Rewire Your Brain: Think Your Way to a Better Life

amygdalon
, because of its shape. The amygdala is triggered 
by intense emotional states like fear, and it assigns emotional inten-
sity to the incoming information. The amygdala can be triggered by a 
quick glance from a very attractive person or by your boss glaring at 
you. It often serves as a sort of panic button. 
The other memory structure is called the
hippocampus
, the Greek 
word for “ seahorse, ” because of its shape. Researchers have recently 
discovered the birth of new neurons, or
neurogenesis
, in the hippo-
campus. Scientists had previously believed that neurogenesis was 
not possible. The discovery of new neurons in a part of the brain 
that lays down new memories highlights the importance of cultivat-
ing your memory skills to rewire your brain. 
The hippocampus and the amygdala are involved in two differ-
ent types of memory: explicit and implicit, respectively. Explicit 
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F i r i n g t h e R i g h t C e l l s To g e t h e r
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memory is used when you try to remember what you had for dinner 
last night, when your next dental appointment is, or the name of 
a familiar - looking woman who ’ s standing next to the water cooler. 
These are facts, dates, words: pieces of information. It is this type 
of memory that people often complain they are losing. 
Implicit memory is often thought of as unconscious memory. It 
reacts to the emotional intensity of events and situations; when the 
situation is potentially dangerous, it activates the fear system in your 
body. This is often called the fi ght - or - fl ight response. 
This alarm system is automatic; that is, it happens before you 
have time to think about it. Thousands of years ago, when our 
ancestors encountered a predatory animal like a lion, it was best 
to react immediately and not stand around thinking about the lion, 
admiring its beauty or wondering why it was bothering them instead 
of tracking down some tasty antelope. Thus, the fast track to the 
amygdala kept our ancestors alive. 
A balance between your sympathetic nervous system (which acti-
vates you) and your parasympathetic nervous system (which calms 
you down) allows you fl exibility. I ’ ll describe this in detail in chap-
ter 9 . These systems, along with the circadian rhythm, nutrition, 
exercise, relaxation, and meditation, can help you to be calm and 
positive. 
Let ’ s change the Hurricane Katrina story and say that you didn ’ t 
go to Houston. You might have been so fi lled with anxiety that you 
drove like mad straight north to escape the driving rain. At one point 
you pulled over because you couldn ’ t see the road in front of you. 
A tree limb fell on your car, and you were fi lled with even more 
anxiety. Months later, during a rainstorm, you feel a surge of anxiety. 
You don ’ t know why you feel this way, but your amygdala remem-
bers quite well, because it triggers your hippocampus and cortex to 
remind you of the day you escaped Katrina. 
The amygdala helped you by stirring enough fear in you to make 
you pull off the road, but it also made you oversensitive to rain-
storms. The problem is that this fear system is activated even when 
you don ’ t need to be fearful. In other words, sometimes it is turned 
on when it would be better to have it turned off. Chapter 2 describes 
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16 Rew i r e
Yo u r
B r a i n
how you can tame your amygdala so that it doesn ’ t become overacti-
vated when you need to stay calm. 
Your frontal lobes are sometimes called the executive brain or the 
executive control center because they are important in orchestrating 
the resources of the rest of your brain. The frontal lobes decide 
what to do, how to stay positive, and how to appreciate the larger 
picture of life. By being positive and active, you ’ ll rewire your frontal 
lobes. 
The OFC and some other parts of the brain constitute what has 
been called the social brain because this system of neurons thrives 
on social interaction. When these neurons are activated effectively, 
you experience fewer psychological problems and better mental 
health. Chapter 7 is devoted to the many benefi ts of your social brain 
networks. 
The bonding experiences you have had with your parents 
since the beginning of your life have affected your social brain. Your 
later relationships then modify those neural connections. Positive 
relationships enhance your sense of well - being, whereas negative 
relationships leave you with the opposite feeling. 
We know that neurochemicals such as oxytocin are involved in 
childbirth and bonding, and that later in life they become activated 
in intimate relationships. Higher oxytocin levels help to blunt pain 
and make us feel comforted by other people. For this reason, oxyto-
cin is referred as the “ cuddling hormone. ”
The recent discovery of