Balancing Loop

Balancing feedback loops, or negative feedback loops, are circles of cause and effect that counter a change with a push in the opposite direction. The harder the push, the harder the system pushes back. Balancing feedback loops bring stability or stubbornness to a system (depending on how it is perceived), so they are essential and pervasive.

When the internal temperature of your body increases, you sweat, and as that sweat evaporates from the warm surface of your body, you cool down: balancing the initial increase. When you are cool, you sweat less, so there is less sweat to evaporate and it drains less heat allowing your body temperature to rise. At the same time, if your body temperature drops you may start shivering, releasing more heat to warm your body, balancing the initial decrease. In biology, the concept of homeostasis is all about balancing feedback. Cells and living organisms and humans have evolved myriad mechanisms for keeping themselves and their immediate environments stable.

In predator-prey ecosystems, when the number of predators increases, they consume more of their prey, and as the prey become more scarce, more predators die due to the lack of food resources. The number of predators will hopefully approach a sustainable level that ecologists call the carrying capacity.

In our political system, when a party gains more power, they are attributed more responsibility for the problems that exist and will be less likely to win over voters in the next election. This is why the number of representatives from each party seems to fluctuate around a pretty even split over the years and one party never stays in power for too long

Often in a balancing feedback loop, there is some sort of implicit or explicit goal. When the distance between your car and the car in front of you increases you accelerate, closing the gap. When the distance between you and the car becomes less than your desired distance (you’re to close) you will decelerate, either letting the friction of the road slow you down or applying the breaks. Next time you drive think about when you accelerate and decelerate  and why.  How frequently do you switch from accelerating to decelerating? If you increase your desired distance between yourself and the car in front of you, will you switch more rapidly or less rapidly?

Additional Examples:

  • Anything that is trying to regulate itself to maintain a certain level of desired amount
  • When a company gets too big and becomes a monopoly, government restrictions force it to break up
  • As more immigrants enter the U.S. borders, local residents become worried that these immigrants are stealing jobs and sucking away resources – this leads the U.S. to pass stricter laws aimed toward slowing down immigration.
  • When a company has too much inventory supply that it needs to get rid of, it cuts prices to attract more customers to buy their product. This in turn leads to the supply depleting.
  • In a basketball game, when one team is leading by too much, the players become complacent and careless, causing the huge lead to diminish
  • When we are hungry, we eat more food, which makes us less hungry

++

Additional Reading:

Advertisements

7 comments

  1. Pingback: Systems & Us

Leave a Thought

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s