This protocol offers an effective means for investigating the experimental effects of online sentence processing in different age groups and can overcome the problems with ad tracking in self-paced reading tasks. Using this technique, we can accurately measure the reading times of each segment in the sentences enabling us to precisely locate the processing difficulty in sentence comprehension. Demonstrating the procedure will be Liu Chong, a student from my department.
Before beginning the procedure, instruct the participant to sit at a computer workstation in the laboratory and ask the participant to read and sign the consent forms. After providing verbal instructions to the participant to ensure that they are clear about the requirements of the task, ask the participant to choose between the two words or phrases on the computer screen to form a grammatical continuation of the sentence. Inform the participant that their responses will be timed so they are expected to respond as quickly and as accurately as possible.
Next, present this message on the computer screen to the participant for their careful review and answer any questions that the participant may have about the instructions. Have the participant complete a small number of practice questions to ensure that they understand how to perform the task with the message incorrect appearing on the computer screen as feedback for any incorrect answers. When all of the practice questions have been completed, ask the participant to press the P button on the keyboard to repeat the practice session or to press the Spacebar to begin if they are ready to begin the experimental session.
During the task, the items should be presented on the computer screen as black letters on a white background. Have the participant read the items and for each segment use the F button to select the word on the left or the J button to select the word on the right. If the participant selects the correct answer, present the next pair of words.
When the wrong answer is selected, terminate the sentence and have the next sentence appear. For testing of the participant's working memory by the Wechsler Memory Scale, have the participant listen to a short sequence of digits that are presented auditorily at the rate of one digit per second. Then have the participant repeat the digit sequence in the same order using a digital recording device to record the participant's responses and recording the participant's responses on a record form.
At the end of the experiment, ask the participant to complete questionnaires about their background information including their age, gender, and years of education before compensating the participant for their participation. Here, the mean reading times by age group and word in each region for one representative experiment are shown. In this figure, the average reading times for older and younger adults for each region in the sentence are summarized for the same experiment.
The most important things to remember are to provide two alternatives for each segment in the sentences and to have participants choose between the two options. This technique can also be used to investigate the language comprehension deficits in patients with neurological diseases such as Alzheimer's or Parkinson's diseases.
