The effects of frequency, repetition and stimulus quality in visual word recognition

This paper describes a lexical decision experiment, which examined the relation between word frequency, repetition and stimulus quality. In contrast to earlier studies (Stanners, Jastrzembski and Westbrook, 1975; Becker and Killion, 1977), frequency and stimulus quality were found to interact. The implications of this result for models of word recognition are discussed within the framework of Becker's verification model.     

Exploring the additive effects of stimulus quality and word frequency: The influence of local and list-wide prime relatedness

Stimulus quality and word frequency produce additive effects in lexical decision performance, whereas the semantic priming effect interacts with both stimulus quality and word frequency effects. This pattern places important constraints on models of visual word recognition. In Experiment 1, all three variables were investigated within a single speeded pronunciation study. The results indicated that the joint effects of stimulus quality and word frequency were dependent upon prime relatedness. In particular, an additive effect of stimulus quality and word frequency was found after related primes, and an interactive effect was found after unrelated primes. It was hypothesized that this pattern reflects an adaptive reliance on related prime information within the experimental context. In Experiment 2, related primes were eliminated from the list, and the interactive effects of stimulus quality and word frequency found following unrelated primes in Experiment 1 reverted to additive effects for the same unrelated prime conditions. The results are supportive of a flexible lexical processor that adapts to both local prime information and global list-wide context.     

The role of bigram frequency in the perception of words and nonwords

Memory & Cognition - Adult subjects decided whether strings of four, five, or six letters formed words or nonwords. Words and nonwords were equally probable stimuli, and there were equal...     

The effects of stimulus set size and word frequency on verbal serial recall

Two experiments are reported which examine immediate serial recall for high-and low-frequency words. The words in each list were either repeatedly drawn from the same small pool of candidates (in the closed set conditions) or each word only ever occurred once during the experiment (in the open set conditions). The results consistently show an effect of word frequency but the effect of set size was only apparent for low-frequency words. It is argued that both frequency and set size effects reflect processes concerning the “clean-up” of degraded short-term memory traces.     

The effects of stimulus set size and word frequency on verbal serial recall

Two experiments are reported which examine immediate serial recall for high- and low-frequency words. The words in each list were either repeatedly drawn from the same small pool of candidates (in the closed set conditions) or each word only ever occurred once during the experiment (in the open set conditions). The results consistently show an effect of word frequency but the effect of set size was only apparent for low-frequency words. It is argued that both frequency and set size effects reflect processes concerning the "clean-up" of degraded short-term memory traces.     

Immediate and delayed effects of word frequency and word length on eye movements in reading: a reversed delayed effect of word length

Three experiments examined the effects in sentence reading of varying the frequency and length of an adjective on (a) fixations on the adjective and (b) fixations on the following noun. The gaze duration on the adjective was longer for low frequency than for high frequency adjectives and longer for long adjectives than for short adjectives. This contrasted with the spillover effects: Gaze durations on the noun were longer when adjectives were low frequency but were actually shorter when the adjectives were long. The latter effect, which seems anomalous, can be explained by three mechanisms: (a) Fixations on the noun are less optimal after short adjectives because of less optimal targeting; (b) shorter adjectives are more difficult to process because they have more neighbors; and (c) prior fixations before skips are less advantageous places to extract parafoveal information. The viability of these hypotheses as explanations of this reverse length effect on the noun was examined in simulations using an updated version of the E-Z Reader model (A. Pollatsek, K. Reichle, & E. D. Rayner, 2006c; E. D. Reichle, A. Pollatsek, D. L. Fisher, & K. Rayner, 1998).     

Recognition of affixed words and the word frequency effect

Three experiments are reported in which the word frequency effect is used as a diagnostic for determining whether affixed words coming from the same stem are stored together or separately in the lexicon. Prefixed words are examined in the first experiment, inflected words in the second and third. In the first two experiments, two types of word are compared where the words in each condition are matched on surface or presented frequency but are varied on the frequency of their stems or base frequency. It is found that lexical decision times are influenced by base frequency, thus indicating that words related by affixation are stored together in the lexicon. The third experiment, however, demonstrates that when base frequency is held constant and surface frequency is varied, lexical decision times are influenced by surface frequency. The results are accounted for by a model of word recognition whereby frequency has its effect at two different stages of the recognition process.     

中文阅读预视加工中的词频和预测性效应及其对词切分的启示:基于眼动的证据

研究采用眼动随动显示技术考察中文阅读预视加工中的词汇加工问题。前三项实验发现,剥夺预视加工的掩蔽条件、正确提示词n+1右侧边界的掩蔽条件以及不能提示词n+1右侧边界的掩蔽条件都不影响词频效应,说明中文读者对词n+1处文字的预视加工达不到词汇水平。实验4考察剥夺预视加工的掩蔽条件、提示词n+1右侧边界的掩蔽条件对预测性效应的影响,结果发现,剥夺预视加工完全消除预测性效应,提示词n+1右侧边界则减少预测性效应,说明对词汇的预期加工是中文读者切分词n+1的参考线索。综合4项实验结果可知,中文读者较难通过自下而上的文字识别切分词n+1,自上而下的词汇预期则是切分词n+1的加工形式。     

Length,frequency, and predictability effects of words on eye movements in reading

We tested the effects of word length, frequency, and predictability on inspection durations (first fixation, single fixation, gaze duration, and reading time) and inspection probabilities during first‐pass reading (skipped, once, twice) for a corpus of 144 German sentences (1138 words) and a subset of 144 target words uncorrelated in length and frequency, read by 33 young and 32 older adults. For corpus words, length and frequency were reliably related to inspection durations and probabilities, predictability only to inspection probabilities. For first‐pass reading of target words all three effects were reliable for inspection durations and probabilities. Low predictability was strongly related to second‐pass reading. Older adults read slower than young adults and had a higher frequency of regressive movements. The data are to serve as a benchmark for computational models of eye movement control in reading.     

On the additive effects of stimulus quality and word frequency in lexical decision: evidence for opposing interactive influences revealed by RT distributional analyses

The joint effects of stimulus quality and word frequency in lexical decision were examined in 4 experiments as a function of nonword type (legal nonwords, e.g., BRONE, vs. pseudohomophones, e.g., BRANE). When familiarity was a viable dimension for word-nonword discrimination, as when legal nonwords were used, additive effects of stimulus quality and word frequency were observed in both means and distributional characteristics of the response-time distributions. In contrast, when the utility of familiarity was undermined by using pseudohomophones, additivity was observed in the means but not in distributional characteristics. Specifically, opposing interactive effects in the underlying distribution were observed, producing apparent additivity in means. These findings are consistent with the suggestion that, when familiarity is deemphasized in lexical decision, cascaded processing between letter and word levels is in play, whereas, when familiarity is a viable dimension for word-nonword discrimination, processing is discrete.     

Duration differences between rare and common words and their implications for the interpretation of word frequency effects

The spoken durations of rare and common words were compared in three experiments. Depending upon the task and the amount of practice, rare words (with frequencies less than 3 per million) were spoken as much as 24% slower than common words (with frequencies greater than 100 per million), when the words were equated for number of letters. This difference was observed even when the memory and lexical access demands of the task were minimized, and it can be explained by differences in the phonetic constituents of the two classes of words. The existence of these phonetic differences has been previously reported by Landauer and Streeter (1973) and by Zipf (1935). These findings argue against the view that all effects on the processing of accurately perceived words that are correlated with frequency may be unambiguously ascribed to operations that involve secondary memory (although this may be true of frequency effects per se). One recent experiment (Watkins, 1.977) is examined in light of these findings.     

On the processes underlying stimulus-familiarity effects in recognition of words and nonwords

The authors investigated the recognizability of recently studied word and nonword stimuli in relation to both experimentally controlled prior frequency of occurrence and, for words, normative frequency (assessed by counts of occurrences in printed English). The interaction between these variables was small and nonsignificant across all conditions of 2 experiments. Patterns of recognition measures in relation to controlled prior frequency, but not normative frequency, appeared interpretable in terms of response biases generated by long-term priming. Application of a global memory model and analyses of correlations among item categories yielded evidence for a lexicality dimension underlying normative-frequency effects and an implication that "word-frequency effects" on recognition are better termed lexicality effects.     

Repetition effects for words and nonwords as indexed by event-related fMRI: a preliminary study

We have previously shown differential effects of stimulus familiarity on the repetition-related responses in right fusiform cortex to both faces and symbols. Repetition of familiar stimuli produced a response decrease, whereas repetition of unfamiliar stimuli produced a response increase. In the present experiment, we used words and nonwords as the familiar and unfamiliar stimuli respectively. In this case, the only fusiform region showing the familiarity-by-repetition interaction was in anterior left fusiform. This left-lateralisation of the fusiform interaction is consistent with our hypothesis that these repetition-related effects occur in the same regions responsible for perceptual recognition of familiar stimuli.     

Same-different judgments with words and nonwords: The differential effects of relative size

Words were paired with words and nonwords with nonwords in a simultaneous matching task requiring a same-different judgment. A difference in size slowed “same” RTs for both words and nonwords, while “differ” RTs for both words and nonwords were unaffected. These results do not support Bruder and Silverman’s 1974 conclusion that the word processing system filters size. The effects of relative size differences were discussed in terms of (a) normalization procedures and (b) changes in states of evidence leading to alterations in a response selection stage.     

The effects of root frequency, word frequency, and length on the processing of prefixed English words during reading

Two experiments were performed to investigate the roles of root morpheme frequency and word frequency in the encoding of prefixed words in sentence context. Two alternative words, which were equated on other indices but differed with respect to either root morpheme frequency or word frequency, were embedded in the same sentence frame. In Experiment 1, there was a significant root morpheme frequency effect on gaze duration but only a marginal word frequency effect. Post hoc analyses indicated that word length influenced both effects, with word frequency effects predominating for shorter words and root morpheme effects predominating for longer words. In Experiment 2, word length was also manipulated. There was a significant root frequency effect for longer prefixed words and a significant word frequency effect for shorter prefixed words. The results were best explained by a dual-route model (with competing whole-word access and compositional routes), in which increasing word length inhibited the whole-word process, relative to the compositional route.     

Stroop-like serial position effects in color naming of words and nonwords

Color-naming latencies to noncolor words and nonwords were faster when the onset or final phoneme of the displays corresponded to the onset or final phoneme of the color response. For example, for displays printed in red, the word rack and nonword rask, which share the initial onset phoneme with the response, led to faster naming than did the control word chap and nonword chup. Conversely, when the onset or final phoneme of the displays matched the onset or final phoneme of a conflicting color response (e.g., rack printed in blue), latencies were longer than to control items. Facilitation effects were stronger than interference effects, and the onset phoneme facilitation effect was augmented by coloring only the initial letter in the display. It is hypothesized that nonlexical processes that govern the translation of print to speech may be a source of facilitation in Stroop-like tasks, whereas lexical processes are more likely to contribute to interference.     

Recognition of the stimulus degradation in the word frequency effect

Summary An experiment was designed to distinguish between two explanations of the word frequency effect, each accounting for the effect in terms of response bias. One explanation assumes that the bias affects a viewer's percept, the other a decision about what to report. Subjects were shown common and uncommon words, degraded to various degrees. Their task was to state what word was presented and to estimate its degree of degradation. A word frequency effect was demonstrated: the degree of actual degradation at which some arbitrary proportion of common words was correctly reported was greater than that at which the same proportion of uncommon words was correctly reported. In addition, subjects correctly assessed that the common words correctly reported were more degraded. The result was discussed with reference to the two versions of response bias theory.The discussion in this paper was materially assisted by comments made by Donald Broadbent, whose help is gratefully acknowledged.     

Reading aloud: qualitative differences in the relation between stimulus quality and word frequency as a function of context

Virtually all theories of visual word recognition assume (typically implicitly) that when a pathway is used, processing within that pathway always unfolds in the same way. This view is challenged by the observation that simple variations in list composition are associated with qualitative changes in performance. The present experiments demonstrate that when reading aloud, the joint effects of stimulus quality and word frequency on response time are driven by the presence/absence of nonwords in the list. Interacting effects of these factors are seen when only words appear in the experiment, whereas additive effects are seen when words and nonwords are randomly intermixed. One way to explain these and other data appeals to the distinction between cascaded processing (or interactive activation) on the one hand versus a thresholded mode of processing on the other, with contextual factors determining which mode of processing dominates.