Maarten W. Bos

Post-Doctoral Fellow of Business Administration

Maarten Bos is a Post-Doctoral Research Fellow of Business Administration in the Negotiation, Organizations & Markets Unit at the Harvard Business School. He holds a PhD in Psychology from Radboud University Nijmegen and a BA and MS in Psychology from the University of Amsterdam.

His work has been published in a number of leading academic journals, including Science, Psychological Science, Journal of Experimental Social Psychology, and Journal of Consumer Psychology and has been covered in media outlets around the world, including the United States, the United Kingdom, the Netherlands, Turkey, India, Pakistan, South Korea, and China. His article, "A Counter-Intuitive Approach to Making Complex Decisions" ranked among the most popular blog articles on the Harvard Business Review website in 2011. In 2012, he was interviewed for HBS Working Knowledge, which resulted in the piece "The Unconscious Executive".
Recently, an interview with CNN resulted in a contribution to their 'Route to the Top'. 

At HBS, he taught the doctoral course Behavioral Approaches to Decision Making, and co-taught lectures in Professor Amy Cuddy's second-year MBA class, Power & Influence.

When he is not publishing and receiving media attention, he enjoys large quantities of good food, music, and motorcycles. 

 

Journal Articles

  1. Unconscious Thought Reduces Intrusion Development: A Replication and Extension

    Background and Objectives: Intrusive images after a traumatic event, a hallmark feature of post-traumatic stress disorder, are suggested to develop because the trauma memory is disorganized and not integrated into autobiographical memory. Unconscious Thought Theory predicts that information can be conceptually organized after a period of unconscious thought (UT), more so than after conscious thought (CT). We aimed to test the hypothesis that UT decreases intrusions and increases conceptual organization in memory. Methods: Participants were shown a stressful film and were required to perform an UT task, a CT task, or a distraction task. Intrusions of the film, intrusion qualities, and sequence memory were measured afterwards. Results: We confirmed our hypothesis that UT (versus CT or mere distraction) leads to fewer intrusions, thereby replicating earlier research. Contrary to prediction, we found no difference between the conditions on sequence memory. In addition, conscious thought appeared to increase intrusion nowness and arousal. Limitations: The analogue design and healthy participant sample prevent from generalizing results to other populations. Intrusion frequency and qualities were assessed immediately after the film thereby prohibiting us from drawing conclusions about any long-term effects. Conclusions: Engaging in unconscious thought after a stressful film can reduce intrusion frequency. This has potential implications for clinical interventions to prevent initial stress symptoms. The underlying mechanism remains unclear for now and provides an avenue for future research.

    Citation:

    Krans, Julie, Dorte Janecko, and Maarten W. Bos. "Unconscious Thought Reduces Intrusion Development: A Replication and Extension." Journal of Behavior Therapy and Experimental Psychiatry 44, no. 2 (June 2013): 179–185.
  2. Food for Thought? Trust Your Unconscious When Energy Is Low

    Recent studies show that a period of unconscious thought can help when making complex decisions. Under some circumstances, unconscious thought improves decisions even more than conscious thought. Executive functioning depends on energy provided by glucose, and we know from previous research that the performance of various conscious processes deteriorates when energy is low. Unconscious processes require less energy and may operate unhampered when energy is low. Therefore, we propose that whereas low blood glucose levels impair conscious thought, this is not the same for unconscious thought. An experiment, where we manipulated blood glucose levels, indicated that indeed, when making decisions, the unconscious can best be trusted when blood glucose levels are low, whereas conscious deliberation yields the best results when blood glucose levels are elevated.

    Keywords: Cognition and Thinking; Decision Making;

    Citation:

    Bos, Maarten, Ap Dijksterhuis, and Rick B. Van Baaren. "Food for Thought? Trust Your Unconscious When Energy Is Low." Journal of Neuroscience, Psychology and Economics 5, no. 2 (May 2012): 124–130.
  3. Good Morning Creativity: Task Reactivation During Sleep Enhances Beneficial Effect of Sleep on Creative Performance

    Both scientists and artists have suggested that sleep facilitates creativity, and this idea has received substantial empirical support. In the current study, we investigate whether one can actively enhance the beneficial effect of sleep on creativity by covertly reactivating the creativity task during sleep. Individuals' creative performance was compared after three different conditions: sleep-with-conditioned-odor; sleep-with-control-odor; or sleep-with-no-odor. In the evening prior to sleep, all participants were presented with a problem that required a creative solution. In the two-odor conditions, a hidden scent diffuser spread an odor while the problem was presented. In the sleep-with-conditioned-odor condition, task reactivation during sleep was induced by means of the odor that was also presented while participants were informed about the problem. In the sleep-with-control-odor condition, participants were exposed to a different odor during sleep than the one diffused during problem presentation. In the no-odor condition, no odor was presented. After a night of sleep with the conditioned odor, participants were found to be (i) more creative and (ii) better able to select their most creative idea than participants who had been exposed to a control odor or no odor while sleeping. These findings suggest that we do not have to passively wait until we are hit by our creative muse while sleeping. Task reactivation during sleep can actively trigger creativity-related processes during sleep and thereby boost the beneficial effect of sleep on creativity.

    Keywords: Creativity; Performance;

    Citation:

    Ritter, Simone M., Madelijn Strick, Maarten Bos, Rick B. Van Baaren, and Ap Dijksterhuis. "Good Morning Creativity: Task Reactivation During Sleep Enhances Beneficial Effect of Sleep on Creative Performance." Journal of Sleep Research 21, no. 6 (December 2012): 643–647.
  4. To Think or Not to Think about Trauma? An Experimental Investigation into Unconscious Thought and Intrusion Development

    The present study tested whether unconscious thought (versus conscious thought) would reduce frequency of intrusions from an analogue trauma film. Participants viewed a distressing film and were subsequently instructed to think about the film deliberately (conscious thought), to perform a demanding task while knowing that the film information was important later on the experiment (unconscious thought), or to perform the task while believing the experiment had ended (control condition). Afterwards, sequence memory and intrusions of the film were measured. In line with predictions, the results showed significant lower intrusion frequency in the unconscious thought condition compared to both conscious thought and mere distraction. As there were no differences in sequence memory for the film, it remains unclear what mechanism was responsible for this effect. These results encourage further research into a new and exciting area.

    Keywords: Cognition and Thinking; Growth and Development;

    Citation:

    Krans, Julie, and Maarten W. Bos. "To Think or Not to Think about Trauma? An Experimental Investigation into Unconscious Thought and Intrusion Development." Journal of Experimental Psychopathology 3, no. 2 (2012): 310–321.
  5. The Benefits of 'Sleeping on Things': Unconscious Thought Leads to Automatic Weighting

    We tested and confirmed the hypothesis that unconscious thought leads to an automatic weighting process whereby important decision attributes receive more weight, and unimportant decision attributes receive less weight. In three experiments, participants chose between cars with few important positive attributes and many unimportant negative attributes ("Quality cars"), and cars with many unimportant positive attributes and few important negative attributes ("Frequency cars"). In all experiments, unconscious thinkers showed a stronger preference for Quality cars than immediate decision makers, showing that unconscious thought indeed evokes an automatic weighting process. An alternative explanation is refuted and implications are discussed.

    Keywords: Decisions; Decision Choices and Conditions; Cognition and Thinking; Quality;

    Citation:

    Bos, Maarten W., Ap Dijksterhuis, and Rick B. Van Baaren. "The Benefits of 'Sleeping on Things': Unconscious Thought Leads to Automatic Weighting." Journal of Consumer Psychology 21, no. 1 (January 2011): 4–8.
  6. Unconscious Thought Works Bottom-up and Conscious Thought Works Top-down When Forming an Impression

    We tested and found supportive evidence for one of the principles of Unconscious Thought Theory (UTT); namely, that unconscious thought is a bottom-up process, whereas conscious thought is a top-down process. In two experiments on impression formation, participants read behavioral information about a fictitious person after a stereotype had been activated. We found that unconscious thinkers formed an impression unbiased by the stereotype, suggesting a bottom-up strategy, whereas conscious thinkers relied on the stereotype, suggesting a top-down strategy. That is, when thinking consciously, participants relied more on stereotype-congruent information and suppressed stereotype-incongruent information. Implications for impression formation are discussed.

    Keywords: Cognition and Thinking; Theory; Management Practices and Processes; Behavior; Prejudice and Bias; Strategy; Information;

    Citation:

    Bos, Maarten W., and Ap Dijksterhuis. "Unconscious Thought Works Bottom-up and Conscious Thought Works Top-down When Forming an Impression." Social Cognition 29, no. 6 (2011): 727–737.
  7. A Meta-analysis on Unconscious Thought Effects

    A meta-analysis was performed on the unconscious thought effect (UTE). All available published and unpublished data on unconscious thought were included. Our aims were to provide a statistically robust estimate of the effect size of the UTE, to identify significant moderators, and to discuss possible underlying processes of the UTE. To assess the UTE, performance of participants thinking unconsciously was compared to participants thinking consciously, and to immediate decision makers. Across a total of 92 studies, the overall aggregated effect size was g = .224, with a 95% confidence interval from .145 to .303. This result provides strong support for the existence of the UTE. However, as estimated from a random-effects model, about 66% of the variance in effect sizes was attributable to systematic differences between studies. This result indicates that although the UTE is a real effect, it does not always occur. Several moderators were identified that help to explain the mixed results across various studies. The findings are discussed with regard to the boundary conditions and potential underlying processes of the UTE.

    Keywords: Mathematical Methods; Cognition and Thinking; Management Practices and Processes; Performance;

    Citation:

    Strick, Madelijn, Ap Dijksterhuis, Maarten W. Bos, Aukje Sjoerdsma, Rick B. Van Baaren, and Loran F. Nordgren. "A Meta-analysis on Unconscious Thought Effects." Social Cognition 29, no. 6 (2011): 738–762.
  8. The Best of Both Worlds: Integrating Conscious and Unconscious Thought Best Solves Complex Decisions

    Two studies address the debate over whether conscious or unconscious mental processes best handle complex decisions. According to Unconscious Thought Theory (Dijksterhuis & Nordgren, 2006), both modes of thinking have particular advantages: conscious thought can follow strict rules, whereas unconscious thought is better suited for integrating numerous decision attributes. Because most complex decisions require both adherence to precise rules and the aggregation of information, we hypothesized that complex decisions can best be made by engaging in periods of both conscious and unconscious thought. In both studies we found that the sequential integration of conscious and unconscious thought solved complex choices better than conscious or unconscious thought alone. In Study 2 we examined whether the sequential order of the integration condition matters. In line with our prediction, we found that integration worked best when unconscious thought followed conscious thought.

    Keywords: Forecasting and Prediction; Values and Beliefs; Information; Knowledge Management; Management Skills; Management Style; Measurement and Metrics; Success; Research; Cognition and Thinking; Personal Characteristics; Perception;

    Citation:

    Nordgren, Loran F., Maarten W. Bos, and Ap Dijksterhuis. "The Best of Both Worlds: Integrating Conscious and Unconscious Thought Best Solves Complex Decisions." Journal of Experimental Social Psychology 47, no. 2 (2011): 509–511.
  9. Predicting Soccer Matches after Unconscious and Conscious Thought as a Function of Expertise

    Keywords: Cognition and Thinking;

    Citation:

    Dijksterhuis, Ap, Maarten W. Bos, Andries Van der Leij, and Rick B. Van Baaren. "Predicting Soccer Matches after Unconscious and Conscious Thought as a Function of Expertise." Psychological Science 20, no. 11 (2009): 1381–1387.
  10. On the Goal-dependency of Unconscious Thought

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., Ap Dijksterhuis, and Rick B. Van Baaren. "On the Goal-dependency of Unconscious Thought." Journal of Experimental Social Psychology 44, no. 4 (2008): 1114–1120.
  11. On Making the Right Choice: The Deliberation-without-attention Effect

    Keywords: Decision Choices and Conditions;

    Citation:

    Dijksterhuis, Ap, Maarten W. Bos, Loran F Nordgren, and Rick B. Van Baaren. "On Making the Right Choice: The Deliberation-without-attention Effect." Science (Weekly) 311, no. 5763 (February 2006): 1005–1007.
  12. Making Choices Without Deliberating

    Keywords: Decision Choices and Conditions;

    Citation:

    Dijksterhuis, Ap, Maarten W. Bos, Loran F Nordgren, and Rick B. Van Baaren. "Making Choices Without Deliberating." Science (Weekly) 312, no. 5779 (2006): 1472.
  13. Complex Choices Better made Unconsciously?

    Keywords: Decision Choices and Conditions;

    Citation:

    Dijksterhuis, Ap, Maarten W. Bos, Loran F Nordgren, and Rick B. Van Baaren. "Complex Choices Better made Unconsciously?" Science (Weekly) 313, no. 5788 (2006): 760–761.

Book Chapters

  1. Prolonged Thought: Proposing Type 3 Processing

    Citation:

    Dijksterhuis, Ap, Madelijn Strick, Maarten W. Bos, and Loran F. Nordgren. "Prolonged Thought: Proposing Type 3 Processing." In Dual Process Theories of the Social Mind, by Jeffrey W. Sherman, Bertram Gawronski, and Yaacov Trope. New York: Guilford Press, In Press.
  2. Self-knowledge, Unconscious Thought, and Decision Making

    Keywords: Perception; Decision Making; Personal Characteristics;

    Citation:

    Bos, Maarten W., and Ap Dijksterhuis. "Self-knowledge, Unconscious Thought, and Decision Making." In Handbook of Self-knowledge, edited by Simine Vazire, and Timothy D. Wilson. Guilford Press, 2012.
  3. The Rational Unconscious: Conscious versus Unconscious Thought in Complex Consumer Choice

    Keywords: Cognition and Thinking; Perception; Consumer Behavior; Complexity; Decision Choices and Conditions;

    Citation:

    Dijksterhuis, Ap, Rick B. Van Baaren, Karin C. A. Bongers, Maarten W. Bos, Matthijs L. Van Leeuwen, and Andries R. Van der Leij. "The Rational Unconscious: Conscious versus Unconscious Thought in Complex Consumer Choice." Chap. 4 in Social Psychology of Consumer Behavior, 89–108. New York, U.K.: Psychology Press, 2009.

Working Papers

  1. iPosture: The Size of Electronic Consumer Devices Affects Our Behavior

    We examined whether incidental body posture, prompted by working on electronic devices of different sizes, affects power-related behaviors. Grounded in research showing that adopting expansive body postures increases psychological power, we hypothesized that working on larger devices, which forces people to physically expand, causes users to behave more assertively. Participants were randomly assigned to interact with one of four electronic devices that varied in size: an iPod Touch, an iPad, a MacBook Pro (laptop computer), or an iMac (desktop computer). As hypothesized, compared to participants working on larger devices (e.g., an iMac), participants who worked on smaller devices (e.g., an iPad) behaved less assertively—waiting longer to interrupt an experimenter who had made them wait, or not interrupting at all.

    Citation:

    Bos, Maarten W., and Amy J.C. Cuddy. "iPosture: The Size of Electronic Consumer Devices Affects Our Behavior." Harvard Business School Working Paper, No. 13–097, May 2013.

Cases and Teaching Materials

  1. OPOWER: Increasing Energy Efficiency through Normative Influence (A)

    The case profiles OPOWER, an energy efficiency software company that applies Cialdini's principles of social influence to successfully encourage consumers to reduce their energy usage. OPOWER was co-founded in 2008 by two young Harvard graduates, Dan Yates and Alex Laskey, who were inspired by Robert Cialdini's behavioral science research showing that people's normative beliefs - and messaging tailored to those beliefs - had a powerful and measurable impact on their energy-conserving behaviors. Yates and Laskey redesigned the home energy bill to include normative messaging, including feedback on how consumers' energy usage compares to their neighbors' usage. Through early trials of the program, the electrical utilities began seeing 1.5% to 3.5% savings in energy usage, almost immediately. After the rapid success of OPOWER's first three years, Yates and Laskey wondered whether their approach would produce sustainable results: what strategy should they pursue to ensure that consumers continue to read and respond to the normative messaging in the "Energy Bill 2.0"?

    Keywords: Mathematical Methods; Software; Attitudes; Entrepreneurship; Energy Conservation; Power and Influence; Growth and Development Strategy; Energy Industry; United States;

    Citation:

    Cuddy, Amy J.C., Kyle Todd Doherty, and Maarten W. Bos. "OPOWER: Increasing Energy Efficiency through Normative Influence (A)." Harvard Business School Case 911-016, January 2012. (Revised from original September 2010 version.)
  2. OPOWER: Increasing Energy Efficiency through Normative Influence (B)

    The case profiles OPOWER, an energy efficiency software company that applies Cialdini's principles of social influence to successfully encourage consumers to reduce their energy usage. OPOWER was co-founded in 2008 by two young Harvard graduates, Dan Yates and Alex Laskey, who were inspired by Robert Cialdini's behavioral science research showing that people's normative beliefs - and messaging tailored to those beliefs - had a powerful and measurable impact on their energy-conserving behaviors. Yates and Laskey redesigned the home energy bill to include normative messaging, including feedback on how consumers' energy usage compares to their neighbors' usage. Through early trials of the program, the electrical utilities began seeing 1.5% to 3.5% savings in energy usage, almost immediately. After the rapid success of OPOWER's first three years, Yates and Laskey wondered whether their approach would produce sustainable results: what strategy should they pursue to ensure that consumers continue to read and respond to the normative messaging in the "Energy Bill 2.0"?

    Keywords: Energy Conservation;

    Citation:

    Bos, Maarten W., Amy J.C. Cuddy, and Kyle Todd Doherty. "OPOWER: Increasing Energy Efficiency through Normative Influence (B)." Harvard Business School Supplement 911-061, January 2012. (Revised from original May 2011 version.)

Presentations

  1. Using Conscious and Unconscious Thought in Decision Making

    Keywords: Decision Making;

    Citation:

    Bos, Maarten W., Loran F. Nordgren, and Ap Dijksterhuis. "Using Conscious and Unconscious Thought in Decision Making." Paper presented at the 16th European Association of Social Psychology General Meeting, Stockholm, Sweden, July 2011.
  2. Scarcity Is More Than a Social Proof Effect

    Citation:

    Bos, Maarten W., Ap Dijksterhuis, and Rick B. Van Baaren. "Scarcity Is More Than a Social Proof Effect." Paper presented at the 12th Society for Personality and Social Psychology Annual Meeting, San Antonio, TX, January 27–29, 2011.
  3. Good Morning Creativity: Odor Cue Triggers Creativity-related Processes during Sleep

    Keywords: Creativity;

    Citation:

    Ritter, Simone M., Madelijn Strick, Maarten W. Bos, Rick B. Van Baaren, and Ap Dijksterhuis. "Good Morning Creativity: Odor Cue Triggers Creativity-related Processes during Sleep." Paper presented at the 12th Society for Personality and Social Psychology Annual Meeting, San Antonio, TX, January 27–29, 2011.
  4. Resisting the Industry

    Citation:

    Bos, Maarten, and Joost B.C. Mertens. "Resisting the Industry." Paper presented at the Psychiatrist Society Annual Meeting, The Netherlands, January 2011.
  5. Unconscious Thought, A Brute Force?

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., Ap Dijksterhuis, and Rick B. Van Baaren. "Unconscious Thought, A Brute Force?" Paper presented at the ESCON Transfer of Knowledge Conference, European Social Cognition Network (ESCON), Gothenburg, Sweden, September 2010.
  6. Unconscious Thought Excels when Challenged: Unconscious Thought Does Not Choke under Pressure

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., Ap Dijksterhuis, and Rick B. Van Baaren. "Unconscious Thought Excels when Challenged: Unconscious Thought Does Not Choke under Pressure." Paper presented at the 11th Society for Personality and Social Psychology Annual Meeting, Las Vegas, NV, January 2010.
  7. Challenging Unconscious Thought

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., and Ap Dijksterhuis. "Challenging Unconscious Thought." Paper presented at the ESCON Transfer of Knowledge Conference, European Social Cognition Network (ESCON), Warsaw, Poland, August 2009.
  8. Unmovable Physique Makes Unshakable Beliefs: The Role of Attention in Processing Abstract Thought

    Keywords: Cognition and Thinking; Values and Beliefs;

    Citation:

    Bos, Maarten W., and Hans IJzerman. "Unmovable Physique Makes Unshakable Beliefs: The Role of Attention in Processing Abstract Thought." Paper presented at the Embodied and Situated Language Processing, Rotterdam, The Netherlands, July 2009.
  9. Complexity and Unconscious thought: Unconscious Thought Outperforms Conscious Thought in Realistic and Simultaneous Decisions

    Keywords: Cognition and Thinking; Decision Making;

    Citation:

    Bos, Maarten W., and Ap Dijksterhuis. "Complexity and Unconscious thought: Unconscious Thought Outperforms Conscious Thought in Realistic and Simultaneous Decisions." Paper presented at the 5th PhD Student Meeting IMM/CAML, Lisbon, Portugal, May 2009.
  10. Complexity and Unconscious Thought: To Go Where Conscious Thought Has Not Gone Before

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., Ap Dijksterhuis, and Rick B. Van Baaren. "Complexity and Unconscious Thought: To Go Where Conscious Thought Has Not Gone Before." Paper presented at the 10th Society for Personality and Social Psychology Annual Meeting, Tampa, FL, February 2009.
  11. Increasing Patient Compliance Through Influence

    Keywords: Power and Influence; Health Care and Treatment;

    Citation:

    Bos, Maarten W., and Joost B.C. Mertens. "Increasing Patient Compliance Through Influence." , The Netherlands, January 01–03, 2009.
  12. The Effect of Low and High Blood Sugar Level on Unconscious Thought (2009)

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., Rick B. Van Baaren, and Ap Dijksterhuis. "The Effect of Low and High Blood Sugar Level on Unconscious Thought (2009)." Paper presented at the 29th Society for Judgment and Decision Making Annual Meeting, Chicago, IL, November 2008.
  13. The Effect of Low and High Blood Sugar Level on Unconscious Thought

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., Rick B. Van Baaren, and Ap Dijksterhuis. "The Effect of Low and High Blood Sugar Level on Unconscious Thought." Paper presented at the ESCON Transfer of Knowledge Conference, European Social Cognition Network (ESCON), Volterra, Italy, September 2008.
  14. The Effect of Low and High Blood Sugar Level on Unconscious Thought (2009)

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., Rick B. Van Baaren, and Ap Dijksterhuis. "The Effect of Low and High Blood Sugar Level on Unconscious Thought (2009)." Paper presented at the 15th European Association of Social Psychology General Meeting, Opatija, Croatia, June 10–14, 2008.
  15. Food for (unconscious) thought?

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., Ap Dijksterhuis, and Rick B. Van Baaren. "Food for (unconscious) thought?" Paper presented at the 9th Society for Personality and Social Psychology Annual Meeting, Albuquerque, NM, February 2008.
  16. The Goal-directedness of Unconscious Thought

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., Ap Dijksterhuis, and Rick B. Van Baaren. "The Goal-directedness of Unconscious Thought." Paper presented at the ESCON Transfer of Knowledge Conference, European Social Cognition Network (ESCON), Brno, Czech Republic, September 2007.
  17. On the Goal-dependency of Unconscious Thought

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., and Ap Dijksterhuis. "On the Goal-dependency of Unconscious Thought." Paper presented at the 8th Society for Personality and Social Psychology Annual Meeting, Memphis, TN, January 2007.
  18. The Goal-directedness of Unconscious Thought

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., and Ap Dijksterhuis. "The Goal-directedness of Unconscious Thought." Paper presented at the Small Group Meeting in Consumer Psychology: Unconscious and Controlled Processes, Enschede, The Netherlands, November 13–14, 2006.
  19. The Goal-directedness of Unconscious Thought

    Keywords: Cognition and Thinking;

    Citation:

    Bos, Maarten W., and Ap Dijksterhuis. "The Goal-directedness of Unconscious Thought." Paper presented at the 2nd Workshop on Cognitive and Social Perspectives on (Un)consciousness, Poland, July 11–14, 2006.