Deze artikelen (deel I en deel II) bevatten een overzicht van de literatuur van de laatste vijftien jaren over psychomotorische stoornissen bij depressieve patiënten, zoals ze gemeten worden met behulp van de volgende meetmethoden:

1. 1. observatieschalen (deel I);

2. 2. de meting en de analyse van specifiek non-verbaal gedrag (deel I);

3. 3. spraakonderzoek (deel I);

4. 4. (keuze) reactietijdmetingen (deel II);

5. 5. metingen van grove motoriek (deel II);

6. 6. onderzoek van fijne motoriek (deel II).

De onderzoeksresultaten warden per methode samengevat. Onderzocht wordt of (a) bij depressieve patiënten een vertraging vastgesteld werd, (b) waaruil deze bestond, (c) welke de aard van de vertraging was, (d) of er correlaties gevonden werden met andere meetmethodes, en (e) welke effecten van behandeling er werden gemeten.

This review (part I and II) contains an overview of the literature of the past fifteen years over psychomotor retardation in depressed patients, as measured by the following methods:

1. observation scales (part I);

2. observation, coding and analysis of specific nonverbal behaviour (part I);

3. speech research (part I);

4. (choice) reaction time tasks (part II);

5. analysis of gross motor activity (part II);

6. of fine motor behaviour (part II).

In each section the results of the different studies are summarized and discussed, in order to answer the following questions: (a) did the depressed patients show any retardation?, (b) how did this retardation manifest itself?, (c) what was the nature of the retardation?, (d) were there any correlations with the results of other methods? and (e) what were the effects of antidepressive treatment?

Within the NIMH Research Domain Criteria (RDoC) framework, dimensions of behavior are investigated across diagnoses with the goal of developing a better understanding of their underlying neural substrates. Currently, this framework includes five domains: cognitive, social, arousal/regulatory, negative, and positive valence systems. We argue that the inclusion of a motor systems domain is sorely needed as well. Independent of medication, distinct areas of motor dysfunction (e.g. motor planning/inhibition/learning/coordination, involuntary movements) commonly appear across a number of mental disorders (e.g. schizophrenia, bipolar disorder, autism, attention deficit hyperactivity disorder, Alzheimer's disease, depression) as well as neurological disorders accompanied by significant psychological symptoms (e.g. Parkinson's disease). In addition, motor systems are amenable to study across multiple levels of analysis from the cellular molecular level focusing on cytoarchitechtonics and neurotransmitter systems, to networks and circuits measured using neuroimaging, and finally at the level of overt behavioral performance. Critically, the neural systems associated with motor performance have been relatively well defined, and different circuits have been linked to distinct aspects of motor behavior. As such, they may also be differentially associated with symptoms and motor dysfunction across diagnoses, and be uniquely informative about underlying etiology. Importantly, motor signs can change across stages of illness; they are also often present in the prodromal phases of disease and closely linked with course, suggesting that these behaviors represent a core feature reflective of pathogenic processes. The inclusion of a motor domain would allow researchers to better understand psychopathology more broadly, and may also reveal important contributions to disease processes across diagnoses.

Psychomotor slowing has been documented in depression. The digital Clock Drawing Test (dCDT) provides: (i) a novel technique to assess both cognitive and motor aspects of psychomotor speed within the same task and (ii) the potential to uncover subtleties of behavior not previously detected with non-digitized modes of data collection. Using digitized pen technology in 106 participants grouped by Age (younger/older) and Affect (euthymic/unmedicated depressed), we recorded cognitive and motor output by capturing how the clock is drawn rather than focusing on the final product. We divided time to completion (TTC) for Command and Copy conditions of the dCDT into metrics of percent of drawing (%Ink) versus non-drawing (%Think) time. We also obtained composite Z-scores of cognition, including attention/information processing (AIP), to explore associations of %Ink and %Think times to cognitive and motor performance. Despite equivalent TTC, %Ink and %Think Command times (Copy n.s.) were significant (AgeXAffect interaction: p=.03)—younger depressed spent a smaller proportion of time drawing relative to thinking compared to the older depressed group. Command %Think time negatively correlated with AIP in the older depressed group (r=−.46; p=.02). Copy %Think time negatively correlated with AIP in the younger depressed (r=−.47; p=.03) and older euthymic groups (r=−.51; p=.01). The dCDT differentiated aspects of psychomotor slowing in depression regardless of age, while dCDT/cognitive associates for younger adults with depression mimicked patterns of older euthymics. (JINS, 2014, 20, 1–9)