It’s December 2000. Close to 25% of Black South Africans are living with HIV/AIDS and the antiretroviral therapies retail at over $1,000 – a third of the average annual salary – putting them out of reach for many.

Two years earlier, Nelson Mandela’s African National Congress had signed into a law an agreement that allowed the government to purchase brand-name drugs at cheaper rates than those offered by the big pharmaceutical companies. In response, 39 drug makers had sued South Africa and Mandela, claiming this violated price protections and intellectual property rights.

GlaxoSmithKline (GSK) were included in this group of claimants. But they had a new chairman of research and development: Dr Tadataka “Tachi” Yamada.

Yamada was horrified to learn that the company was a claimant in the class action and, through discussions with his research staff, found he was not alone in his opposition to the lawsuit. His team wanted to be a part of the solution to global health issues, not party to a lawsuit preventing such drugs from reaching those in dire need. However, none of the team felt they had the power to change the company’s direction.

This feeling of being outnumbered, of your voice being silenced and that you can’t affect change are surprisingly common. In organisations, people are embedded in social and cultural systems. Those systems can actively work against an individual to maintain the status quo.

This article discusses social dynamics within teams and the psychology of affecting cultural change as an individual.

Yamada’s Approach

At GSK, Dr Yamada and his research team were an island, but he knew that they could build bridges across the organisation to help them get where he felt they needed to go.

In one-on-one meetings with individual Board members, Yamada argued that the long-term success of the business relied on access to treatment; not on high prices to the consumer. He stressed the company’s moral responsibility to alleviate human suffering, stated that GSK can’t make medicines that save lives and then not allow people access to them, and reminded the Board of GSK’s public mission: to help people “do more, feel better, and live longer.”

Public protests mounted against GSK and other drug companies. This, Yamada argued, would mean that maintaining the current approach would become a PR nightmare.

Yamada didn’t just highlight why the existing approach was incongruent with the mission and damaging to the long-term sustainability of the business; he also provided a roadmap. Together with his team, Yamada co-created a vision for how GSK could also become a leader in the fight against TB and malaria, diseases that also were disproportionately impacting third-world populations.

The Board acknowledged both Yamada’s concerns and the recommendations from the team. Within 6-months, GSK (and others) reduced the prices of antiretroviral drugs by 90% or more, and all 39 companies dropped the lawsuit.

Under Yamada’s direction, one of GSK’s major laboratories in Tres Cantos, Spain, was converted into a profit-exempt laboratory that focused only on diseases in the developing world.

Using his influence, Dr. Yamada also spurred GSK into allocating resources for affordable access to medications and development of future therapies. Today, GSK’s mission is “to unite science, technology and talent to get ahead of disease together” and “to positively impact the health of 2.5 billion people by the end of the decade.”

Top executives at GSK became leaders in global health issues. Andrew Witty became CEO in 2008 and became one of the leading spokespersons for global health in the pharmaceutical industry. GSK executive Chris Viehbacher became the CEO of Sanofi, and a champion of global health. Both are partners of the Gates Foundation on global health initiatives.

The culture of GSK had evolved quickly: From an organisation that considered suing Nelson Mandela an acceptable option towards an organisation that aims to get ahead of disease and sets aside not-for-profit resources for research.

Dr Yamada’s story challenges a common belief: that individuals, especially in large systems, are powerless to enact cultural change. But culture isn’t static – it’s an emergent property of people and their shared behaviours. What Yamada tapped into wasn’t just personal conviction; it was a deep understanding of human psychology, influence, and group dynamics. What made it possible for Dr Yamada to catalyse such a change in the culture?

A Culture From One

While cultural change often feels like the domain of collectives or movements, the story of Dr Yamada shows that individuals can catalyse transformation, if they know how to act with psychological insight.

Four key psychological dynamics underpinned Yamada’s impact:

Clarity of Conscience and Direction

Yamada had a strong internal compass and a clearly defined belief: that denying access to life-saving drugs was morally indefensible. Yamada’s objection to the lawsuit wasn’t just strategic; it was rooted in his identity and ethical beliefs. Research suggests that people who act in alignment with their core values experience more confidence and reduced cognitive dissonance.

Cognitive dissonance refers to the mental discomfort experienced when an individual’s behaviours are inconsistent with their beliefs, values, or morals. This inconsistency leads to unpleasant feelings, which people attempt to alleviate by rejecting, explaining away, or avoiding new information (Hinojosa et al., 2017).

However, when we perform actions in line with our core values, our brain recognises this alignment as a positive and meaningful experience, indirectly stimulating dopamine release. A study published in the Journal of Personality and Social Psychology examines how self-connection, defined as awareness, acceptance, and alignment with one’s true self, contributes to psychological well-being (Klussman et al., 2022).

This offers a profound insight: we are neurologically wired to seek satisfaction and pleasure by staying true to our values and are in discomfort when we do not stay true to those values.

Sustained Focus on Direction

Culture change is often about keeping the long game in mind. Yamada maintained progress through conversations, planning, and vision-building. This sustained focus allows for consistency, which builds trust – a critical element for gaining followers in change movements.

Psychologically, sustained effort toward change often comes from intrinsic motivation: doing something because it matters deeply, not just because it’s externally rewarded. This is known as goal persistence and describes goals that are of high personal relevance or meaning to the individual and the individual’s continued or repeated action in line with that goal (Brandstätter & Bernecker, 2022).  

But being persistent in the pursuit of an internally motivated goal doesn’t drive culture change on its own. Yamada required others to join his goal. He made the case to others not just with logic, but with narrative.

Our brains are wired to think in narrative and to respond to narrative, to move others and to be moved by stories. It is simple and elegant and profoundly human. Yamada recognised that, if we want to lead people, the most natural and compelling way to do it is to invite them in with a story.

This narrative thinking is powerful in the neuroscience of storytelling. When we discuss facts, dopamine is released to help us remember and the Broca’s and Wernicke’s areas of the brain are activated.

But when we describe stories, oxytocin and cortisol are released, building connection and increasing attention. Multiple areas of the brain – including the motor cortex, sensory cortex and frontal cortex – are activated, and research has found neural coupling occurs: the neurons in our brain fire in the same patterns as the storyteller’s (Stephens, 2010).

Yamada’s consistency, focus and ability to weave a narrative of the future (“This is where GSK should be”) are influential tenets in creating connections within groups and creating connection to a shared purpose.

Using Privilege to Support Others Without

Yamada had positional power. Unlike junior researchers, he had access to decision-makers and couldn’t be easily silenced. Rather than wielding power for self-interest, he used it to amplify the concerns of those with less power. This allyship helps to create psychological safety: the space where people feel they can speak honestly without fear of reprisal.

Many people believe that culture change happens from the top-down. Often, change initiatives will focus on the C-suite and senior leaders, and often ignore the day-to-day experience of the frontline employees.

Leaders are important and influential in cultural change. But culture lies in the day-to-day, in the mundane and routine. Culture often changes not from the top dictating, but when the top supports the ground-level moral voice.

Yamada used his position to create the environment for influence, to gain followship and support for the transformation. But, even with this allyship and support, he still needed to influence others.

Understanding How to Influence Others

Yamada didn’t storm in with accusations; he made individual appeals to each Board member, framing his argument in ways that would matter to them– reputation, mission alignment, long-term business viability. He anticipated resistance and reframed the issue as both a moral and a strategic imperative.

Influence in organisations is rarely about raw power. It’s about knowing how to frame the future in a way others can buy into.

Yamada’s approach to influence was not accidental; it reflects principles well-established in the psychology of persuasion. Social psychologist Robert Cialdini outlines seven key principles of influence: reciprocity, commitment and consistency, social proof, authority, liking, scarcity, and unity (Cialdini, 2021).

Yamada invoked several of these:

• Authority: by speaking from a senior leadership position;
• Consistency: by aligning the company’s actions with its publicly stated mission; and
• Social proof: by reflecting the growing consensus within his team and the public

Most importantly, he activated unity – a sense of shared identity and purpose within GSK. Cultural change requires more than pressure; it requires connection. By making others feel part of a larger, morally compelling narrative, Yamada moved them not just logically, but emotionally and socially.

Creating a Cultural Movement

Together, Yamada utilised these four dynamics to encourage collective efficacy.

This is a core concept in social cognitive theory, which describes a group’s shared belief in its ability to achieve goals through coordinated effort (Bandura, 1997). It’s not simply the sum of individual perceptions of a group’s efficacy but a group-level artifact, influencing what a group chooses to do, how much effort they put in, and their resilience in the face of setbacks.

Yamada’s actions – driven by conscience, sustained focus, narrative intelligence, and strategic influence – seeded that belief within his team, and then within the wider organisation. By stepping forward with clarity and courage, he gave others permission to voice their concerns. By using his power to protect and elevate others, he created psychological safety. And by articulating a shared vision of a better path forward, he turned isolated values into a collective mission.

This is how culture changes: not all at once, but through a cascade. One person acts. That act creates possibility. That possibility becomes shared belief. And that belief becomes momentum. When that act is rooted in purpose, clarity and direction, is sustained and used to build relationships, that momentum is enhanced further.

Culture isn’t changed by authority alone. It changes when people see that change is possible together.

The Mosquito Effect

From pandemics to climate change to systemic inequality, the world continues to face problems that require coordinated, courageous leadership. But in complex systems, many people feel paralysed – like they’re too small to make a difference.

Stories like Yamada’s remind us that even in rigid systems, change is possible. And often starts with one person speaking up. Systems don’t change through noise alone, but through clarity, consistency, and the courage to act. In short, through leadership.

Leadership isn’t just a title – it’s a practice. One person, using their insight, values, and position with care, can shift a system. Not by force. But by creating the conditions where others can step forward too.

There’s an old African proverb that says: “If you think you’re too small to make a difference, try sleeping with a mosquito.”

Culture often feels like a vast, immovable force. But it’s made up of people. When individuals act with clarity, courage, and psychological insight, they can shift the system. Not alone. But not helpless either.

Yamada didn’t change GSK by himself. But he sparked something, and others followed. That’s the essence of leadership, and the power of collective efficacy: not commanding change, but enabling others to see that change is possible, and that they are part of it.

Dr Yamada didn’t change culture by shouting the loudest. He changed it by being consistent in his values, strategic in his influence, generous with his power, and relentless in his vision.

That’s not charisma; it’s psychology. And it’s something more of us can learn to do.

References

Bandura, A. (1997). Self efficacy: The exercise of control. New York: W. H. Freeman and Company.

Brandstätter, V., & Bernecker, K. (2022). Persistence and disengagement in personal goal pursuit. Annual review of psychology, 73(1), 271-299.

Cialdini, R. B. (2021). Influence: The psychology of persuasion (rev. ed.). Harper Business.

Goldie, P. (2009). Narrative thinking, emotion, and planning. The Journal of Aesthetics and Art Criticism, 67(1), 97-106. https://doi.org/10.1111/j.1540-6245.2008.01338.x

Hinojosa, A. S., Gardner, W. L., Walker, H. J., Cogliser, C. C., & Gullifor, D. P. (2017). A review of cognitive dissonance theory in management research: Opportunities for further development. Journal of Management, 43(1), 170–199. https://doi.org/10.1177/0149206316668236

Klussman, K., Curtin, N., Langer, J., & Nichols, A. L. (2022). Self-connection: A mechanism underlying the relationship between trait mindfulness and authenticity. Journal of Personality and Social Psychology, 122(3), 459–478. https://doi.org/10.1037/pspp0000394

Stephens, G. J., Silbert, L. J., & Hasson, U. (2010). Speaker-listener neural coupling underlies successful communication. Proceedings of the National Academy of Sciences of the United States of America, 107(32), 14425–14430. https://doi.org/10.1073/pnas.1008662107