What this trial measures

• Event-Based Prospective Memory - Number of Difficulty Ratings ProvidedThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Event-based prospective memory will be assessed using a difficulty ratings task. At the beginning of the session, participants will be asked to try to remember to rate how difficult they found each test immediately after it is completed, using a 0 (not at all difficult) to 10 (extremely difficult) scale. The primary outcome of interest is the number of difficulty ratings they remember to provide.

• Time-Based Prospective Memory - Token TaskThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Time-based prospective memory will be assessed using a token task. Participants will be instructed to try to remember to request a token every 10 minutes. A clock will be positioned face down on the table for them to refer to the time, and we will record their clock-checking behavior. The primary outcome is the number of times they remember to request the token, out of the total time of the cognitive assessment session.

• Cognitive Flexibility - N-back Test AccuracyThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Cognitive flexibility and working memory updating will be assessed using the N-back test. Participants are shown strings of letters one at a time and are instructed to indicate whenever a letter appears that matches the letter shown two trials earlier. Outcomes include the percentage of correct responses made (i.e., the number of times they correctly recognize that the current letter matches the one from two trials before, etc.).

• Cognitive Flexibility - N-back Reaction TimeThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Cognitive flexibility and working memory updating will be assessed using the N-back test. Participants are shown strings of letters one at a time and are instructed to indicate whenever a letter appears that matches the letter shown two trials earlier. Outcomes include the mean reaction time (milliseconds) for correct responses on the task.

• Cognitive Flexibility - N-back ERPThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Cognitive flexibility and working memory updating will be assessed using the N-back test. Participants are shown strings of letters one at a time and are instructed to indicate whenever a letter appears that matches the letter shown two trials earlier. The Muse S Athena wearable EEG device will capture time-locked event-related potential data during this task.

• Verbal Working Memory - Digit Span BackwardsThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Verbal working memory will be assessed using the Backwards portion of the Digit Span Test. For this test, participants are read lists of digits (of increasing lengths) and are asked to recall them in reverse order. The primary outcome of interest is the total number of correct trials.

• Planning - Tower Test Total Achievement ScoreThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Planning and problem-solving abilities will be assessed using the Tower Test. Participants are asked to move disks to reach a specified end configuration in as few moves as possible. They can move only one disk at a time and cannot place a larger disk on top of a smaller disk. Outcomes on this task include the Total Achievement Score across the tower problems, which reflects planning effectiveness.

• Planning - Tower Test Rule ViolationsThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Planning and problem-solving abilities will be assessed using the Tower Test. Participants are asked to move disks to reach a specified end configuration in as few moves as possible. They can move only one disk at a time and cannot place a larger disk on top of a smaller disk. Outcomes on this task include the number of rule violations (e.g., moving stacking a larger disk on top of a smaller one).

• Planning - Zoo Maps Test Total Achieved ScoreThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Planning and strategic thinking will be assessed using the Zoo Maps Test. Participants must plan a route through a provided zoo map while adhering to specified rules and efficiency constraints. For example, they may be instructed to start at the entrance, end at the picnic area, and use the designated paths only once. Outcomes on this task include the total achieved score, representing accuracy when generating a self-directed route under the provided constraints.

• Planning - Zoo Maps Test Rule ViolationsThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Planning and strategic thinking will be assessed using the Zoo Maps Test. Participants must plan a route through a provided zoo map while adhering to specified rules and efficiency constraints. For example, they may be instructed to start at the entrance, end at the picnic area, and use the designated paths only once. Outcomes on this task include the number of rule violations on the task.

• Inhibitory Control - Stroop Test Interference ScoreThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Inhibitory control will be assessed using the Stroop test. Participants will be shown words whose letters are in a specific color (e.g., the word "blue" in red letters. They will be tasked with naming the color of the word, which may be incongruent with the word itself. Outcomes on this task include the interference score, which reflects the difference in reaction times between the incongruent and congruent trials.

• Inhibitory Control - Stroop Test AccuracyThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Inhibitory control will be assessed using the Stroop test. Participants will be shown words whose letters are in a specific color (e.g., the word "blue" in red letters. They will be tasked with naming the color of the word, which may be incongruent with the word itself. Outcomes on this task include the percentage of correct responses on incongruent trials.

• Inhibitory Control - Stroop Test ERPThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Inhibitory control will be assessed using the Stroop test. Participants will be shown words whose letters are in a specific color (e.g., the word "blue" in red letters. They will be tasked with naming the color of the word, which may be incongruent with the word itself. The Muse S Athena wearable EEG device will capture time-locked event-related potential data during this task.

• Inhibitory Control - Flanker Test Interference ScoreThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Inhibitory control and attention will be assessed using the Flanker Test. Participants will respond to a central target stimulus (e.g., an arrow pointing in one direction) while ignoring surrounding distractor stimuli, that may be either congruent (e.g., an arrow pointing the same way) or incongruent (e.g., an arrow pointing the opposite way). Outcomes on this task include the interference score, which is the difference in reaction time between incongruent and congruent trials.

• Inhibitory Control - Flanker Test AccuracyThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Inhibitory control and attention will be assessed using the Flanker Test. Participants will respond to a central target stimulus (e.g., an arrow pointing in one direction) while ignoring surrounding distractor stimuli, that may be either congruent (e.g., an arrow pointing the same way) or incongruent (e.g., an arrow pointing the opposite way). Outcomes on this task include the percentage of correct responses across trial types.

• Inhibitory Control - Flanker Test ERPThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Inhibitory control and attention will be assessed using the Flanker Test. Participants will respond to a central target stimulus (e.g., an arrow pointing in one direction) while ignoring surrounding distractor stimuli, that may be either congruent (e.g., an arrow pointing the same way) or incongruent (e.g., an arrow pointing the opposite way). The Muse S Athena wearable EEG device will capture time-locked event-related potential data during this task.

• Cognitive Control - Oddball Task Target Detection AccuracyThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Cognitive control and sustained attention will be assessed using the Oddball Task. Participants will be asked to tap the screen when they see an infrequent red ball stimulus, and refrain from tapping when they see a green ball stimulus. Outcomes include the percentage of correctly identified target stimuli.

• Cognitive Control - Oddball Task Target Reaction TimeThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Cognitive control and sustained attention will be assessed using the Oddball Task. Participants will be asked to tap the screen when they see an infrequent red ball stimulus, and refrain from tapping when they see a green ball stimulus. Outcomes include the mean reaction time (milliseconds) for responses to target stimuli.

• Cognitive Control - Oddball Task ERPThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Cognitive control and sustained attention will be assessed using the Oddball Task. Participants will be asked to tap the screen when they see an infrequent red ball stimulus, and refrain from tapping when they see a green ball stimulus. The Muse S Athena wearable EEG device will capture time-locked event-related potential data during this task.

• Cognitive Flexibility - Wisconsin Card Sorting Test Perseverative ErrorsThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Cognitive flexibility (attentional set-shifting) will be assessed using the Wisconsin Card Sorting Task (WCST). Participants will sort cards of various shapes, colors, and numbers to match an undisclosed rule. After each card placement, participants will receive either "correct" or "incorrect" feedback to help them deduce the sorting rule. The sorting rule will periodically and unpredictably change (typically after a series of correct responses), and the participant must then infer the new rule. Outcomes on this task include the number of perseverative errors (i.e., failure to switch sorting strategies when the old sorting rule becomes incorrect).

• Cognitive Flexibility - Wisconsin Card Sorting Test Categories CompletedThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Cognitive flexibility (attentional set-shifting) will be assessed using the Wisconsin Card Sorting Task (WCST). Participants will sort cards of various shapes, colors, and numbers to match an undisclosed rule. After each card placement, participants will receive either "correct" or "incorrect" feedback to help them deduce the sorting rule. The sorting rule will periodically and unpredictably change (typically after a series of correct responses), and the participant must then infer the new rule. Outcomes on this task include the total number of sorting categories correctly completed.

• Cognitive Flexibility - Wisconsin Card Sorting Test Failure-to-Maintain-Set ErrorsThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Cognitive flexibility (attentional set-shifting) will be assessed using the Wisconsin Card Sorting Task (WCST). Participants will sort cards of various shapes, colors, and numbers to match an undisclosed rule. After each card placement, participants will receive either "correct" or "incorrect" feedback to help them deduce the sorting rule. The sorting rule will periodically and unpredictably change (typically after a series of correct responses), and the participant must then infer the new rule. Outcomes on this task include the number of errors reflecting a breakdown in sustained performance (e.g., not following the correct sorting rule after having learned it and without feedback indicating the rule has changed).

• Cognitive Flexibility - Verbal Fluency, Category Switching FluencyThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Cognitive flexibility (category switching) will be assessed using the verbal fluency category switching task. Participants will be given two categories (e.g., fruits and furniture) and be asked to generate words that belong to those categories, in alternating order, within a time limit of 60 seconds. Outcomes on this task include the category fluency score, which is the number of correct words generated.

• Cognitive Flexibility - Verbal Fluency, Category Switching AccuracyThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Cognitive flexibility (category switching) will be assessed using the verbal fluency category switching task. Participants will be given two categories (e.g., fruits and furniture) and be asked to generate words that belong to those categories, in alternating order, within a time limit of 60 seconds. Outcomes on this task include category switching accuracy, which is the number of correct switches between the categories.

• Stressor Challenge - Maastricht Acute Stress Test Subjective Pain RatingsThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Participants will complete an acute stress challenge, involving alternating trials of a physical stressor (placing their hand in a cooler of cold water) and a cognitive stressor (mental arithmetic). Outcomes on this test include subjective pain ratings, which are collected after each cold water trial on a 0 (not at all painful) to 10 (extremely painful) scale.

• Stressor Challenge - Maastricht Acute Stress Test Subjective Stress RatingsThis outcome will be assessed during both sessions, within 90 minutes post-treatment.

  Participants will complete an acute stress challenge, involving alternating trials of a physical stressor (placing their hand in a cooler of cold water) and a cognitive stressor (mental arithmetic). Outcomes on this test include subjective stress ratings, which are collected after each mental math trial on a 0 (not at all stressed) to 10 (extremely stressed) scale.

• EEG PowerThis outcome will be continuously assessed during both sessions, from baseline (i.e., during the testing session but before treatment) through two hours post-treatment.

  The Muse S Athena wearable EEG device will be worn by participants for the duration of the session, up until they are left to relax and sober up at the end of the session. The EEG device will be continuously recording, to allow for later quantification of power (e.g., theta, gamma, etc.) using spectral density analysis.

• Awe RatingsThis outcome will be assessed during both sessions, within two hours post-treatment.

  Participants will complete ratings of awe after watching a brief (\~20 minute) nature video.

• Connectedness to Nature RatingsThis outcome will be assessed during both sessions, within two hours post-treatment.

  Participants will complete ratings of their feelings of connectedness to nature after watching a brief (\~20 minute) nature video.