Trial Outcomes & Findings for Brain Mechanisms of Human Motivation (NCT NCT01976975)

NCT ID: NCT01976975

Last Updated: 2021-08-04

Results Overview

The Probabilistic Reward Task (PRT) is a behavioral task that measures an individual's ability to learn to choose a more rewarding outcome versus a less rewarding one (Response Bias). The response bias score is a ratio of the number of times a participant correctly chooses the high reward stimulus (the "rich" stimulus) versus the low reward stimulus (the "lean" stimulus). Response bias scores range between -1 and +1. A higher Response Bias score indicates a stronger bias toward the rich stimulus, and a negative Response Bias indicates a stronger bias toward the lean stimulus. The Change-in-Response-Bias is calculated by subtracting Response Bias in block 1 (trials 0-100) of the task from Response Bias in block 3 (trials 201-300) of the task. This metric represents the degree to which an individual is able to update behavior as a function of the asymmetrical reinforcement schedule.

• Recruitment status: COMPLETED
• Target enrollment: 270 participants
• Primary outcome timeframe: Administered during the first session.
• Results posted on: 2021-08-04

Participant Flow

Participant milestones

Measure	Mood Disorder Patients Patients with depressive and/or manic or hypomanic symptoms	Healthy Controls Participants with no lifetime history of psychiatric illness
Overall Study STARTED	226	44
Overall Study COMPLETED	79	32
Overall Study NOT COMPLETED	147	12

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

The YMRS was not administered to subjects in the Healthy Control arm.

Baseline characteristics by cohort

Measure	Mood Disorder Patients n=226 Participants Patients with depressive and/or manic or hypomanic symptoms	Healthy Controls n=44 Participants Participants with no lifetime history of psychiatric illness	Total n=270 Participants Total of all reporting groups
Age, Categorical <=18 years	8 Participants n=226 Participants	3 Participants n=44 Participants	11 Participants n=270 Participants
Age, Categorical Between 18 and 65 years	218 Participants n=226 Participants	41 Participants n=44 Participants	259 Participants n=270 Participants
Age, Categorical >=65 years	0 Participants n=226 Participants	0 Participants n=44 Participants	0 Participants n=270 Participants
Age, Continuous	33 years n=226 Participants	30 years n=44 Participants	32 years n=270 Participants
Sex: Female, Male Female	140 Participants n=226 Participants	20 Participants n=44 Participants	160 Participants n=270 Participants
Sex: Female, Male Male	86 Participants n=226 Participants	24 Participants n=44 Participants	110 Participants n=270 Participants
Race (NIH/OMB) American Indian or Alaska Native	1 Participants n=226 Participants	0 Participants n=44 Participants	1 Participants n=270 Participants
Race (NIH/OMB) Asian	22 Participants n=226 Participants	11 Participants n=44 Participants	33 Participants n=270 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	1 Participants n=226 Participants	0 Participants n=44 Participants	1 Participants n=270 Participants
Race (NIH/OMB) Black or African American	32 Participants n=226 Participants	4 Participants n=44 Participants	36 Participants n=270 Participants
Race (NIH/OMB) White	144 Participants n=226 Participants	27 Participants n=44 Participants	171 Participants n=270 Participants
Race (NIH/OMB) More than one race	17 Participants n=226 Participants	2 Participants n=44 Participants	19 Participants n=270 Participants
Race (NIH/OMB) Unknown or Not Reported	9 Participants n=226 Participants	0 Participants n=44 Participants	9 Participants n=270 Participants
Region of Enrollment United States	226 Participants n=226 Participants	44 Participants n=44 Participants	270 Participants n=270 Participants
Beck Depression Inventory-II	27.87 units on a scale n=226 Participants	.32 units on a scale n=44 Participants	22.59 units on a scale n=270 Participants
Young Mania Rating Scale	1.97 units on a scale n=226 Participants • The YMRS was not administered to subjects in the Healthy Control arm.	—	1.97 units on a scale n=226 Participants • The YMRS was not administered to subjects in the Healthy Control arm.

PRIMARY outcome

Timeframe: Administered during the first session.

Population: Population includes patients and healthy controls who completed the PRT during the first session.

The Probabilistic Reward Task (PRT) is a behavioral task that measures an individual's ability to learn to choose a more rewarding outcome versus a less rewarding one (Response Bias). The response bias score is a ratio of the number of times a participant correctly chooses the high reward stimulus (the "rich" stimulus) versus the low reward stimulus (the "lean" stimulus). Response bias scores range between -1 and +1. A higher Response Bias score indicates a stronger bias toward the rich stimulus, and a negative Response Bias indicates a stronger bias toward the lean stimulus. The Change-in-Response-Bias is calculated by subtracting Response Bias in block 1 (trials 0-100) of the task from Response Bias in block 3 (trials 201-300) of the task. This metric represents the degree to which an individual is able to update behavior as a function of the asymmetrical reinforcement schedule.

Outcome measures

Measure	Mood Disorder Patients n=135 Participants Patients with depressive and/or manic or hypomanic symptoms	Healthy Controls n=34 Participants Participants with no lifetime history of psychiatric illness
Change in Response Bias	.0546 log-transformed ratio of scores Interval -0.6194 to 0.7074	.0787 log-transformed ratio of scores Interval -0.5408 to 0.7041

PRIMARY outcome

Timeframe: Administered in session 3 during 1.5 hour MR scan

Population: All participants who had readable Pessiglione task data

The instrumental learning task requires participants to choose between two abstract symbols. Each symbol in the pair is associated with an 80% or 20% probability of a given outcome (gain: win $1 or $0; loss: lose $1 or $0; neutral: view a gray square or see the word 'nothing'). The task consists of three blocks. Behavioral performance focuses on the number of times the participant chose the symbol that was associated more frequently associated with the more desirable outcome. A participant scores 1 if they choose correctly, and 0 if they choose in correctly, and correct choices across all three blocks are added and converted to a percentage relative to the total number of trials in that condition (i.e., gain, loss, or neutral). This study focused on percent of accuracy responses in the gain condition.

Outcome measures

Measure	Mood Disorder Patients n=77 Participants Patients with depressive and/or manic or hypomanic symptoms	Healthy Controls n=31 Participants Participants with no lifetime history of psychiatric illness
Mean Accuracy on Gain Trials During an Instrumental Learning Task	16.65 Percent of accurate responses Interval 10.33 to 21.33	17.03 Percent of accurate responses Interval 11.33 to 21.33

SECONDARY outcome

Timeframe: 6 months

Population: Population includes patients and controls who completed the 6-month follow up session

• Beck Depression Inventory (BDI-II). Severity of depressive symptoms, from 0 (no symptoms) to 63 (severely depressed)
• Young Mania Rating Scale (YMRS). Severity of manic symptoms, from 0 (not manic) to 60 (severely manic)
• Temporal Experience of Pleasure Scale (TEPS). The TEPS is an 18-item questionnaire. Ten items make up the TEPS-Anticipatory Pleasure scale with a range from 10 (not motivated) to 60 (highly motivated).
• The other eight TEPS items make up the TEPS-Consummatory Pleasure scale; range from 8 (not responsive) to 48 (highly responsive)
• Mood and Anxiety Symptom Questionnaire - Anhedonic Depression (MASQ-AD). The MASQ is a 62-item self-report on the severity of anxiety and depressive symptoms. The AD subscale is a 22-item measure of severity of anhedonic symptoms. Range: 22 -110 (higher scores mean greater severity)
• Barrett Impulsiveness Scale 11 (BIS-11): a 30-item assessment of Trait Impulsivity. Range: 30-120 (higher scores mean more impulsiveness)

Outcome measures

Measure	Mood Disorder Patients n=68 Participants Patients with depressive and/or manic or hypomanic symptoms	Healthy Controls n=30 Participants Participants with no lifetime history of psychiatric illness
Symptom Severity at 6 Month Follow-up BDI-II	15.24 units on a scale Interval 0.0 to 43.0	.33 units on a scale Interval 0.0 to 4.0
Symptom Severity at 6 Month Follow-up YMRS	1.41 units on a scale Interval 0.0 to 12.0	.07 units on a scale Interval 0.0 to 1.0
Symptom Severity at 6 Month Follow-up TEPS Anticipatory Pleasure Scale	39.41 units on a scale Interval 12.0 to 57.0	47.63 units on a scale Interval 38.0 to 58.0
Symptom Severity at 6 Month Follow-up TEPS Consummatory Pleasure Scale	36.54 units on a scale Interval 8.0 to 48.0	40.30 units on a scale Interval 26.0 to 48.0
Symptom Severity at 6 Month Follow-up MASQ-AD; Anhedonic Depression severity	70.59 units on a scale Interval 38.0 to 104.0	42.63 units on a scale Interval 22.0 to 69.0
Symptom Severity at 6 Month Follow-up BIS Impulsiveness	67.47 units on a scale Interval 44.0 to 93.0	47.93 units on a scale Interval 38.0 to 59.0

Adverse Events

Mood Disorder Patients

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Healthy Controls

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

David Crowley

McLean Hospital

Phone: 6178554432

Email: djcrowley@mclean.harvard.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place