Maya M. Khanna

Age of acquisition predicts naming and lexical-decision performance above and beyond 22 other predictor variables: An analysis of 2,342 words

Age of acquisition (AoA) ratings were obtained and were used in hierarchical regression analyses to predict naming and lexical-decision performance for 2,342 words (from Balota, Cortese, Sergent-Marshall, Spieler, & Yap, 2004). In the analyses, AoA was included in addition to the set of predictors used by Balota et al. (2004). AoA significantly predicted latency performance on both tasks above and beyond the standard predictor set. However, AoA was more strongly related to lexical-decision performance than to naming performance. Finally, the previously reported effect of imageability on naming latencies by Balota et al. was not significant with AoA included as a factor. These results are consistent with the idea either that AoA has a semantic/lexical locus or that AoA effects emerge primarily in situations in which the input–output mapping is arbitrary.

Age of acquisition ratings for 3,000 monosyllabic words.

Age of acquisition (AoA) ratings made on a 1-7 scale for 3,000 monosyllabic words were obtained from 32 participants across four blocks of 750 trials (two blocks of 750 trials were completed in each of 2 days). These results, as well as those of the regression analyses and reliability and validity measures that were originally reported in Cortese and Khanna (2007), are summarized here. Here, we also report high interblock correlations across items, indicating that participants were consistent in their ratings across blocks. The norms for the 3,000 words are important for researchers interested in word processing and may be downloaded from the Psychonomic Society’s Norms, Stimuli, and Data archive at www.psychonomic.org/archive.

Effect of Attention Training on Attention Bias Variability and PTSD Symptoms: Randomized Controlled Trials in Israeli and U.S. Combat Veterans

OBJECTIVE Attention allocation to threat is perturbed in patients with posttraumatic stress disorder (PTSD), with some studies indicating excess attention to threat and others indicating fluctuations between threat vigilance and threat avoidance. The authors tested the efficacy of two alternative computerized protocols, attention bias modification and attention control training, for rectifying threat attendance patterns and reducing PTSD symptoms. METHOD Two randomized controlled trials compared the efficacy of attention bias modification and attention control training for PTSD: one in Israel Defense Forces veterans and one in U.S. military veterans. Both utilized variants of the dot-probe task, with attention bias modification designed to shift attention away from threat and attention control training balancing attention allocation between threat and neutral stimuli. PTSD symptoms, attention bias, and attention bias variability were measured before and after treatment. RESULTS Both studies indicated significant symptom improvement after treatment, favoring attention control training. Additionally, both studies found that attention control training, but not attention bias modification, significantly reduced attention bias variability. Finally, a combined analysis of the two samples suggested that reductions in attention bias variability partially mediated improvement in PTSD symptoms. CONCLUSIONS Attention control training may address aberrant fluctuations in attention allocation in PTSD, thereby reducing PTSD symptoms. Further study of treatment efficacy and its underlying neurocognitive mechanisms is warranted.

Imageability estimates for 3,000 disyllabic words

We provide imageability estimates for 3,000 disyllabic words (as supplementary materials that may be downloaded with the article from www.springerlink.com). Imageability is a widely studied lexical variable believed to influence semantic and memory processes (see, e.g., Paivio, 1971). In addition, imageability influences basic word recognition processes (Plaut, McClelland, Seidenberg, & Patterson, 1996). In fact, neuroimaging studies have suggested that reading high- and low-imageable words elicits distinct neural activation patterns for the two types e.g., Bedny & Thompson-Schill (Brain and Language 98:127–139, 2006; Graves, Binder, Desai, Conant, & Seidenberg NeuroImage 53:638–646, 2010). Despite the usefulness of this variable, imageability estimates have not been available for large sets of words. Furthermore, recent megastudies of word processing e.g., Balota et al. (Behavior Research Methods 39:445–459, 2007) have expanded the number of words that interested researchers can select according to other lexical characteristics (e.g., average naming latencies, lexical decision times, etc.). However, the dearth of imageability estimates (as well as those of other lexical characteristics) limits the items that researchers can include in their experiments. Thus, these imageability estimates for disyllabic words expand the number of words available for investigations of word processing, which should be useful for researchers interested in the influences of imageability both as an input and as an outcome variable.

Children's use of language context in lexical ambiguity resolution

Lexical ambiguity resolution was examined in children aged 7 to 10 years and adults. In Experiment 1, participants heard sentences supporting one (or neither) meaning of a balanced ambiguous word in a cross-modal naming paradigm. Naming latencies for context-congruent versus context-incongruent targets and judgements of the relatedness of targets to the sentence served as indices of appropriate context use. While younger children were faster to respond to related targets regardless of the sentence context, older children and adults showed priming only for context-appropriate targets. In Experiment 2, only a single-word context preceded the homophone, and in contrast to Experiment 1, all groups showed contextual sensitivity. Individual working-memory span and inhibition ability were also measured in Experiment 2, and more mature executive function abilities were associated with greater contextual sensitivity. These findings support a developmental model whereby sentential context use for lexical ambiguity resolution increases with age, cognitive processing capacity, and reading skill.

Recognition memory for 2,578 monosyllabic words

In two studies, participants studied 30 lists of 50 words and were tested on 30 lists of 100 words. Item-level multiple regression analyses were conducted on hits, false alarms, hits minus false alarms, d′, and C. The predictor variables were objective frequency, subjective frequency, imageability, orthographic similarity, phonological similarity, phonological-to-orthographic N (PON), age of acquisition (AoA), and word length. The regression equations accounted for 45.9% of the variance in hit rates, 14.9% of the variance in false alarm rates, and 29.2% of the variance in hits minus false alarms. Other noteworthy results were that: (a) hit rates positively correlated with false alarms, (b) objective frequency negatively correlated with both hit rates and false alarm rates, (c) AoA positively correlated with hit rates and negatively correlated with false alarm rates, (d) length negatively correlated with hit rates and positively correlated with false alarm rates, (e) orthographic uniqueness was positively correlated with hit rates and negatively correlated with false alarms, (f) PON positively correlated with false alarm rates, (g) imageability produced the typical mirror pattern, and (h) imageability and length were the strongest predictors of performance. Results were largely compatible with predictions made by single- and dual-process theories of recognition memory.

Attention training normalises combat-related post-traumatic stress disorder effects on emotional Stroop performance using lexically matched word lists

ABSTRACT We examined two groups of combat veterans, one with post-traumatic stress disorder (PTSD) (n = 27) and another without PTSD (n = 16), using an emotional Stroop task (EST) with word lists matched across a series of lexical variables (e.g. length, frequency, neighbourhood size, etc.). Participants with PTSD exhibited a strong EST effect (longer colour-naming latencies for combat-relevant words as compared to neutral words). Veterans without PTSD produced no such effect, t < .918, p > .37. Participants with PTSD then completed eight sessions of attention training (Attention Control Training or Attention Bias Modification Training) with a dot-probe task utilising threatening and neutral faces. After training, participants—especially those undergoing Attention Control Training—no longer produced longer colour-naming latencies for combat-related words as compared to other words, indicating normalised attention allocation processes after treatment.

Age of acquisition estimates for 3,000 disyllabic words.

Age of acquisition (AoA) ratings based on a 1-7 scale for 3,000 disyllabic words were obtained from 32 participants. We demonstrate that these estimates are both reliable and valid. These estimates add to those collected on monosyllabic words and are of value to researchers interested in factors that contribute to word processing. They also can be used in regression analyses on measures obtained from large databases, and can be used in conjunction with imageability ratings for the same word corpus to differentiate AoA from imageability.

Ungraded Pop Quizzes Test-Enhanced Learning Without All the Anxiety

In this study, I examined the impact of periodic pop quizzes on cumulative final exam scores. Specifically, I compared the impact of using no quizzes, graded quizzes, and ungraded quizzes on final exam scores of introductory psychology students. Quizzed students also completed a survey with questions probing how the students felt about the inclusion of quizzes in the course. Students taking ungraded pop quizzes outperformed students taking graded pop quizzes and students taking no quizzes on the final exam. Students taking ungraded pop quizzes felt positive about having quizzes in their classes. The current findings have implications for research on the mitigating impact of anxiety on test-enhanced learning and on pedagogical strategy selection for educators.

Veterans with post-traumatic stress disorder exhibit altered emotional processing and attentional control during an emotional Stroop task

BACKGROUND Post-traumatic stress disorder (PTSD) is often associated with attention allocation and emotional regulation difficulties, but the brain dynamics underlying these deficits are unknown. The emotional Stroop task (EST) is an ideal means to monitor these difficulties, because participants are asked to attend to non-emotional aspects of the stimuli. In this study, we used magnetoencephalography (MEG) and the EST to monitor attention allocation and emotional regulation during the processing of emotionally charged stimuli in combat veterans with and without PTSD. METHOD A total of 31 veterans with PTSD and 20 without PTSD performed the EST during MEG. Three categories of stimuli were used, including combat-related, generally threatening and neutral words. MEG data were imaged in the time-frequency domain and the network dynamics were probed for differences in processing threatening and non-threatening words. RESULTS Behaviorally, veterans with PTSD were significantly slower in responding to combat-related relative to neutral and generally threatening words. Veterans without PTSD exhibited no significant differences in responding to the three different word types. Neurophysiologically, we found a significant three-way interaction between group, word type and time period across multiple brain regions. Follow-up testing indicated stronger theta-frequency (4-8 Hz) responses in the right ventral prefrontal (0.4-0.8 s) and superior temporal cortices (0.6-0.8 s) of veterans without PTSD compared with those with PTSD during the processing of combat-related words. CONCLUSIONS Our data indicated that veterans with PTSD exhibited deficits in attention allocation and emotional regulation when processing trauma cues, while those without PTSD were able to regulate emotion by directing attention away from threat.