Abstract

  • The tendency to prefer smaller, immediate rewards over larger, delayed rewards is known as Delay Discounting (DD), and individual differences in DD has been implicated in a variety of psychiatric disorders.

  • DD offers insight into executive dysfunction and may be an important transdiagnostic marker for ADHD, OCD, Autism and other psychiatric and neurodevelopmental disorders.

  • Characterizing the shape of developmental trajectories in markers of executive function also offer key indicators of how psychiatric illness arises during childhood and adolescence.

  • While it is known that DD is an important transdiagnostic marker, developmental deviations in DD may play a key role in characterizing psychiatric illness and create a greater understanding of neurodevelopmental disorder etiology.

  • Our results support prior work showing that DD follows non-linear developmental trajectories that can function as transdiagnostic markers of psychiatric symptoms across a range of ages and diagnoses.

  • Importantly, these developmental trajectories are able to delineate sex related differences in ADHD and anxiety presentation, supporting prior work suggesting this may be the case.

  • Our results provide support for DD as a transdiagnostic marker of psychiatric illness in children and adolescents. Approximately 75% of lifetime mental illness is diagnosed before the age of 24.

  • Considering commonly used diagnostic taxonomies do not map onto underlying symptomatology, transdiagnostic markers of executive function, such as DD, are needed to elucidate psychiatric etiology.

  • Understanding the developmental trajectories of these markers will help inform the search for modifiable transdiagnostic targets for psychiatric intervention.

ADT-5

  • The ADT-5 was used to obtain individual discount rates by directly measuring k for six unique commodities.

  • The task was developed to rapidly assess discount rates in a short period of time (i.e., under 5 minutes) through the presentation of five trials for each commodity and it’s delayed amount (Koffarnus & Bickel, 2014).

  • The commodities used were $10; $1,000; $1,000, $1,000 presented at a time in the past ($1,000 Past); an “explicit zero” version of $1,000 ($1,000 Explicit 0); $1,000,000; and 10 servings of a snack.

  • The “explicit zero” re-frames the choice determination by a direct comparison of the immediate outcome as “$1000 [delay] and $0 now” and the delayed outcome as "$500 now and $0 in [delay]).

Delay Discounting Factors

Dimensionality Reduction

  • Parallel analysis suggests that the number of factors = 3 and the number of components = 1

Factor Structure

Sample Characteristics

Characteristic N (%)
Sex
Female 624 (33.86%)
Male 1219 (66.14%)
Age
5-9 780 (42.32%)
10-14 801 (43.46%)
15-18 262 (14.22%)
Household Income
<$50K 293 (18.58%)
$50K-$99K 359 (22.76%)
$100K+ 925 (58.66%)
Diagnosis
ADHD Combined 403 (21.87%)
ADHD Hyperactive 57 (3.09%)
ADHD Inattentive 444 (24.09%)
Anxiety 698 (37.87%)
Autism with ADHD 251 (13.62%)
Autism without ADHD 55 (2.98%)
Depression 164 (8.9%)
Learning Disorders 506 (27.46%)
Neuro-Atypical 1720 (93.33%)
Neuro-typical 123 (6.67%)
OCD 86 (4.67%)
ODD 274 (14.87%)

Subtype Models

WISC/WIAT Subtypes

Profiles

Network Plot

Diagnosis Distributions

Age Distributions

GAMs

Factor Comparison Group Sex s(Age) s(Age):Group
Factor 1 1 vs. 2 -2.95** -3.366** 0.655 1.756
1 vs. 3 -3.038** -1.709 0.731 0.537
2 vs. 3 -0.573 -1.247 12.575*** 0.577
Factor 2 1 vs. 2 -1.689 -2.046* 1.798 0.191
1 vs. 3 0.463 -2.323* 1.787 1.745
2 vs. 3 1.944 -0.802 0.527 1.198
Factor 3 1 vs. 2 -3.133** -0.952 18.156*** 1.662
1 vs. 3 -1.994* 0.327 19.198*** 1.786
2 vs. 3 0.497 -0.524 30.342*** 1.274

CBCL Subtypes

Profiles

Network Plot

Diagnosis Distributions

Age Distributions

GAMs

Factor Comparison Group Sex s(Age) s(Age):Group
Factor 1 1 vs. 2 -0.719 -1.576 2.54* 0.055
1 vs. 3 -1.945 -1.109 4.79* 0.519
1 vs. 4 -1.057 -0.991 4.732* 0.858
2 vs. 3 -0.886 -2.18* 5.645* 1.497
2 vs. 4 -0.393 -2.224* 5.322* 2.042
3 vs. 4 0.752 -1.594 2.695 1.412
Factor 2 1 vs. 2 -0.436 -1.218 5.638* 6.055**
1 vs. 3 -0.058 -1.227 5.542* 2.38
1 vs. 4 -0.798 -0.572 5.673* 1.744
2 vs. 3 0.069 -0.452 2.103 1.467
2 vs. 4 -0.51 0.167 2.311 2.315
3 vs. 4 -0.671 0.165 0.325 1.484
Factor 3 1 vs. 2 -1.101 -0.621 9.773*** 0.247
1 vs. 3 -1.338 0.131 14.786*** 1.277
1 vs. 4 -2.174* -0.53 15.808*** 0.869
2 vs. 3 0.108 -0.006 17.12*** 2.772
2 vs. 4 -1.141 -0.841 17.656*** 0.663
3 vs. 4 -0.981 0.066 12.17*** 1.834

Diagnosis Models

Diagnosis vs. Neuro-typicals

Factor Comparison Group Sex s(Age) s(Age):Group
Factor 1 ADHD Combined 2.857** 0.617 3.38 0.856
ADHD Hyperactive 1.427 -1.237 3.994* 2.382
ADHD Inattentive 1.103 -0.651 3.11* 0.022
Anxiety 1.071 -2.431* 2.797* 0.229
Autism with ADHD 0.553 -1.986* 2.561 0.537
Autism without ADHD 0.691 -0.547 2.813* 0.515
Depression 0.64 -0.98 3.379* 1.787
Learning Disorders 2.052* -0.713 2.087 1.216
Neuro-Atypical 1.54 -2.165* 2.391 0.267
OCD 1.139 0.315 1.926 0.043
ODD 1.514 -2.442* 4.224* 0.886
Factor 2 ADHD Combined 1.885 1.418 0.002 1.05
ADHD Hyperactive -0.114 -0.612 0.008 0.988
ADHD Inattentive 1.896 -1.062 0.015 0.128
Anxiety 1.866 -1.262 0.015 2.313
Autism with ADHD 1.734 0.061 0.003 0.647
Autism without ADHD -1.478 -0.331 0 0.043
Depression 1.228 -0.486 0.012 4.016*
Learning Disorders 2.102* 0.254 0.003 2.351
Neuro-Atypical 1.807 -0.757 0.006 2.968
OCD 1.266 0.028 0 0.391
ODD 1.41 -1.225 0.02 3.409*
Factor 3 ADHD Combined 2.267* 1.7 10.732** 0.794
ADHD Hyperactive -0.246 -1.646 9.889*** 0.456
ADHD Inattentive -0.237 -0.48 5.907** 0.731
Anxiety 0.284 -0.792 5.775** 0.175
Autism with ADHD 0.423 -1.682 5.599** 0.995
Autism without ADHD 1.916 -0.417 10.662** 0.478
Depression -0.859 -1.062 7.201** 2.098
Learning Disorders 0.845 -0.526 5.671** 1.915
Neuro-Atypical 0.746 -0.576 5.41** 0.459
OCD 0.476 0.511 11.19** 1.017
ODD 1.072 -1.454 10.311** 0.275

Diagnosis Males vs. Diagnosis Females

Factor Comparison Group s(Age) s(Age):Group
Factor 1 ADHD Combined 0.927 0.232 2.941
ADHD Hyperactive -0.799 1.51 9.029***
ADHD Inattentive -0.251 4.795* 1.11
Anxiety -2.223* 3.061 2.491
Autism with ADHD -1.797 7.773** 1.533
Autism without ADHD 0.297 0.775 0.031
Depression -0.669 2.125 1.309
Learning Disorders -0.495 2.328 0.106
Neuro-Atypical -2.023* 8.978** 2.118
Neuro-typical -0.746 4.198 0.731
OCD 1.233 0.972 0.537
ODD -2.319* 0.007 1.663
Factor 2 ADHD Combined 1.895 2.666 0.267
ADHD Hyperactive -0.308 4.14* 3.854*
ADHD Inattentive -1.08 0.699 0.852
Anxiety -1.205 1.986 1.505
Autism with ADHD 0.416 0.329 1.055
Autism without ADHD -0.483 0.629 0.816
Depression -0.391 2.81 0.003
Learning Disorders 0.4 1.475 0.343
Neuro-Atypical -0.706 4.992** 2.405
Neuro-typical 0.018 0.007 0.25
OCD 0.223 0.627 0.013
ODD -1.211 5.899** 0.961
Factor 3 ADHD Combined 2.306* 7.263** 3.844*
ADHD Hyperactive -1.06 1.889 6.836**
ADHD Inattentive 0.12 9.857*** 0.592
Anxiety -0.375 16.618*** 0.326
Autism with ADHD -1.227 11.301** 1.079
Autism without ADHD 0.764 2.93 1.033
Depression -0.626 5.045* 2.193
Learning Disorders -0.067 7.339** 0.109
Neuro-Atypical -0.324 40.118*** 0.049
Neuro-typical -0.997 7.511** 1.43
OCD 1.883 0.001 2.637
ODD -1.005 8.061** 1.934

Diagnosis Males vs. Neuro-typical Males

Factor Comparison Group s(Age) s(Age):Group
Factor 1 ADHD Combined 1.576 3.927 2.214
ADHD Hyperactive 0.254 3.827* 0.01
ADHD Inattentive 0.712 1.804 0.26
Anxiety 1.05 1.857 0.757
Autism with ADHD 1.038 4.137* 0.147
Autism without ADHD 0.311 4.57 2.006
Depression 0.975 1.944 0.399
Learning Disorders 1.497 3.705 0.932
Neuro-Atypical 1.237 4.077 0.643
OCD 0.367 0.955 0.052
ODD 1.589 3.789 1.428
Factor 2 ADHD Combined 0.63 0.085 1.654
ADHD Hyperactive -0.323 0.01 1.992
ADHD Inattentive 1.717 0.081 0.559
Anxiety 1.612 0.08 2.33
Autism with ADHD 1.272 0.046 0.909
Autism without ADHD -1.195 0.012 0.315
Depression 1.179 0.082 3.308*
Learning Disorders 1.2 0.076 1.757
Neuro-Atypical 1.326 0.079 4.722**
OCD 0.711 0.026 0.159
ODD 1.409 0.077 3.968*
Factor 3 ADHD Combined 0.61 7.88*** 2.012
ADHD Hyperactive -1.215 8.35** 1.37
ADHD Inattentive -0.471 8.578*** 0.951
Anxiety -0.228 8.072*** 1.135
Autism with ADHD 0.514 5.569** 1.705
Autism without ADHD 1.154 5.91** 0.196
Depression -0.724 9.478*** 1.193
Learning Disorders 0.334 7.913*** 3.095*
Neuro-Atypical 0.113 7.141** 1.515
OCD -1.047 7.643** 2.379
ODD 0.824 8.77** 1.746

Diagnosis Females vs. Neuro-typical Females

Factor Comparison Group s(Age) s(Age):Group
Factor 1 ADHD Combined 2.376* 0.715 0.57
ADHD Hyperactive 2.372* 0.957 8.529***
ADHD Inattentive 0.826 0.292 0.246
Anxiety 0.244 0.296 0.605
Autism with ADHD -0.685 1.102 0.358
Autism without ADHD 0.942 0.701 0.069
Depression -0.366 0.763 1.756
Learning Disorders 1.32 0.636 0.361
Neuro-Atypical 0.831 0.258 0.314
OCD 1.672 1.031 0.333
ODD 0.397 1.043 0.376
Factor 2 ADHD Combined 1.883 0.02 0.113
ADHD Hyperactive 0.918 0.025 3.446*
ADHD Inattentive 0.906 0.023 0.239
Anxiety 0.972 0.025 0.613
Autism with ADHD 1.178 0.025 0.693
Autism without ADHD -0.699 0.022 0.445
Depression 0.547 0.025 0.876
Learning Disorders 1.531 0.018 0.451
Neuro-Atypical 1.12 0.013 0.06
OCD 1.081 0.022 0.227
ODD 0.56 0.026 0.042
Factor 3 ADHD Combined 2.774** 2.881 2.321
ADHD Hyperactive 1.646 3.808 8.101**
ADHD Inattentive 0.1 3.074 0.421
Anxiety 0.362 3.226 0.747
Autism with ADHD -0.293 3.67 1.203
Autism without ADHD 1.666 3.088 1.35
Depression -1.244 3.952* 2.245
Learning Disorders 0.803 2.881 0.165
Neuro-Atypical 0.769 2.84 1.441
OCD 1.798 3.233 1.76
ODD 0.835 3.292 2.036