Spanking children makes them dumb

That is the conclusion of a study (paywall) by US researchers: that regular spanking is extremely altering and causes traumatic post-stress disorder reducing the young brain's ability to cope and develop normally.

The good news is that, as the practice of corporal punishment is steadily decreasing worldwide, the intelligence of the new generations is improving overall. In fact, it may be an important factor in the Flynn effect.

Source: Science Daily.
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