Speeded visual word naming and lexical decision performance are reported for 2,428 words for young adults and healthy older adults. Hierarchical regression techniques were used to investigate the unique predictive variance of phonological features in the onsets, lexical variables (e.g., measures of consistency, frequency, familiarity, neighborhood size, and length), and semantic variables (e.g., imageability and semantic connectivity). The influence of most variables was highly task dependent, with the results shedding light on recent empirical controversies in the available word recognition literature. Semanticlevel variables accounted for unique variance in both speeded naming and lexical decision performance, with the latter task producing the largest semantic-level effects. Discussion focuses on the utility of large-scale regression studies in providing a complementary approach to the standard factorial designs to investigate visual word recognition. The study of the processes involved in isolated word recognition has been central to developments in experimental psychology since the days of Cattell (1886). Researchers have accumulated a vast amount of information regarding the statistical properties of words, including word frequency, subjective familiarity, meaningfulness, letter frequency, bigram frequency, trigram frequency, spelling-to-sound consistency, syntactic class, and concreteness (see Balota, 1994, and Henderson, 1982 , for reviews). Word recognition research has been critical in developing computational models (e.g., Coltheart, Curtis, Atkins, & Haller, 1993; McClelland & Rumelhart, 1981; Plaut, McClelland, Seidenberg, & Patterson, 1996) , distinguishing between automatic and attentional processes (e.g., Fodor, 1983; Neely, 1977) , providing insights into reading acquisition (e.g., Perfetti, 1994) , and understanding neural substrates of language processing (e.g., Coltheart, Patterson, & Marshall, 1980; Petersen, Fox, Posner, Mintun, & Raichle, 1988) . One might argue that the word has been as central to developments in cognitive psychology and psycholinguistics as the cell has been to biology. Given the importance of word recognition research, one might assume that there are well-accepted methods for studying lexical processing. For example, probably the best way to study the integration of lexical information within reading is to analyze people's eye movements (e.g., eye fixation and gaze durations) as they are reading text (see Rayner, 1998; Rayner & Pollatsek, 1989) . However, during reading, there are multiple sources of information available (e.g., syntactic information, semantic constraints, parafoveal visual information), and so there are limits to this approach for models of isolated word recognition. Another procedure is to study how subjects identify words that are visually degraded by brief presentations and pattern masking. Unfortunately, there are also limitations with this procedure. Specifically, when subjects receive a degraded stimulus, they may rely on general knowledge about frequency and spelling patterns of words to make sophisticated guesses about the target stimulus (e.g., Broadbent, 1967; Catlin, 1973) . Because of the above concerns, researchers have continued to rely heavily on two measures: speeded lexical decision and naming performance. In the lexical decision task (LDT), subjects are presented with a visual string (either a word or a nonword, e.g., flirp), with their task being to decide as quickly as possible This work was supported by Grants AGO3991 and RO1 AG17024 from the National Institute on Aging and Grant BCS 0001801 from the National Science Foundation. We thank Keith Hutchison, Mark Law, Maura Pilotti, Martha Storandt, Michael Strube, and Jeff Templeton for their assistance in various stages of this project. In addition, we thank Brett Kessler, Rebecca Treiman, Barbara Juhasz, and Keith Rayner for helpful comments on an earlier version of this article. Finally, we thank Mark Steyvers for providing the connectivity estimates, Doug Nelson for providing the semantic set size estimates, Curt Burgess for providing the frequency estimates from the Hyperspace Analogue to Language database, and Brett Kessler and Rebecca Treiman for providing both their consistency estimates and their naming data. All item-level data are available at
Typically, two different techniques are used to study visual word recognition: the lexical decision tasks and the naming task REF ).
Visual word recognition of single-syllable words.
Journal of experimental psychology. General
Journal of experimental psychology. General
Psychology Medicine