Emotion and Memory in Chronic Neuropathic Pain

Condition(s) studied

Investigational drug(s) / intervention(s)

Neuropsychological assessments: * Pain questionnaires such as Numerical Pain Rating Scale is one of the most widely used multidimensional pain scales to assesses a person's pain based on the words they use to describe their pain. * Battery of Cognitive questionnaires = The cognitive test battery was designed to assess key cognitive abilities including attention, concentration, verbal learning and memory, verbal fluency, working memory and executive function as well as global cognitive functioning and fear and anxiety * Mnemonic Simulation Test and Rey Auditory Verbal Learning Test are the neuropsychological assessments designed to evaluate recognition and verbal memory, respectively. Both tasks have been shown to be very sensitive to hippocampal engagement and damage. * Memory-recall interview is an interview for the interviewees to recall the event from different perspectives, such as from the preadmission date, 2-week post- and 6-month post-surgical date. This supports the memory retrieval process.

MR Imaging: Magnetic Resonance Imaging is a noninvasive medical imaging test that produces detailed images of almost every internal structure in the human body, including the organs, bones, muscles and blood vessels. MRI scanners create images of the body using a large magnet and radio waves.

Study summary

Chronic pain affects one in four Canadians, leading to severe personal and societal costs. Over 70% of chronic pain patients report memory difficulties and fear having unexpected pain. Abnormalities in brain structures associated with emotion and memory, including the hippocampus and amygdala, can be affected by chronic pain. Understanding the relationship between chronic pain, structural brain changes, and cognitive functioning will lead to improved diagnosis, treatment, and outcomes in chronic pain disorders. In this project, the investigators will use advanced brain imaging techniques that assess the structure and function of the brain along with cognitive assessments to examine the overlap between chronic pain and emotion-memory processes. The study team will conduct the study using an excellent model of chronic pain-trigeminal neuralgia, a severe form of facial pain that responds well to surgical treatment. Brain images and cognitive data will be collected from participants before and after surgical treatment for pain. This information will be analyzed and compared with age- and sex-matched healthy individuals. This study will be the first to thoroughly investigate relationships between brain structure and function, cognition (memory, emotion), and promises to impact our understanding of chronic neuropathic pain conditions.

Eligibility

Primary outcome measure(s)

• Beck Depression Inventory — For HC and TN > Neuropsychological assessments at baseline to screen for inclusion/exclusion criteria
  The Beck Depression Inventory (BDI) will be included in our battery of neuropsychological assessments that will be conducted on both HC and TN groups to screen for study inclusion and exclusion criteria. The BDI consists of 21 questions on which patients must score themselves on a scale from zero to three. The BDI is scored out of 63 with a score over 31 representing severe depression.
• Behavioural Inhibition System — For HC and TN > Neuropsychological assessments at baseline to screen for inclusion/exclusion criteria
  The Behavioural Inhibition System (BIS) will be included in our battery of neuropsychological assessments that will be conducted on both HC and TN groups to screen for study inclusion and exclusion criteria. The BIS is a 20 question, self-assessment that measures trait sensitivity levels of the behavioral inhibition and activation systems.
• Anxiety Sensitivity Index — For HC and TN > Neuropsychological assessments at baseline to screen for inclusion/exclusion criteria
  The Anxiety Sensitivity Index (ASI) will be included in our battery of neuropsychological assessments that will be conducted on both HC and TN groups to screen for study inclusion and exclusion criteria. The ASI is a six item scale that can outline different concerns someone could have regarding their anxiety.
• Beck's Hopelessness Scale — For HC and TN > Neuropsychological assessments at baseline to screen for inclusion/exclusion criteria
  The Beck Hopelessness Scale (BHS) will be included in our battery of neuropsychological assessments that will be conducted on both HC and TN groups to screen for study inclusion and exclusion criteria.
• Marlowe Crowne Scale — For HC and TN > Neuropsychological assessments at baseline to screen for inclusion/exclusion criteria
  The Marlowe Crowne Scale (MCS) will be included in our battery of neuropsychological assessments that will be conducted on both HC and TN groups to screen for study inclusion and exclusion criteria.
• Childhood Trauma Questionnaire — For HC and TN > Neuropsychological assessments at baseline to screen for inclusion/exclusion criteria
  The Childhood Trauma Questionnaire (CTQ) will be included in our battery of neuropsychological assessments that will be conducted on both HC and TN groups to screen for study inclusion and exclusion criteria.
• Structural magnetic resonance imaging (MRI) — For HC > MRI at baseline. For TN > MRI at baseline (pre-surgery) and at 6-month post-surgical)
  The investigators will acquire prospective longitudinal structural imaging data in 170 Trigeminal Neuralgia (TN) (pre-/6-months post-surgery) and 170 healthy controls (HC) and obtain topologies and volumes of the hippocampus (HPC) subfields using the brain imaging analysis software including HippUnfold and FreeSurfer. The investigators will also analyze amygdala (AMG) nuclei volumes using FreeSurfer. The group comparisons of the HPC and AMG will be done in both inter-group (TN vs. HC) and intra-group (pre- vs. post-surgery).
• Mnemonic Similarity Test — For HC > MRI at baseline. For TN > MRI at baseline (pre-surgery) and at 6-month post-surgical)
  The Mnemonic Similarity Test will be used to compare HPC-dependent memory performance between TN and HC and examine the effect of surgery (pre- and post-) on performance. The investigators will assess whether HPC-dependent memory and HPC volumes/topologies normalize following surgical TN pain relief.
• Fear of Pain Questionnaire III — For HC > pain-related fear and anxiety assessments at baseline. For TN >> pain-related fear and anxiety assessments at baseline (pre-surgery) and at 6-month post-surgical
  The Fear of Pain Questionnaire III (FPQ-III) will be used as one of the pain-related fear and anxiety assessments to assess pain-related fear and anxiety in TN and HC groups. The investigators will assess whether the abnormalities of the AMG nuclei volume will be normalized after surgery and will correlate these findings with validated pain-related fear and anxiety assessments. The FPQ-III is a 30 item assessment on which individuals rate how fearful they are of certain pain experiences on a scale from one to five.
• Pain Catastrophizing Scale — For HC > pain-related fear and anxiety assessments at baseline. For TN >> pain-related fear and anxiety assessments at baseline (pre-surgery) and at 6-month post-surgical
  The Pain Catastrophizing Scale (PCS) will be used as one of the pain-related fear and anxiety assessments to assess pain-related fear and anxiety in TN and HC groups. The investigators will assess whether the abnormalities of the AMG nuclei volume will be normalized after surgery and will correlate these findings with validated pain-related fear and anxiety assessments. The PCS will help investigators quantify an individual's pain - how they feel and what they think about when experiencing something painful.
• State-Trait Anxiety Inventory — For HC > pain-related fear and anxiety assessments at baseline. For TN >> pain-related fear and anxiety assessments at baseline (pre-surgery) and at 6-month post-surgical
  The State-Trait Anxiety Inventory (STAI) will be used as one of the pain-related fear and anxiety assessments to assess pain-related fear and anxiety in TN and HC groups. The investigators will assess whether the abnormalities of the AMG nuclei volume will be normalized after surgery and will correlate these findings with validated pain-related fear and anxiety assessments. The STAI is commonly used to measure trait and state anxiety. This assessment consists of 20 items for assessing trait anxiety and 20 for state anxiety, each of which are rated on a 4-point scale.
• Pain Anxiety Symptoms Scale — For HC > pain-related fear and anxiety assessments at baseline. For TN >> pain-related fear and anxiety assessments at baseline (pre-surgery) and at 6-month post-surgical
  The Pain Anxiety Symptoms Scale (PASS-20) will be used as one of the pain-related fear and anxiety assessments to assess pain-related fear and anxiety in TN and HC groups. The investigators will assess whether the abnormalities of the AMG nuclei volume will be normalized after surgery and will correlate these findings with validated pain-related fear and anxiety assessments. The Pass-20 is a 20 item assessment that measures 4 distinct components of pain-related anxiety.
• Functional Magnetic Resonance Imaging (fMRI) — For HC >ES task-fMRI at baseline. For TN >> ES task-based fMRI at baseline (pre-surgery) and 6-months post-surgery
  The experimental functional magnetic resonance imaging (fMRI) task that is specifically designed to measure episodic simulation (ES) using both neutral and pain-related cues will be conducted. ES measures the capacity to imagine specific future personal events and is heavily dependent on limbic integrity. This, along with the recalled pain memory interview will allow the investigators to correlate task-based fMRI findings with pain-recall discrepancies (discrepancies between recalled and initial pain ratings) and surgical response.
• Recalled pain memory interview — For HC > recalled pain at baselines. For TN >> recalled pain at baseline (pre-surgery) and at 2 weeks and 6-month post-surgery
  The recalled pain interview, focused on the recall of pain events, will be conducted and analyzed with a specific focus on the discrepancies in pain recall (referred to as autobiographical memory, AM). Recalled Pain questionnaires will take place at baseline (\~1 week prior to surgery, for the recall of pain onset and experience), acute recovery (2 weeks post-surgery) and 6 months post-surgery for recalled pain. These interview questionnaires will assess pain frequency, duration, intensity, fear, anxiety, unpleasantness, and interference.

Trial sites (1)

More University Health Network, Toronto trials in Canada

Other trials for the same condition