When are you actually an adult? - Shannon Odell — Transcript

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1. 0:06Most countries recognize 18 as the start of adulthood
2. 0:10by granting various freedoms and privileges.
3. 0:13But is age the best way to measure maturity?
4. 0:17I was born 12:05 AM on November 6th—
5. 0:205 minutes short of being eligible to vote in the election tomorrow.
6. 0:24Meanwhile, your big brother— yours truly—
7. 0:27was born 15 minutes earlier, so I can vote.
8. 0:30It’s arbitrary and unfair!
9. 0:33The voting age should be lowered to 16!
10. 0:37I firmly disagree!
11. 0:38No way 16-year-olds are mature enough to make decisions with national consequences.
12. 0:42I’m eligible and I don’t even know who’s running.
13. 0:46Meanwhile, I know the candidates inside and out.
14. 0:50She's obsessed with politics.
15. 0:52Exactly! If 16-year-olds aren’t mature enough to vote,
16. 0:55then by that same logic, they shouldn’t be allowed to drive.
17. 0:58I firmly disagree! I’m an excellent driver!
18. 1:01And I’ve never gotten a ticket, unlike some people.
19. 1:04That’s so unfair! That stop sign was hidden by a tree.
20. 1:08I think you both make valid points.
21. 1:10And questioning the age limits of adulthood is well warranted.
22. 1:14Some countries have lowered the voting age to 16,
23. 1:17and cultural coming-of-age ceremonies are often celebrated at different ages.
24. 1:21As there seems to be no consensus on exactly when we reach maturity,
25. 1:26perhaps science can give us a clearer answer.
26. 1:30One way neuroscientists have looked to define adulthood
27. 1:33is by when the brain is fully grown.
28. 1:36Brain development involves two trajectories.
29. 1:39First, there's a reduction in gray matter.
30. 1:42Gray matter consists of cells and connections
31. 1:44that facilitate communication at short ranges,
32. 1:47creating dense, information-processing hubs.
33. 1:51While a reduction may seem like a bad thing,
34. 1:53what’s happening is a selective pruning.
35. 1:56Connections that are used are kept and strengthened,
36. 1:59while under-used ones are weeded away,
37. 2:02creating a brain that is both fine-tuned to its environment and energy efficient.
38. 2:08This gray matter reduction coincides with an increase in white matter.
39. 2:13White matter refers to connections that are myelinated,
40. 2:16coated in a layer of insulation,
41. 2:18allowing for fast far-range communication between information hubs.
42. 2:23For example, these paths connect regions that signal
43. 2:25the pleasure of immediate reward with regions that help us plan ahead,
44. 2:30allowing us to make more balanced, forward-thinking decisions.
45. 2:34Imaging studies show that white and gray matter volumes
46. 2:37undergo drastic changes during adolescence,
47. 2:39and continuing through your twenties.
48. 2:42But the brain’s journey is far from finished,
49. 2:44as various experiences continue to reshape its connections
50. 2:48throughout your lifetime.
51. 2:49So brain structure alone may not give us our answer.
52. 2:53Another way scientists have tried to define adulthood
53. 2:56is by measuring cognitive development—
54. 2:59when are you able to learn and complete mental tasks
55. 3:02at the same efficiency as older adults?
56. 3:05By this definition, adulthood may begin as early as 16,
57. 3:08as teens perform just as well on tests
58. 3:10that assess reasoning, problem-solving and critical thinking.
59. 3:14Though capable of making smart, well-informed decisions,
60. 3:17teens may be more susceptible to external pressures.
61. 3:21Studies show that when performing risk- taking and self-control related tasks,
62. 3:2618 to 21 year olds behave much like older adults.
63. 3:29But when these tests include an emotional element—
64. 3:32such as utilizing self-control when identifying fearful faces—
65. 3:36or a social element—
66. 3:37such as making a decision in the presence of a friend—
67. 3:40different patterns emerge.
68. 3:42Under these influences, 18 to 21 year olds tend to behave more like younger teens,
69. 3:47and their brains show younger-teen-like patterns of activity.
70. 3:51In other words, during your teens and early twenties,
71. 3:54your brain is wired to place more value and attention
72. 3:57on social and emotional elements.
73. 4:00This allows emerging adults to better explore their identities
74. 4:03and connect with others,
75. 4:04but may also create more vulnerability to negative peer influence
76. 4:08and rash heat of the moment decisions.
77. 4:12For this reason, many scientists argue that judicial systems
78. 4:15should expand juvenile courts to include
79. 4:17those in their late teens and early twenties,
80. 4:20as current systems fail to recognize
81. 4:22how the emerging adult brain is still changing.
82. 4:25So when are you actually an adult?
83. 4:27As you can see, there is no exact age or moment
84. 4:30in development that we can point to.
85. 4:32Instead, neuroscience suggests that there are waves of maturity.
86. 4:36As different brain regions and mental abilities mature at different times,
87. 4:40so do different adult-like states and behaviors.
88. 4:44Not everyone will reach each wave of maturity at the same age.
89. 4:47Each person’s journey to adulthood is unique,
90. 4:50influenced by genetics, environment, and experience.