Chapter 1. Lexical Decision

1.1 Introduction

When you see a string of letters, it seems obvious whether the string of letters is a word or just random letters. It is not hard to tell the difference between “HELLO” and “HOLEL”: One is a word and one is not a word. When we ask participants to tell us whether a letter string is a word, we call it a lexical decision. Once a task like a lexical decision has been developed, this task can then be used to examine various features of how our cognition operates. In this experiment you will be using a lexical decision task to highlight features of how we store information about words in memory. It seems clear that we do not store information as isolated pieces. One item in memory forms connections with other items. This experiment will examine one of the implications for memories being interconnected.

Ratcliff, R., Gomex, P., & McKoon, G. (2004). A diffusion model account of the lexical decision task. Psychological Review, 111, 159-182.

1.2 Experiment Setup

1.3 Instructions

You will need to press the space bar to begin the experiment. A fixation mark will then appear in the center of the screen. Please look at this mark. After a brief period, it will be replaced by the prime stimulus, either a word or a string of letters that do not create a word. There will then be another blank interval, followed by the target stimulus, which will be either a word or not a word. Your task is to indicate if the second set of letters is a word or not a word as quickly and accurately as possible.

Keyboard Responses

1.4 Experiment

1.5 Results

1.6 Quiz