Abstract
Although attention-deficit/hyperactivity disorder (ADHD) has been studied for over a century, it is only in the last 3–4 decades that it has been studied in adults, along with the emotional dysregulation (ED) that often occurs with it. Increasing evidence suggests high rates of ED or mood-related psychiatric comorbidities in adults with ADHD, and marked impairment when such problems co-occur with ADHD. Experts have suggested three main approaches to understanding the relationship of ED with adult ADHD: (1) as a subtype of the ADHD, (2) as a core feature of the ADHD, or (3) as a co-travelling symptom with it. While psychobiological factors contribute to the link between ED and ADHD, the relative contribution of genetic factors or other factors is unclear. Accurate assessment of ED in an adult ADHD requires a comprehensive clinical interview verifying the symptoms, course and impairment, and to rule out other psychiatric comorbidities and organic causes having similar symptoms. Various self-report and clinician-administered measures can also be useful. Psychotherapy and/or pharmacotherapy have proven effective for treating adults with ADHD and ED. Future research is needed to clarify how ADHD and ED are related, and how clinicians can more effectively diagnose and treat adults having both disorders.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Dulcan M. Practice parameters for the assessment and treatment of children, adolescents, and adults with attention-deficit/hyperactivity disorder. American Academy of Child and Adolescent Psychiatry. J Am Acad Child Adolesc Psychiatry. 1997;36(10):85S–121S.
Matte B, Rohde LA, Grevet EH. ADHD in adults: a concept in evolution. ADHD Atten Def Hyp Disord. 2012;4(2):53–62.
Polanczyk G, Rohde LA. Epidemiology of attention-deficit/hyperactivity disorder across the lifespan. Curr Opin Psychiatry. 2007;20(4):386–92.
Brown TE. Attention-deficit disorders and comorbidities in children, adolescents, and adults. 1st ed. Washington, DC: American Psychiatric Press; 2000.
Kessler RC, Adler L, Barkley R, Biederman J, Conners CK, Demler O, et al. The prevalence and correlates of adult ADHD in the United States: results from the National Comorbidity Survey Replication. Am J Psychiatry. 2006;163(4):716–23.
Barkley RA. Deficient emotional self-regulation: a core component of attention-deficit/hyperactivity disorder. J ADHD Relat Disord. 2010;1(2):5–37.
Willcutt EG. The prevalence of DSM-IV attention-deficit/hyperactivity disorder: a meta-analytic review. Neurotherapeutics. 2012;9(3):490–9.
Brod M, Pohlman B, Lasser R, Hodgkins P. Comparison of the burden of illness for adults with ADHD across seven countries: a qualitative study. Health Qual Life Outcomes. 2012;10:47.
Adler LA, Dirks B, Deas P, Raychaudhuri A, Dauphin M, Saylor K, et al. Self-reported quality of life in adults with attention-deficit/hyperactivity disorder and executive function impairment treated with lisdexamfetamine dimesylate: a randomized, double-blind, multicenter, placebo-controlled, parallel-group study. BMC Psychiatry. 2013;13:253.
Barkley RA, Fischer M. The unique contribution of emotional impulsiveness to impairment in major life activities in hyperactive children as adults. J Am Acad Child Adolesc Psychiatry. 2010;49(5):503–13.
Simon V, Czobor P, Balint S, Meszaros A, Bitter I. Prevalence and correlates of adult attention-deficit hyperactivity disorder: meta-analysis. Br J Psychiatry. 2009;194(3):204–11.
Still GF. Some abnormal psychical conditions in children: excerpts from three lectures. J Atten Disord. 2006;10(2):126–36.
Barkley RA, Murphy KR. Deficient emotional self-regulation in adults with ADHD: the relative contributions of emotional impulsiveness and ADHD symptoms to adaptive impairments in major life activities. J ADHD Relat Disord. 2010;1(4):5–28.
Wender PH. Attention-deficit hyperactivity disorder in adults. New York: Oxford University Press; 1995.
Corbisiero S, Morstedt B, Bitto H, Stieglitz RD. Emotional Dysregulation in adults with attention-deficit/hyperactivity disorder-validity, predictability, severity, and comorbidity. J Clin Psychol. 2017;73(1):99–112.
Reimherr FW, Williams ED, Strong RE, Mestas R, Soni P, Marchant BK. A double-blind, placebo-controlled, crossover study of osmotic release oral system methylphenidate in adults with ADHD with assessment of oppositional and emotional dimensions of the disorder. J Clin Psychiatry. 2007;68(1):93–101.
Reimherr FW, Marchant BK, Olsen JL, Halls C, Kondo DG, Williams ED, et al. Emotional dysregulation as a core feature of adult ADHD: its relationship with clinical variables and treatment response in two methylphenidate trials. J ADHD Relat Disord. 2010;1(4):53–64.
Robison RJ, Reimherr FW, Marchant BK, Kondo D, Lyon GJ, Olsen JL, et al. The use of emotional dysregulation as an endophenotype for genetic studies in adults with attention-deficit hyperactivity disorder. J ADHD Relat Disord. 2010;1(4):29–38.
Skirrow C, McLoughlin G, Kuntsi J, Asherson P. Behavioral, neurocognitive and treatment overlap between attention-deficit/hyperactivity disorder and mood instability. Expert Rev Neurother. 2009;9(4):489–503.
Biederman J, Monuteaux MC, Mick E, Spencer T, Wilens TE, Silva JM, et al. Young adult outcome of attention deficit hyperactivity disorder: a controlled 10-year follow-up study. Psychol Med. 2006;36(2):167–79.
Uchida M, Spencer TJ, Faraone SV, Biederman J. Adult outcome of ADHD: an overview of results from the MGH longitudinal family studies of pediatrically and psychiatrically referred youth with and without ADHD of both sexes. J Atten Disord. 2015;
Biederman J, Petty CR, Woodworth KY, Lomedico A, Hyder LL, Faraone SV. Adult outcome of attention-deficit/hyperactivity disorder: a controlled 16-year follow-up study. J Clin Psychiatry. 2012;73(07):941–50.
Shekim WO, Asarnow RF, Hess E, Zaucha K, Wheeler N. A clinical and demographic profile of a sample of adults with attention deficit hyperactivity disorder, residual state. Compr Psychiatry. 1990;31(5):416–25.
Biederman J, Rosenbaum JF, Bolduc-Murphy EA, Faraone SV, et al. A 3-year follow-up of children with and without behavioral inhibition. J Am Acad Child Adolesc Psychiatry. 1993;32(4):814–21.
Kessler RC, Adler L, Ames M, Demler O, Faraone S, Hiripi E, et al. The World Health Organization Adult ADHD Self-Report Scale (ASRS): a short screening scale for use in the general population. Psychol Med. 2005;35(2):245–56.
Surman CB, Biederman J, Spencer T, Miller CA, McDermott KM, Faraone SV. Understanding deficient emotional self-regulation in adults with attention deficit hyperactivity disorder: a controlled study. Atten Defic Hyperact Disord. 2013;5(3):273–81.
Skirrow C, Asherson P. Emotional lability, comorbidity and impairment in adults with attention-deficit hyperactivity disorder. J Affect Disord. 2013;147(1-3):80–6.
Factor PI, Reyes RA, Rosen PJ. Emotional impulsivity in children with ADHD associated with comorbid (not ADHD) symptomatology. J Psychopathol Behav Assess. 2014;36(4):530–41.
Adler LA, Faraone SV, Spencer TJ, Berglund P, Alperin S, Kessler RC. The structure of adult ADHD. Int J Methods Psychiatr Res. 2017;26(1):e1555.
Marchant BK, Reimherr FW, Robison D, Robison RJ, Wender PH. Psychometric properties of the Wender-Reimherr Adult Attention Deficit Disorder Scale. Psychol Assess. 2013;25(3):942–50.
American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 4th text revised ed., vol. 30. Washington, DC: American Psychiatric Association; 2000. p. 2009.
American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 5th ed. Arlington: American Psychiatric Association; 2013.
Martel MM. Research review: a new perspective on attention-deficit/hyperactivity disorder: emotion dysregulation and trait models. J Child Psychol Psychiatry. 2009;50(9):1042–51.
Kessler RC, Green JG, Adler LA, Barkley RA, Chatterji S, Faraone SV, et al. Structure and diagnosis of adult attention-deficit/hyperactivity disorder: analysis of expanded symptom criteria from the Adult ADHD Clinical Diagnostic Scale. Arch Gen Psychiatry. 2010;67(11):1168–78.
Christiansen H, Kis B, Hirsch O, Philipsen A, Henneck M, Panczuk A, et al. German validation of the Conners Adult ADHD Rating Scales-self-report (CAARS-S) I: factor structure and normative data. Eur Psychiatry. 2011;26(2):100–7.
Domes G, Lischke A, Berger C, Grossmann A, Hauenstein K, Heinrichs M, et al. Effects of intranasal oxytocin on emotional face processing in women. Psychoneuroendocrinology. 2010;35(1):83–93.
Frodl T, Reinhold E, Koutsouleris N, Reiser M, Meisenzahl EM. Interaction of childhood stress with hippocampus and prefrontal cortex volume reduction in major depression. J Psychiatr Res. 2010;44(13):799–807.
Rusch N, Weber M, Il'yasov KA, Lieb K, Ebert D, Hennig J, et al. Inferior frontal white matter microstructure and patterns of psychopathology in women with borderline personality disorder and comorbid attention-deficit hyperactivity disorder. Neuroimage. 2007;35(2):738–47.
Welborn BL, Papademetris X, Reis DL, Rajeevan N, Bloise SM, Gray JR. Variation in orbitofrontal cortex volume: relation to sex, emotion regulation and affect. Soc Cogn Affect Neurosci. 2009;4(4):328–39.
Schulz KP, Clerkin SM, Fan J, Halperin JM, Newcorn JH. Guanfacine modulates the influence of emotional cues on prefrontal cortex activation for cognitive control. Psychopharmacology (Berl). 2013;226(2):261–71.
Tajima-Pozo K, Bayon C, Diaz-Marsa M, Carrasco JL. Correlation between personality traits and testosterone concentrations in healthy population. Indian J Psychol Med. 2015;37(3):317–21.
Tajima-Pozo K, Yus M, Ruiz-Manrique G, Lewczuk A, Arrazola J, Montanes-Rada F. Amygdala abnormalities in adults with ADHD. J Atten Disord. 2016;
Wilbertz G, Trueg A, Sonuga-Barke EJ, Blechert J, Philipsen A, Tebartz van Elst L. Neural and psychophysiological markers of delay aversion in attention-deficit hyperactivity disorder. J Abnorm Psychol. 2013;122(2):566–72.
Faraone SV, Perlis RH, Doyle AE, Smoller JW, Goralnick JJ, Holmgren MA, et al. Molecular genetics of attention-deficit/hyperactivity disorder. Biol Psychiatry. 2005;57(11):1313–23.
Waldman ID, Rhee SH. Behavioral and molecular genetic studies. In: Sandberg S, editor. Hyperactivity and attention disorders of childhood. 2nd ed. Cambridge: Cambridge University Press; 2002. p. 290–335.
Dresler T, Barth B, Ethofer T, Lesch KP, Ehlis AC, Fallgatter AJ. Imaging genetics in adult attention-deficit/hyperactivity disorder (ADHD): a way towards pathophysiological understanding? Borderline Personal Disord Emot Dysregul. 2014;1:6.
Perry GML, Faraone SV. Molecular genetics of ADHD. In: Adler LA, Spencer TJ, Wilens TE, editors. Attention-deficit hyperactivity disorder in adults and children. Cambridge: Cambridge University Press; 2015. p. 223–32.
Faraone SV, Biederman J, Spencer T, Mick E, Murray K, Petty C, et al. Diagnosing adult attention deficit hyperactivity disorder: are late onset and subthreshold diagnoses valid? Am J Psychiatry. 2006;163(10):1720–9.
Anonymous. Collaborative possibilities for molecular genetic studies of attention deficit hyperactivity disorder: report from an international conference. The ADHD Molecular Genetics Network. Am J Med Genet. 2000;96(3):251–7.
Brunner HG, Nelen M, Breakefield XO, Ropers HH, van Oost BA. Abnormal behavior associated with a point mutation in the structural gene for monoamine oxidase A. Science (New York, NY). 1993;262(5133):578–80.
Sonuga-Barke EJ, Oades RD, Psychogiou L, Chen W, Franke B, Buitelaar J, et al. Dopamine and serotonin transporter genotypes moderate sensitivity to maternal expressed emotion: the case of conduct and emotional problems in attention deficit/hyperactivity disorder. J Child Psychol Psychiatry. 2009;50(9):1052–63.
Distel MA, Carlier A, Middeldorp CM, Derom CA, Lubke GH, Boomsma DI. Borderline personality traits and adult attention-deficit hyperactivity disorder symptoms: a genetic analysis of comorbidity. Am J Med Genet B Neuropsychiatr Genet. 2011;156B(7):817–25.
Storebo OJ, Simonsen E. Is ADHD an early stage in the development of borderline personality disorder? Nord J Psychiatry. 2014;68(5):289–95.
Adler L, Cohen J. Diagnosis and evaluation of adults with attention-deficit/hyperactivity disorder. Psychiatr Clin North Am. 2004;27(2):187–201.
Goodman DW, Thase ME. Recognizing ADHD in adults with comorbid mood disorders: implications for identification and management. Postgrad Med. 2009;121(5):20–30.
Adler LA, Shaw DM, Kovacs K, Alperin S. Diagnosing ADHD in children and adults. In: Adler LA, Spencer TJ, Wilens TE, editors. Attention-deficit hyperactivity disorder in adults and children. Cambridge: Cambridge University Press; 2015. p. 16–23.
Asherson P. Clinical assessment and treatment of attention deficit hyperactivity disorder in adults. Expert Rev Neurother. 2005;5(4):525–39.
Asherson P, Young AH, Eich-Hochli D, Moran P, Porsdal V, Deberdt W. Differential diagnosis, comorbidity, and treatment of attention-deficit/hyperactivity disorder in relation to bipolar disorder or borderline personality disorder in adults. Curr Med Res Opin. 2014;30(8):1657–72.
Murphy KR, Adler LA. Assessing attention-deficit/hyperactivity disorder in adults: focus on rating scales. J Clin Psychiatry. 2004;65(Suppl 3):12–7.
Reimherr FW, Marchant BK, Strong RE, Hedges DW, Adler L, Spencer TJ, et al. Emotional dysregulation in adult ADHD and response to atomoxetine. Biol Psychiatry. 2005;58(2):125–31.
Rosler M, Retz W, Fischer R, Ose C, Alm B, Deckert J, et al. Twenty-four-week treatment with extended release methylphenidate improves emotional symptoms in adult ADHD. World J Biol Psychiatry. 2010;11(5):709–18.
Conners CK, Erhardt D, Sparrow E. CAARS: Conner’s Adult ADHD Rating Scales: Multi-Health Systems Incorporated (MHS); 1999.
Gallagher R, Blader J. The diagnosis and neuropsychological assessment of adult attention deficit/hyperactivity disorder. Scientific study and practical guidelines. Ann N Y Acad Sci. 2001;931:148–71.
Brown TE. Attention-deficit disorder scales: manual. San Antonio: The Psychological Corporation; 1996.
Roth RM, Isquith PK, Gioia GA. BRIEF-A: Behavior Rating Inventory of Executive Function—adult version: professional manual. Lutz: Psychological Assessment Resources; 2005.
Isquith PK, Roth RM, Gioia GA. Behavior Rating Inventory of Executive Function—Adult Version (BRIEF-A) interpretive report. Lutz: Psychological Assessment Resources; 2006.
Kroenke K, Spitzer RL, Williams JBW. The PHQ-9: validity of a brief depression severity measure. J Gen Intern Med. 2001;16(9):606–13.
Beck AT, Ward CH, Mendelson M, Mock J, Erbaugh J. An inventory for measuring depression. Arch Gen Psychiatry. 1961;4:561–71.
Hirschfeld RM, Williams JB, Spitzer RL, Calabrese JR, Flynn L, Keck PE Jr, et al. Development and validation of a screening instrument for bipolar spectrum disorder: the Mood Disorder Questionnaire. Am J Psychiatry. 2000;157(11):1873–5.
Kessler RC, Akiskal HS, Angst J, Guyer M, Hirschfeld RM, Merikangas KR, et al. Validity of the assessment of bipolar spectrum disorders in the WHO CIDI 3.0. J Affect Disord. 2006;96(3):259–69.
Hays RD, Merz JF, Nicholas R. Response burden, reliability, and validity of the CAGE, Short MAST, and AUDIT alcohol screening measures. Behav Res Methods Instrum Comput. 1995;27(2):277–80.
Maisto SA, Carey MP, Carey KB, Gordon CM, Gleason JR. Use of the AUDIT and the DAST-10 to identify alcohol and drug use disorders among adults with a severe and persistent mental illness. Psychol Assess. 2000;12(2):186–92.
Pilowsky DJ, Wu L-T. Screening for alcohol and drug use disorders among adults in primary care: a review. Subst Abuse Rehabil. 2012;3:25–34.
Solanto MV. Psychosocial treatment of ADHD in adults. In: Adler LA, Spencer TJ, Wilens TE, editors. Attention-deficit hyperactivity disorder in adults and children. Cambridge: Cambridge University Press; 2015. p. 298–306.
Bramham J, Young S, Bickerdike A, Spain D, McCartan D, Xenitidis K. Evaluation of group cognitive behavioral therapy for adults with ADHD. J Atten Disord. 2009;12:434.
Solanto MV, Marks DJ, Mitchell KJ, Wasserstein J, Kofman MD. Development of a new psychosocial treatment for adult ADHD. J Atten Disord. 2008;11(6):728–36.
Solanto MV, Marks DJ, Wasserstein J, Mitchell K, Abikoff H, Alvir JM, et al. Efficacy of meta-cognitive therapy for adult ADHD. Am J Psychiatry. 2010;167(8):958–68.
Virta M, Vedenpaa A, Gronroos N, Chydenius E, Partinen M, Vataja R, et al. Adults with ADHD benefit from cognitive-behaviorally oriented group rehabilitation: a study of 29 participants. J Atten Disord. 2008;12(3):218–26.
Salakari A, Virta M, Gronroos N, Chydenius E, Partinen M, Vataja R, et al. Cognitive-behaviorally-oriented group rehabilitation of adults with ADHD: results of a 6-month follow-up. J Atten Disord. 2010;13(5):516–23.
Hesslinger B, Tebartz van Elst L, Nyberg E, Dykierek P, Richter H, Berner M, et al. Psychotherapy of attention deficit hyperactivity disorder in adults—a pilot study using a structured skills training program. Eur Arch Psychiatry Clin Neurosci. 2002;252(4):177–84.
Fleming AP, McMahon RJ, Moran LR, Peterson AP, Dreessen A. Pilot randomized controlled trial of dialectical behavior therapy group skills training for ADHD among college students. J Atten Disord. 2015;19(3):260–71.
Philipsen A, Richter H, Peters J, Alm B, Sobanski E, Colla M, et al. Structured group psychotherapy in adults with attention deficit hyperactivity disorder: results of an open multicentre study. J Nerv Ment Dis. 2007;195(12):1013–9.
Zylowska L, Ackerman DL, Yang MH, Futrell JL, Horton NL, Hale TS, et al. Mindfulness meditation training in adults and adolescents with ADHD: a feasibility study. J Atten Disord. 2008;11(6):737–46.
Mitchell JT, McIntyre EM, English JS, Dennis MF, Beckham JC, Kollins SH. A pilot trial of mindfulness meditation training for attention-deficit/hyperactivity disorder in adulthood: impact on core symptoms, executive functioning, and emotion dysregulation. J Atten Disord. 2013;1177(/1087054713513328):10.
Cohen J. Statistical power analysis for the behavioral sciences. 2nd ed. Lawrence Earlbaum Associates: Hillsdale; 1988.
Prince JB, Morrison NR, Wilens TE. Psychosocial treatment of ADHD in adults. In: Adler LA, Spencer TJ, Wilens TE, editors. Attention-deficit hyperactivity disorder in adults and children. Cambridge: Cambridge University Press; 2015. p. 276–97.
Marchant BK, Reimherr FW, Halls C, Williams ED, Strong RE. OROS methylphenidate in the treatment of adults with ADHD: a 6-month, open-label, follow-up study. Ann Clin Psychiatry. 2010;22(3):196–204.
Marchant BK, Reimherr FW, Robison RJ, Olsen JL, Kondo DG. Methylphenidate transdermal system in adult ADHD and impact on emotional and oppositional symptoms. J Atten Disord. 2011;15(4):295–304.
Wender PH, Reimherr FW, Marchant BK, Sanford ME, Czajkowski LA, Tomb DA. A one year trial of methylphenidate in the treatment of ADHD. J Atten Disord. 2011;15(1):36–45.
Retz W, Rosler M, Ose C, Scherag A, Alm B, Philipsen A, et al. Multiscale assessment of treatment efficacy in adults with ADHD: a randomized placebo-controlled, multi-centre study with extended-release methylphenidate. World J Biol Psychiatry. 2012;13(1):48–59.
Adler LA, Dirks B, Deas PF, Raychaudhuri A, Dauphin MR, Lasser RA, et al. Lisdexamfetamine dimesylate in adults with attention-deficit/ hyperactivity disorder who report clinically significant impairment in executive function: results from a randomized, double-blind, placebo-controlled study. J Clin Psychiatry. 2013;74(07):694–702.
Adler LA, Alperin S, Leon T, Faraone S. Clinical effects of lisdexamfetamine and mixed amphetamine salts immediate release in adult ADHD: results of a crossover design clinical trial. Postgrad Med. 2014;126(5):17–24.
Michelson D, Adler L, Spencer T, Reimherr FW, West SA, Allen AJ, et al. Atomoxetine in adults with ADHD: two randomized, placebo-controlled studies. Biol Psychiatry. 2003;53(2):112–20.
Marchant BK, Reimherr FW, Halls C, Williams ED, Strong RE, Kondo D, et al. Long-term open-label response to atomoxetine in adult ADHD: influence of sex, emotional dysregulation, and double-blind response to atomoxetine. Atten Defic Hyperact Disord. 2011;3(3):237–44.
Brown TE, Holdnack J, Saylor K, Adler L, Spencer T, Williams DW, et al. Effect of atomoxetine on executive function impairments in adults with ADHD. J Atten Disord. 2011;15(2):130–8.
Adler L, Tanaka Y, Williams D, Trzepacz PT, Goto T, Allen AJ, et al. Executive function in adults with attention-deficit/hyperactivity disorder during treatment with atomoxetine in a randomized, placebo-controlled, withdrawal study. J Clin Psychopharmacol. 2014;34(4):461–6.
Adler LA, Solanto M, Escobar R, Lipsius S, Upadhyaya H. Executive functioning outcomes over 6 months of atomoxetine for adults with ADHD: relationship to maintenance of response and relapse over the subsequent 6 months after treatment. J Atten Disord. 2016.
Adler LA, Clemow DB, Williams DW, Durell TM. Atomoxetine effects on executive function as measured by the BRIEF-A in young adults with ADHD: a randomized, double-blind, placebo-controlled study. PLoS One. 2014;9(8):e104175.
Asherson P, Stes S, Nilsson Markhed M, Berggren L, Svanborg P, Kutzelnigg A, et al. The effects of atomoxetine on emotional control in adults with ADHD: an integrated analysis of multicenter studies. Eur Psychiatry. 2015;30(4):511–20.
Wender PH, Reimherr FW. Bupropion treatment of attention-deficit hyperactivity disorder in adults. Am J Psychiatry. 1990;147(8):1018–20.
Hedges D, Reimherr FW, Rogers A, Strong R, Wender PH. An open trial of venlafaxine in adult patients with attention deficit hyperactivity disorder. Psychopharmacol Bull. 1995;31(4):779–83.
Rostain AL, Ramsay JR. A combined treatment approach for adults with ADHD—results of an open study of 43 patients. J Atten Disord. 2006;10(2):150–9.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2018 Springer International Publishing AG
About this chapter
Cite this chapter
Silverstein, M.J., Alperin, S., Hochstein, Y., Adler, L.A. (2018). Moody Adults with ADHD. In: Daviss, W. (eds) Moodiness in ADHD. Springer, Cham. https://doi.org/10.1007/978-3-319-64251-2_11
Download citation
DOI: https://doi.org/10.1007/978-3-319-64251-2_11
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-64250-5
Online ISBN: 978-3-319-64251-2
eBook Packages: MedicineMedicine (R0)