report.     

The salience of silent letters in children’s memory for word spellings

To compare children’s memory for silent and pronounced letters in familiar spellings of words, 7- to 10-year-olds were given two tasks. First, they imagined word spellings and decided whether target letters were present. Then they recalled the words associated with the target letters. Five experiments yielded similar findings. Pronounced letters were recognized somewhat more accurately than silent letters. However, silent letters were detected more rapidly in words than pronounced letters were, and silent letters prompted superior recall of words. The influence of several factors, such as the particular words chosen, the position of letters, and the expectancies of subjects, was ruled out in one or another experiment. Two explanations for findings are proposed. The favorite is that effects reflect the way silent letters are stored in long-term memory when spellings are learned. The other is that events occurring in the experiment enhanced episodic memory for silent letters.     

Sex differences in retention of verbal and spatial characteristics of stimuli

Males and females from Grades 3, 6, and college viewed sets of five or seven letters in a 4 × 4 matrix, and remembered either (a) names of the letters, (b) positions of the letters within the matrix, or (c) both letters and positions. At all grade levels females remembered letters more accurately than positions, while males remembered letters and positions equally well. However, there was also evidence that verbal and spatial information was processed independently by both males and females. Results are discussed in terms of neurological development and sex differences in specific abilities.     

Orthographic repetition blindness

Repetition blindness (RB) is the failure to report the second occurrence of a repeated word, when words are sequentially and briefly displayed (Kanwisher, 1987). RBis also observed for non-identical words, such as home, dome . Explanations for non-identity RB assume that similarity at the level of the whole word causes the secondword to be suppressed ('similarity inhibition'). Three experiments demonstrate that RB is robust for diverse types of orthographic relatedness, including critical words that share only their first initial letter, their last two letters, first three letters, middle three letters, beginning and final letters, three alternating letters, and three non-aligned letters (as in chance hand ). The theoretical construct of similarity inhibition may be able to account for these data, although one mechanism previously proposed in the literature, neighbourhood inhibition, is probably not a useful way to explain the data on RB for words sharing only one or two letters. Weintroduce an alternative explanation for orthographic RB: Only the repeated letters are suppressed, and amount of RB depends on howeasily the perceiver can reconstruct the target word from the non-suppressed letters.     

Case-sensitive letter and bigram frequency counts from large-scale English corpora.

We tabulated upper- and lowercase letter frequency using several large-scale English corpora (approximately 183 million words in total). The results indicate that the relative frequencies for upper- and lowercase letters are not equivalent. We report a letter-naming experiment in which uppercase frequency predicted response time to uppercase letters better than did lowercase frequency. Tables of case-sensitive letter and bigram frequency are provided, including common nonalphabetic characters. Because subjects are sensitive to frequency relationships among letters, we recommend that experimenters use case-sensitive counts when constructing stimuli from letters.     

Phonological false recognition produced by bottom-up automatic activation in young and older people

ABSTRACT

Two experiments explored a new procedure to implicitly induce phonological false memories in young and older people. On the study tasks, half of the words were formed from half of the letters in the alphabet, whereas the remaining words were formed from all the letters in the alphabet. On the recognition tests, there were three types of non-studied new words: critical lures formed from the same half of the letters as the studied words; distractors formed from the other half of the letters not used, and distractors formed from all the letters in the alphabet. In both experiments, the results showed that, in both young and older people, critical lures produced more false recognitions than distractors composed of all the letters in the alphabet, which, in turn, produced more false alarms than distractors composed of the letters not used during the study. These results support the predictions of the activation/monitoring models, which assume that false memories are partly due to activation spreading from items (semantically or phonologically) related to the critical words.     

Case-sensitive letter and bigram frequency counts from large-scale English corpora

We tabulated upper- and lowercase letter frequency using several large-scale English corpora (∼183 million words in total). The results indicate that the relative frequencies for upper- and lowercase letters are not equivalent. We report a letter-naming experiment in which uppercase frequency predicted response time to uppercase letters better than did lowercase frequency. Tables of case-sensitive letter and bigram frequency are provided, including common nonalphabetic characters. Because subjects are sensitive to frequency relationships among letters, we recommend that experimenters use case-sensitive counts when constructing stimuli from letters.     

Naming and locating simultaneously and sequentially presented letters

Two letters varying in level of confusability were presented either simultaneously for 75 msec or sequentially for 75 msec each in adjacent retinal locations. The retinal locus of presentation varied from trial to trial, and subjects both identified and located the presented letters. Identification accuracy was higher on nonconfusable than on confusable letter pairs in the simultaneous condition, but not in the sequential condition. This result is interpreted as support for the notion that inhibition between similar or identical features shared by confusable letters occurs only when letters are presented simultaneously. A relative position effect, with performance on the peripheral letter higher than on the central letter, was found for simultaneously and second sequentially presented letters, but not for first sequentially presented letters. This result is interpreted in terms of the assumption that feature perturbations, with foveal perturbations more likely than peripheral perturbations, affect simultaneously and secondpresented letters, but not first-presented letters. The pattern of results for relative location accuracy showed many of the same effects as identification performance. A model assuming location errors reflect feature transpositions is outlined and is able to account for the absolute and relative location results and the correlation between relative location and identification accuracy.     

Attention and information storage in visual short-term memory

Schioldborg, P. Attention and information storage in visual short-term memory. Scand. J. Psychol., 1973, 14, 1–3.- Information retrieval from STM was examined with Sperling's (1960) method. Of nine letters displayed in rows of three, the number of letters correctly reported from each row differed significantly, the mean being 2.4, 2.2, and 1.6 letters for the middle, upper, and lower row, respectively. By increasing exposure time, number of correctly reported letters increased for each row at equal rate. However, by increasing the delay period of the selection signal, number of letters decreased at different rates, the reduction being 48%, 24%, and 10% for the lower, upper, and middle row respectively. The results are assumed to reflect differences in the initial attention level for the individual item; the smaller this level, the lower the level of information processing and the faster the erasure from STM.     

New evidence for the perceptual precedence of global information

Two experiments are reported investigating the order in which global and local information of visual forms is processed. Subjects were presented with compound stimuli and were asked to identify the local level, always consisting of small letters. At the global level, the stimuli could be either large letters, consistent or inconsistent with the local level, or meaningless patterns derived from the large letters by modifying the spatial relations among segments. Results showed that inconsistent stimuli were responded to more slowly than both consistent stimuli and meaningless patterns, which did not differ from each other. This was true both when letters and patterns were presented intermixed, as in experiment 1 or separately, as in experiment 2. The pattern obtained accords well with predictions derived from the perceptual precedence hypothesis which states that global information becomes available at a faster rate than local information. No support for the alternative, post-perceptual, hypothesis was found.     

The word-detection effect: Sophisticated guessing or perceptual enhancement?

Subjects discriminate letters in words better than letters in nonwords. The sophisticated guessing hypothesis attributes this word advantage to a guessing strategy. In words, the possible letters at each letter position are constrained by letters at other positions, whereas letters in nonwords are not restricted in this manner. A critical test of this hypothesis is that if subjects are givenexplicit knowledge of the letters in nonwords before the trial, the word advantage would disappear. We investigated the effect of preknowledge of the alternatives in the word-detection effect. In the word-detection effect, subjects decide which of two character strings contains letters and which contains pseudoletters. In four experiments, subjects were more accurate with words than with nonwords, and subjects were more accurate when they were told the word or nonword before the trial. However, even with foreknowledge of the alternatives, subjects were more accurate with words than with nonwords.