# README

This fMRI dataset was acquired in 2021-2022 as part of the CANDICE (Cerebral Asymmetry: New Directions in Correlates and Etiology) project, PI Dorothy Bishop, University of Oxford.

Scanning took place at two sites: Bangor (BAN) and Oxford (OXF). All participants had previously participated in an online behavioural testing session and an in-person session using functional transcranial doppler sonography (fTCD). 

The aim of the fMRI study was to test how closely laterality indices derived from fTCD and fMRI correlated. The raw fMRI data is provided her, and the participants.tsv file contains laterality indices (LIs) derived from the fTCD data.

Ethics approval was obtained separately at each site:
Oxford: Medical Sciences Interdivisional Research Ethics Committee: R53052_RE002
Bangor: School of Psychology Ethics and Research Committee: 2021-16965.

## Further materials 

The task scripts and stimuli are available to download from OSF (https://osf.io/zg8nx/).

The MR protocol for the Oxford site is available here: https://open.win.ox.ac.uk/protocols/stable/8307b825-3fba-44fb-a930-7dea244a0f5c. 

The data from the online tasks and fTCD session are available on OSF (https://osf.io/g9tqh/). The linkage information between the two studies is available on request.

## fMRI Tasks

Six language tasks were administered in the fMRI sessions: 
A: Word Generation (WG)
B: Sentence Generation (SG)
C: Phonological Decision (PD)
D: Word Comprehension (WC)
E: Sentence Comprehension (SC)
F: Syntactic Decision (SD)

The tasks were identical to those administered in the fTCD session, except only 12 trials (blocks) per task were included for fMRI, and 18 for fTCD. A detailed description of the tasks is available in Parker et al., 2022 (Cortex; link TBC).

## Procedure

The fMRI session was always after the fTCD session. The delay between the two sessions is noted in participants.tsv.

Within the fMRI session, task order was counterbalanced between participants, and a code indicating the order given for each participant is available in participants.tsv. After a localiser scan, three tasks were administered, followed by a fieldmap and structural scan, then the final three tasks were administered. Total scan time was around 1 hour 15 minutes.

## Participants

Participants were neurotypical adults, aged 18-50 years, with no known history of neurological, psychiatric or language disorders such as dyslexia. All participants had normal hearing and normal or corrected to normal vision and had native level proficiency in English.

## Apparatus

In Oxford, participants used earplugs to protect hearing and wore Optoacoustic noise cancelling headphones to hear audio stimuli during the tasks. Spoken responses (during WG and SG tasks) were recorded using the Optoacoustics microphone.

In Bangor, no microphone was available for audio recordings.

## Missing Data

Participant sub-OXF13 did not perform the WC task.

Participant sub-OXF17 was repositioned in the scanner halfway through the experiment, so has two B0 fieldmaps. 
sub-OXF17_acq-func_run-01* should be used with SC, SD, SG and WC tasks.
sub-OXF17_acq-func_run-02* should be used with PD and SG tasks.