Category Learning Retention in Adults With and Without Developmental Language Disorder
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age18-55
SponsorUniversity of Delaware
About this trial
Approximately 7% of the population experiences developmental language disorder (DLD), a language disorder with unclear causes. DLD affects communication beyond adolescence and poses challenges for education and career advancement due to difficulties in learning and memory. Recent research suggests that adults with DLD struggle with overnight memory consolidation, indicating a need for effective learning and memory support. This project aims to determine the optimal training schedule for perceptual memory retention in adults with and without DLD. The study involves recruiting 240 adults (120 with DLD, 120 without) for speech-perceptual training with different training schedules. The researchers predict that the manipulation of training schedules will interact with circadian preference and overnight consolidation, leading to the discovery of the best practice schedule for speech sound retention. Additionally, 300 more adults (150 with DLD, 150 without) will be recruited to investigate how optimal training schedules interact with reflexive and reflective learning strategies. The time course of learning and retention will be tracked during reflexive and reflective categorization training in six different training schedules.
Eligibility criteria
This trial accepts healthy volunteersQualifiers
native speakers of American English
Grew up in a household in which only American English was spoken
18-55 years of age
Typical vision & hearing
Disqualifiers
History of neurological disorders
History of psychiatric disorders
History of socio-emotional disorders
On prescription medication(s) that alter sleep
Trial design
Design model
Parallel
Treatments tested in this trial
Perceptual category training
BehavioralParticipants complete a forced-choice categorization task with feedback, in order to learn difficult auditory and visual categories
Treatment groups
540 Participants
are divided into 6 treatment groups6
Treatment groupsSee each treatment group below.
Group A: Blocked Evening Only TrainingExperimental treatment 1 intervention
Group B: Distributed Evening TrainingExperimental treatment 1 intervention
Group C: Blocked Evening-Morning TrainingExperimental treatment 1 intervention
Group D: Blocked Morning Only TrainingExperimental treatment 1 intervention
Group E: Distributed Morning TrainingExperimental treatment 1 intervention
Group F: Blocked Morning-Evening TrainingExperimental treatment 1 intervention
Trial outcomes
Primary outcomes
1
Speech discrimination - behavior
Participants will be administered a short (approximately 4-minute) behavioral task. They will be exposed to two speech sounds, separated by a 1-second interval. Some sounds will begin with the dental stop consonant, and other sounds will begin with the retroflex stop consonant. Participants will be asked to decide if the two sounds they hear are the same or different. Accuracy will be converted to d-prime (a measure of signal detection). This d-prime score will be the primary behavioral outcome for speech discrimination.
Time frame
1 week2
category identification - behavior
Participants will be administered a short (approximately 2 minutes) for each modality (auditory and visual). Participants will either hear (auditory - pure tone) or see (visual - gabor patch) a stimulus, and will need to choose which category the stimulus belongs to out of a choice of two. The percentage of trials that are answered correctly will be the primary behavioral outcome for auditory and visual category identification.
Time frame
48 hoursSecondary outcomes
1
Speech discrimination - Event-related potential of the electroencephalogram (ERP/EEG)
The investigators will fit the participant's head with a pre-positioned electrode cap, with electrolytic gel applied between the electrodes and the scalp. The participants will watch a silent movie while dental and retroflex speech tokens are presented in an oddball paradigm. The investigators will record the participants' electroencephalogram (EEG) while the auditory stimuli are presented. The EEG data will be segmented to examine the fluctuations in voltage recorded at the scalp (in milivolts) for a duration of one second after the onset of each stimulus. The segmented data will be averaged across dental trials, and across the retroflex trials. The resultant waveforms will be subtracted from one another. The peak of the deflection in the difference waveform found approximately 250miliseconds following stimulus onset is the mismatch negativity (MMN) component. The magnitude of the MMN component will be our primary outcome measure.
Time frame
1 event-related potential (ERP) session 1 week following trainingSponsors and contacts
Click on the lead sponsor to view all of their trials.
University of Delaware
Lead sponsor
Northeastern University
Collaborator
Source ClinicalTrials.gov