Lexical Decision Task
A computerized lexical decision task was developed for use in studies of children and adolescents to assess their attentional orienting responses to words of different emotional valence. In the task participants are presented with a series of letter strings. These letter strings include emotionally-laden and neutral words, as well as non-words. Non-words were formed by altering one letter of each real word contained in the task (e.g., bomb – bemb). Emotionality of the words was derived from Toglia and Battig’s (1978) word norms. Frequency of usage data were derived from norms provided by Kucera and Francis (1967). The length, number of syllables, imagery/concreteness, and frequency of usage of the words were balanced across word type. The task uses only words composed of 4 letters or less that had a concreteness rating of 2.75 or greater (Toglia & Battig, 1978) such as glad (positive), bomb (negative), and boot (neutral). Words are presented horizontally and are not repeated during the task. The task consists of 36 practice trials and 180 experimental trials containing an equal number of words and nonwords.
Prior to participating in the task, participants complete a rating scale inventory on which they rate the emotionality of each word on a 1 to 5 Likert-type scale. Scores of 1 represent an extreme negative rating, scores of 5 represent an extreme positive rating, and scores of 3 represent neutral emotional ratings. Following completion of the scale, participants sit at a computer and are given instructions on how to complete the task. Participants are told to depress either a yes (“V”) key if the letters on screen spell a real word or depress the no (“N”) key if the letter strings did not form a real word. The letter strings are displayed in the center of a black computer screen. The height and width of the letters are .5 cm and .2 cm, respectively. These dimensions produce lexical stimuli that are approximately .5 cm tall and 1 cm wide. Each letter string remains on the computer screen until the participant responds. After each response, participants are given a break of 2000 ms before the appearance of the next lexical stimulus. Upon completion of 2 practice blocks consists of 18 stimuli each, participants begin the actual task consisting of 10 blocks of 18 stimuli separated by 20-second break intervals. After completion of the first 5 blocks, participants are allowed to take a longer break. The words and their companion non-words are randomly presented within each block. After the task, participants complete the Word Inventory to determine their ability to read the words presented in the task.
References
Kucera, H., & Francis, W. N. (1967). Computational analysis of present-day American English. Providence, RI: Brown University Press.
Toglia, M. P., & Battig, W. (1978). Handbook of semantic norms. Hillsdale, NJ: Lawrence Erlbaum.
Scores for Analyses
Two scores are calculated for data analyses. A positive difference score (NEU-POS) is calculated by subtracting each participant’s average response time to positive words from his or her average response time to neutral words. A negative difference score (NEU-NEG) is calculated by subtracting each participant’s average response time to negative words from his or average response time to neutral words. These difference scores assess the amount of recognition time facilitation exhibited in response to affective stimuli.
Material Necessary for Task
LDT Program Files To download these (compressed) files, you need to right-click or otherwise select “Save to disk.”
Publications Using Task
Frick, P.J., Cornell, A.H., Bodin, S.D., Dane, H.A., Barry, C.T., & Loney, B.R. (2003). Callous-Unemotional traits and developmental pathways to severe aggressive and antisocial behavior. Developmental Psychology, 39, 246-260.
Loney, B.R., Frick, P.J., Clements, C.B., Ellis, M.L., & Kerlin, K. (2003). Callous-unemotional traits, impulsivity, and emotional processing in antisocial adolescents. Journal of Clinical Child and Adolescent Psychology, 32, 66-80.