In this arm of the study participants will self-apply 40 sham tDCS stimulations with in-person supervision provided by trained study personnel. The self-applied intervention will continue 5 times per week over eight consecutive weeks. Treatment will occur in the home.

Pain intensity will be measured by PROMIS (Patient-Reported Outcomes Measurement Information System) Pain Intensity - Short Form 3a. This 3-item instrument assesses how much a person hurts. The first two items assess pain intensity utilizing a 7-day recall period (items include the phrase "the past 7 days") while the last item asks patients to rate their pain intensity "right now." Respondents report their pain on a 5-point scale: 1=Had no pain, 2=Mild, 3=Moderate, 4=Severe, and 5=Very severe.

Participants will be asked what pain and pain related medications they are taking including the dose of each medication and how often they take them. A worksheet will be personalized to each participant to minimize the amount of recording that participants have to do in this phase of the study. The Y axis will list the medication (if taken more than once a day, each time point will have its own line) while the X axis will have the dates these data need to be collected. The participant will indicate how many pills they took in the table itself. The total dose of each pain and pain-related medication taken over the 5-day recording periods will be compared.

Pain interference will be measured by PROMIS (Patient-Reported Outcomes Measurement Information System) Pain Interference - Short Form 6b. This 6-item instrument measures the self-reported impact of pain on a person's life and assesses the extent to which pain may interfere with engagement with social, cognitive, emotional, physical, and recreational activities over a 7-day recall period. Pain Interference also incorporates items problem sleep and enjoyment in life, though the item bank only contains one sleep item. Respondents report levels of pain interference on a 5-point scale: 1=Not at all, 2=A little bit, 3=Somewhat, 4=Quite a bit, and 5=Very much.

Depressive Symptoms will be measured by PHQ-8 (Patient Health Questionnaire). This 8-item instruments measures symptoms of depression over the past 2 weeks such as, 'feeling down, depressed, or hopeless' or 'poor appetite or overeating'. Respondents report level of depression symptoms on a 4-point scale: 0=not at all, 1=Several days, 2=More than half the days, and 3=Nearly every day. The overall score range is 0 to 24 with a higher score indicating higher depressive symptoms.

Quality of Life will be measured by the Quality of Life Questionnaire (WHOQOL-BREF), a 26-item widely used and validated measure developed by the World Health Organization. Specific domains asked looking back over the last 2 weeks include physical health (e.g., enough energy for everyday life), psychological health (e.g., frequency of negative feelings), social relationships (e.g., satisfaction of support from friends), and environment (e.g., access to health services). Respondents answer each question on a 5-point scale and are transformed linearly to an overall adjusted score ranging from 0 to 100; with a higher score indicating higher quality of life.

Satisfaction with the tDCS-TH device and procedure is assessed using the tDCS User Survey that includes 8 statements describing various aspects of user's experience, such as education and training on tDCS use, ease of the procedure, or user's interest in future use of the device. on the first 7 statements are rated on a 5-point scale with anchor points Strongly Agree- Strongly Disagree. The last question is an open ended question asking about challenges and ways to improve

Occurrence of the number of related side effects and adverse events will be compared between groups.

Occurrence of the number of probably related side effects and adverse events will be compared between groups.

Occurrence of the number of possibly related side effects and adverse events will be compared between groups.