The Demand-Control Model Highlights and Future Directions: The Stress-Disequilibrium Theory

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The Demand-Control Model Highlights and Future Directions: The Stress-Disequilibrium Theory Robert Karasek, Ph.D., Work Environment Department, University of Massachusetts Lowell, USA second Danske Stressforskningskonference, Copenhagen, November 2005

The Demand/Control Model ... Mental Demands Low High Hypo. #2 Motivation, Active Learning Active Lo Strain Lo Strain Lo Strain Decision Latitude Hypo. #1 Illness Risk Passive Hi Strain Low

FIGURE 1: The STRESS Model NEG. EMOT, (+) STRESSORS Job DEMANDS Demography Personality Job Insecurity INDIVID.DIFF. Work Phys Dem. Ceaseless DISEASE Family Demands

FIGURE 2: The Stress Models: Demand/Control - STRAIN MODERATORS Job CONTROL Job Social Support (- - ) NEG. EMOT, (+) STRESSORS STRAIN Job DEMANDS S Demograph Personality Job Insccurity INDIVID.DIFF. Work Phys. Request CHRONIC DISEASE Family Demands

FIGURE 3: The Stress Models: Full D/C Model: Strain/ACTIVE BEHAVIOR MODERATORS Job CONTROL ACTIVE Job Social Support (+) (+) (- - ) NEG. EMOT, (+) STRAIN STRESSORS Job DEMANDS S INDIVID.DIFF. Work Insccurity Demograph Personality Job Phys. Request CHRONIC DISEASE Family Demands

CANONICAL CORRELATION ANALYSIS Swedish Standard of Living Study 1968Employed Males Age 18 – 66 (n = 1865)

Epidemiological Evidence for Three Work-Related Chronic Disease Conditions Belkic et al (2004): surveys of 46 CVD Studies Scand J Work Environ Health, 30;2:85-128 "… notwithstanding the solid, steady proof of a relationship between presentation to occupation strain and CVD , … numerous different components of causal surmising, particularily natural credibility, have been appeared in this audit to bolster the conclusion that employment strain is to be sure a noteworthy CVD chance element … "(p 117) Bongers et al (2002): 28 musculoskeletal disorders(MSDs) studies Am J Ind Medicine, 41:315-342 "… It was reasoned that dull work, high-saw workload, a period weight are identified with musculoskeletal side effects. The information additionally propose that likewise low control at work and poor social support might be related to the improvement of the sickness. Just about 10 years after the fact and with a more orderly way to deal with the inspecting procedure, the conclusion are comparable with the exemption that no support was found for the part of tedious work… and occupation requests all the more circumspectly interpreted"(p 329) Van der Doef and Maes (1999): audit of 63 mental strain thinks about Work & Stress , 13;2:87-114 28 out of 41 studies on General Psychological prosperity bolstered DC display 28 out of 42 studies on Job-related prosperity upheld DC show

D-C Model: Boundaries of Theory INCONSISTENCIES? - MODEL THE FULL SYSTEM: 1. Relaxation/Political Activity'70's: Urban, utilized 2. National work relations accepted 1970's - Now: worldwide neo-liberal economy 3. Malady models: CHD, Mental Distress a. etiological model: moderate versus quick "development" b. MSD: restricted difference work tests 4. Psychosocial clarification of social expenses and advantages: Beyond monetary analytics

Convergence of Job Characteristics in Global Economy: . Prove from JCQ worldwide near research on scales for employment control, requests, support, and uncertainty: 1. Awesome likeness of means and standard deviations - in full occupation range tests crosswise over nations (not in class subgroups) 2. Between-occupation scale change significantly more prominent than between-nation difference -(full occupations range tests) 3. Great closeness of relationships between's JCQ scales (control, request, bolster, and so forth.) crosswise over nations -aside from mental requests 4. Awesome comparability of Cronback alpha measurements crosswise over nations (full word related range, not inside class subgroups) 5. Comparable JCQ operation in Formal Sector & Informal Sector (in creating nations: semi-urban Brazil)

Between word related class varieties of control and requests by sexual orientation

A Second Social Class Perspective: PSYCHOSOCIAL JOB CHARACTERISTICS - VS. Pay I II

Occupational class slope and Job strain pivot in JACE-JCQ information (Choi and Karasek et al., 2004)

Stress, Class, Low Control & Disease Increasingly reverse social class inclination in wellbeing Path I : Low status, Absolute Deprivation Path II : Social disparity, Relative Deprivation Stress-related dreariness in view of thoughtful over-excitement from psychosocial requests can't clarify it Higher business related mental requests at high status Relative Inequality may not clarify quite a bit of it Substantial low control-related horribleness even in generally salary adjusted social orders A STRESS-DISEASE MODEL BASED ON LOW CONTROL (Absolute) … Supplements material hardship, mental-stack stress, and status imbalance

Job strain, Cardiovascular Disease and CVD Risk Factors (Landsbergis, 1/1999) ● 72 concentrates distributed in the vicinity of 1981 and 1998 ● 36 investigations of CVD (+2 of all-cause mortality) ● 25 discovered huge relationship with employment strain ● 11 of 19 accomplice considers had critical affiliations ● Low employment choice scope : some positive relationship in 35 of 46 studies ● High Job requests : some positive relationship in 14 of 40 studies converse relationship in 5 late reviews ● Low social support : positive in 5 of 13 studies

Definitions of Work and Control-Internal and External A. Theory #1: √  Work External Stressors, Allostatic Challenge Work Internal Homeostatic Regulation Allostatic Regulation B. Theory #2: ? Control External Control Internal External Environment Internal Environment

Back to the Reptiles?

From the first Law to the second Law .. To start with LAW OF THERMODYNAMICS = Conservation of Energy: Count calories-> Run around track - >Loose weight ? - To Conquer our Exhaustion in the Global Economy, might we be able to simply Eat More Food - ? SECOND LAW OF THERMODYNAMICS = Limits on Ordering limit

ORDERED AND DISORDERED ENERGY: - Definitions: 1. Work is requested vitality with couple of degrees of opportunity . A case is the steam motor's cylinder : all vitality is diverted to one heading of movement which is unsurprising and usable (another case, the speeding projectile). 2. Disarranged vitality - warm - has numerous arbitrary degrees-of-flexibility: It's vitality is undirectable , and less valuable to do work. 3. The disorder segment of vitality is called Entropy . Its inverse, a requesting limit with respect to vitality, is now and then called Neg-Entropy (which gets to be Work when vitality is "added" - generally). 4. second Law of Thermodynamics yields Efficiency Criteria which restrain the measure of Heat Energy that can be moved into Work as valuable activity (ordinary: 25%). 5. In science much Work exists as Stored Energy of Chemical Bonds.

UNCONTROLLED DEMANDS The Dual Goal of CNS Regulation: External Action & Internal Control Protecting the Stability of The Internal Homeostatic Regulatory Environment CNS Path II. Homeostatic Regulation Limits: 1. Blood O 2: :1<x<2 2. Body Temp: 3. Blood CO 2 4. Blood pH: 1<y<2 5. … @R. Karasek 10-02, Unpublished Autonomic NS, and Hormone Regulat. Environ-mental Demand Personal Adaptive Action Allostatic Regulatation 1. Adrenaline 2. Metabolic 3. Resting 4. Noradrenaline Path I. Utilizing Allostatic Resources I. Outside ALLOSTATIC CHALLENGES II. Inside HOMEOSTATIC CHALLENGES

"A Central Controller" is expected to adjust Stress Theory to Thermodynamics. Complex life forms change their limit conditions (streams), to look after equilibria. This requires two new streams of Neg-Entropy: Flow 3 and Flow 4 Flow 1 Environment Neg-Entropy Flow 1 Environment System Flow 2 System Neg-Entropy Flow 4 = ? Neg-Entropy Flow 3 Neg-Entropy Flow 2 Controller The Stress Model: System, Environment & Controller: Adapting the Standard Thermodynamic Model Figure 1: Entropy Flows - Standard Thermodynamic Model Figure 1b: Entropy Flows - Extended Stress Theory with Controller

Table 11/5/1 Ashby, R move #A #B #C #1 f k #2 k e f D move #3 m k a #4 b #5 c q c #6 h m Ashby's Theory of Requisite Variety Cybernetics, 1956 The objective of Regulation [is to] hinder the stream of assortment [from the living being's environment] which would bother its inner factors. •"The idealize indoor regulator would be the one that, disregarding aggravation, kept the temperature consistent at the coveted level." The Law of Requisite Variety: Only assortment in the Regulator (R) can drive down assortment in the Environment (D) … Only assortment can pulverize variety." Ashby's Proof is a legitimately broad amusement hypothesis case: •'s R will probably protect choice of a particular fancied arrangement of results (= k ). D moves first. • Response sets (R,D) : (1,C) (2,A) (3,B) (9,A) Outcome of amusement = k l Only assortment in R's moves can compel down the assortment in the results.

1 A B C 2 3 Action-Possibilities Climbing up - and Moving Down: the Neg-Entropy Hill Ashby's Regulator: "Etch-a-Sketch" CNS: "Central Controller" Environmental difficulties General Energy External Work Light  Photo-Synthesis  Glucose, Monomers Stored Energy Creates 'Imperatives " Physiological Sub-frameworks' Actions Coordinated Creating Ordering Capacity from Random Energy - the "Neg-Entropy Pump" -Flow # 4 Using Up Ordering Capacity-Facilitating External Work - Flow # 3 Flow # 2 Flow # 1

Core of the New Hypothesis: High Level Control Capacity is made -by means of Multi-Level Structure: A "Negative-Entropy Pump" a. In the first place, Random Energy at a Low Structural Level is changed into Wor