The primary survival function of the Toddler brain—the limbic area that’s developed by age 3—is to generate an alarm. Toddlers can’t take care of themselves, solve problems, or keep themselves safe. Their negative emotions are alarms to summon adults who will do those things for them.
All alarm systems, negative feelings included, are calibrated to give false positives. You don’t want a smoke alarm that doesn’t go off until the house is in flames; you want it to go off when there’s just a little smoke, even if that means it occasionally gets triggered when someone is cooking or having a cigarette. The Toddler brain functions as if the smoke alarm is the fire, instead of a signal that a fire might possibly exist. That’s like hearing a smoke alarm and screaming, “We’re all going to die!” We actually come close to that level of error by assuming that Toddler brain emotional alarms represent certain reality.
The Adult brain—not fully developed until the third decade of life—reacts to smoke alarms by checking out the signal to see if there really is a fire or just something cooking. If there is a fire, the focus is on putting it out, rather than reacting in panic, trying to ignore it, or blaming it on someone. In the Adult brain we pay attention to feelings as important signals but don’t validate them as reality. Negative feelings are regulated with reality checks (is there really a fire) and plans for improvement (put out the fire).
In addition to reality-testing, the primary features of the Adult brain are appraisal, calculations, judgment, self-regulation (of emotions and impulses), and what psychologists call theory of mind, which is the ability to reflect on mental states of self and others. With these tools it interprets and explains experience: This is why I feel this way and comes up with an action-plan - this is what I will do to improve how I feel.
Most important in regard to love relationships, the Adult brain creates value. Creating value is holding persons (objects and ideas) as important and worthy of appreciation, time, energy, effort, and sacrifice. In the process of creating value, the Adult brain constructs the meaning of our lives.
The Toddler brain is impulsive, simplistic, self-obsessed, and given to power struggles: “Mine!” and “No!” Most relevant when it comes to maintaining love relationships, the Toddler brain is subject to splitting, that is, all-or-nothing, black-and-white thinking. You’re all good when I feel good, and bad when I don’t; you’re interesting when I feel vibrant and dull when I feel bored. In the Adult brain, we can regulate negative feelings and impulses, integrate, enjoyment and disappointment, see other perspectives, and analyze our own experience. There we can plan, weigh evidence, make sound judgments, and build a life of value and meaning.
The downside of late maturity in the Adult brain is that it comes online long after the Toddler brain has already formed habits of coping with the alarms it raises, mostly through blame, denial, and avoidance. Under stress, these fortified neural patterns, reinforced countless times over the years, hijack higher cognitive processes. Instead of modifying Toddler brain alarms with assessments of reality, the hijacked prefrontal cortex validates its alarms and justifies its impulsivity and overreactions.
“If I’m angry, you must be doing something wrong.”
“If I'm anxious, you must be threatening, rejecting, or manipulative.”
“If I’m uncomfortable, you must be failing me.”
If the couple remains in the Toddler brain, the blamed partner will inevitably blame back, creating resentment, hostility, and greater distance between them.
Why Toddler Brain Love Must Turn Negative
Did you ever wonder why people are more likely to notice things that stir negative emotion than those that might invoke a positive response? On autopilot, we give disproportional weight to the negative. Because they’re more important for immediate survival, negative emotions get priority processing in the brain. They give us the instant adrenaline jolt we need to avoid snakes in the grass and fend off saber tooth tigers, at the cost of noticing the beauty of our surroundings.
Ironically, positive emotions are more important to long-term well-being. You’ll live longer and be healthier and happier if you experience considerably more positive emotions than negative ones. Life is better for those who are able to appreciate the beauty of the rolling meadow and the sun dappling the edges of surrounding trees, as long as they are able to notice the snake in the grass, too. We have to survive the moment to appreciate the world around us.
The negative bias of emotions is why loss causes pain disproportionately to the joy of equivalent gain. Having a nice meal is enjoyable but, in most cases, incomparable to the distress of missing a meal altogether. Finding $10,000 will be pleasant for a day or so; losing $10,000 can ruin many, many days. More poignantly, having a child is a joyous occasion; losing a child takes a lifetime of recovery.
In my Toddler brain, the negative bias of emotions makes it unlikely that I’ll notice all the things my partner does that benefit me (appreciation is the province of the Adult brain), but I'll surely resent when she doesn’t do what I want. In family relationships, research shows that it typically requires at least five positive gestures to counterbalance one little negative remark. If research just measured Toddler brain exchanges, the ratio of positive to negative no doubt would be higher just to maintain neutrality.