One in 10 people have a seizure during their life. Usually no cause is identified. Seizures without an identified cause are called unprovoked first seizure (UFS). Most people with UFS do not have further seizures. Being able to predict the risk of more seizures as soon as possible would help doctors decide whether to suggest treatment after UFS.

Studies show that seizures are associated with changes in brain structure and function that are difficult to detect with standard assessments but can be detected with advanced techniques. Changes in connections between brain regions are also linked to subtle problems in thinking and mood.

The investigators will examine brain connections using detailed brain scans, thinking, and mood in people with UFS and develop an accurate method for calculating the risk of further seizures.

200 adult patients and 75 matched healthy controls from the Halifax and Kingston First Seizure Clinics will undergo cognitive screening assessment of major cognitive domains, MRI imaging including structural scans, resting-state functional MRI (rsfMRI) and diffusion-weighted imaging (DWI), and EEG.

Seizure recurrence will be assessed prospectively and a multimodal machine learning model will be trained to predict seizure recurrence at 12 months.

Inclusion Criteria:

• This study will consider adult patients between the ages of 18-65 years seen in the First Seizure Clinics in Halifax and Kingston with unprovoked first seizure.
• The investigators will also include a sample of age, sex, and education-matched healthy controls with the same exclusion criteria.

Exclusion Criteria:

• Individuals over the age of 65 will not be included to reduce the probability of including individuals with early dementia.
• The investigators will also exclude individuals who, upon assessment during their first clinic appointment, are determined to have non-epileptic events, recurrent events or diagnosis of epilepsy (e.g. based on abnormal CT or EEG), provoked seizure (e.g. medication, substance misuse, metabolic), acute symptomatic seizures, those with an existing prescription for antiseizure drugs, significant CNS comorbidity that may affect cognition and brain networks (e.g. progressive neurological disorder, MS), previous neurosurgery, or contraindication to MRI.
• Finally, although there is no known risk to a fetus from MRI scanning, as is standard in research studies involving MRI, pregnant participants will be excluded and those that suspect that they may be pregnant require a negative pregnancy test before scanning.

Patients aged 18-65 years old with unprovoked first seizure; age, sex and education-matched healthy controls.

Multi-centre, the study population will consist of adults from across Atlantic Canada, and South-Eastern Ontario.