**Question:** All of the following are essential features of Attention Deficit Hyperactivity Disease (ADHD) EXCEPT

A. Hyperactivity
B. Impaired attention
C. Impaired working memory
D. Improved memory after sleep

**Core Concept:**
Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder characterized by persistent symptoms of hyperactivity, impulsivity, and inattention. This condition is commonly seen in children, but can also affect adults. The essential features of ADHD include hyperactivity, impaired attention, and impaired working memory.

**Why the Correct Answer is Right:**
The correct answer, "D. Improved memory after sleep," is incorrect because ADHD is primarily associated with impaired cognitive functions, particularly in the areas of attention, working memory, and impulse control. Improved memory after sleep is a normal cognitive process and does not reflect a characteristic feature of ADHD.

**Why Each Wrong Option is Incorrect:**
A. Hyperactivity - This is an essential feature of ADHD, reflecting excessive motor activity and fidgeting in children and adults.
B. Impaired attention - Attention deficits are a hallmark of ADHD, including difficulties with sustained attention, selective attention, and divided attention.
C. Impaired working memory - Working memory impairment is a common feature of ADHD.

**Clinical Pearl:**
ADHD is a complex disorder with multifaceted presentations. While the condition may improve with sleep, the essential features include hyperactivity, impulsivity, and impaired attention, working memory, and executive functions. Understanding these essential features is crucial for making an accurate diagnosis and providing appropriate treatment for patients with ADHD.