People who respond to a horrific trauma with normal upset and anxiety need love, support and space to work through their feelings.

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Anxiety or fear at normal levels aren't necessarily a bad thing.

CNN: Be vigilant, not 'paranoid,' experts say

But with a child with Asperger's, which is a form of autism, " Krouse said, "we have to make sure that we get him back to his normal routines and that if the anxiety levels are overwhelming, to treat those.

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Although in some cases, dark thoughts can be a severe and debilitating symptom of a postpartum anxiety or depressive disorder, usually they are just an unpleasant part of normal adjustment.

CNN: When motherhood becomes a nightmare

Substitute Rafael volleyed United back into contention with a minute of normal time left - but Arsenal survived six extra minutes and an outbreak of mass anxiety at the Emirates to clinch the three points.

BBC: Arsenal 2-1 Man Utd

The second half lacked the you-score, we-score, theatre of the opening 45 minutes but as the match moved into the final 20 minutes of normal time, the players started to tire in the heat and there was an increasing sense of anxiety emanating from the stands.

BBC: Blackpool 3-2 Cardiff

For some people, a bad mood takes the form of depression, anxiety, guilt, shame, panic or anger, he says, and all are perfectly normal.

FORBES: How To Snap Yourself Out Of A Bad Mood

The study results could help distinguish between normal and abnormal processes within the visual cortex and identify what parts of the brain are targets for the treatment of anxiety disorders.

FORBES: How Seeing Changes Your Brain