• striking loss of concern and lack of anxiety
• loss of initiative
• flat affect (does not display any emotion)
• indecision
• inappropriate mood
• lack of spontaneity
• decreased interest in daily living activities
• impaired judgment

• excessive manual exploration of the environment
• withdrawal from social interaction
• inability to function or interact in social or personal situations
• inability to maintain employment
• decreased ability to function in self care
• behavior that is inappropriate relative to the environment

• echolalia (repetition of anything spoken to the person)
• speech is incomprehensible jargon
• aphasia (decreased language ability, difficulty speaking or understanding speech)
• inability to comprehend speech
• difficulty finding a word
• shrinking vocabulary
• inability to speak
• inability to repeat a phrase
• poor enunciation
• decreased ability to read or write
• inability to name objects

• loss of cognitive/intellectual skills
• specific disorders of problem solving/learning:
  • inability to generalize
  • loss of abstract thinking
  • impaired calculating ability
  • inability to learn
• weakness
• increased muscle tone
• urinary incontinence
• progressive dementia
• memory loss

The health care provider bases the initial diagnosis on history and symptoms, signs, and tests, and by ruling out other causes of dementia including dementia due to metabolic causes. Neurologic examination may reveal signs that vary according to the which part of the brain is afffected. Temporal and frontal lobe signs are most common, with resulting behavioral and language changes.

There may be other abnormalities, including frontal release signs (presence of abnormal reflexes) and exacerbation of muscle stretch reflexes. Psychologic studies and tests of sensation, cognitive function, and motor function may be abnormal.

• Neuropsychologic assessment shows a pattern of mental decline that suggests selective loss of cognitive function that can be localized to the frontal and/or temporal lobes of the brain.
• An EEG (electroencephalogram) shows nonspecific changes in electrical activity of the brain.
• A head CT scan shows loss of tissue mass of affected lobes of the brain.
• A brain MRI can detect mild degrees of frontal and temporal atrophy missed by the head CT scan
• Cerebrospinal fluid examination after a lumbar puncture is usually normal.

It is important to note that the definitive diagnosis can only be made by brain biopsy since the demonstration of Pick bodies must be done with a microscope by an experienced neuropathologist. However, ongoing efforts are directed at developing a biological marker that would allow a firm diagnosis without the need for such an invasive procedure.