Keep probes brief, straightforward
Cognitive exams of patients with suspected psychiatric disorders should be simple, easy to administer and focused on a single domain of cognition. “Probes should be brief. They should not require specialized equipment. The Purdue Pegboard Test might be a great neuropsychological instrument, but very few of us carry a pegboard around in our medical bags,” Dr. Ovsiew said.
The probe administered should also be accessible to the patient. The serial sevens clinical test, where a patient is asked to repeatedly subtract 7 from 100, is only effective at testing concentration if the patient is capable of completing the test. “There are going to be patients who can’t do the task, but it’s not because of concentration failure, it’s because of subtraction failure,” he said.
When assessing attention, effective tasks include having the patient perform the digit span test forward and backward, count backward from 20 to 1, listing the months of the year in reverse, and performing the Mental Alternation Test. However, Dr. Ovsiew explained there may be some barriers for patients in completing these tasks. “The person may be aphasic and not know the alphabet. The person may have English as a second language and not be skilled at giving the alphabet in English. In some cases, you may want to check and not assume that the patient can count and does know the alphabet.”
In assessing language, listen for aphasic abnormalities. “The patient, of course, is speaking throughout the interview, but you need to take a moment to listen for prosody, to listen to rate of speech, to listen for paraphasic errors or word-finding problems,” Dr. Ovsiew said. Any abnormalities should be probed further through confrontation naming tasks, which can be done in person and with some success through video, but not by phone. Naming to definition (“What do you call the part of a shirt that covers the arm?”) is one way of administering the test over the phone.
Visuospatial function can be assessed by clock drawing but also carries problems. Patients who do not plan their clock before beginning to draw, for example, may have an executive function problem instead of a visuospatial problem, Dr. Ovsiew noted. Patients in whom a clinician suspects hemineglect should be given a visual search task or line by section task. “I like doing clock drawing. It’s a nice screening test. It’s becoming, I think, less useful as people count on digital clocks and have trouble even imagining what an analog clock looks like.”
An approach that is better suited to in-person assessment, but also works by video, is the Poppelreuter figure visual perceptual function test, which is a prompt for the patient that involves common household items overlaying one another “in atypical positions and atypical configurations” where the patient is instructed to describe the items they see on the card. Another approach that works over video is the interlocking finger test, where the patient is asked to copy the hand positions made by the clinician.
Dr. Ovsiew admitted that visuospatial function is nearly impossible to assess over the phone. Asking topographical questions (“If you’re driving from Chicago to Los Angeles, is the Pacific Ocean in front of you, behind you, to your left, or to your right?”) may help judge visuospatial function, but this relies on the patient having the topographic knowledge to answer the questions. Some patients who are topographically disoriented can’t do them at all,” Dr. Ovsiew said.
Bedside neuropsychiatry assesses encoding of a memory, its retention and its retrieval as well as verbal and visual cues. Each one of these aspects of memory can be impaired on its own and should be explored separately, Dr. Ovsiew explained. “Neuropsychiatric clinicians have a rough-and-ready, seat-of-the-pants way of approaching this that wouldn’t pass muster if you’re a psychologist, but is the best we can do at the bedside.”
To test retrieval and retention, the Three Words–Three Shapes test works well in person, with some difficulty by video, and is not possible to administer over the phone. In lieu of that test, giving the patient a simple word list and asking them to repeat the list in order. Using the word list, “these different stages of memory function can be parsed out pretty well at the bedside or chairside, and even by the phone. Figuring out where the memory failure is diagnostically important,” Dr. Ovsiew said.
Executive function, which involves activation, planning, sequencing, maintaining, self-monitoring, and flexible employment of action and attention, is “complicated to evaluate because there are multiple aspects of executive function, multiple deficits that can be seen with executive dysfunction, and they don’t all correlate with each other.”
Within executive function evaluation, the Mental Alternation Test can assess working memory, motor sequencing can be assessed through the ring/fist, fist/edge/palm, alternating fist, and rampart tests. The Go/No-Go test can be used to assess response inhibition. For effortful retrieval evaluation, spontaneous word-list generation – such as thinking of all the items one can buy at a supermarket– can test category fluency, while a task to name all the words starting with a certain letter can assess letter stimulus.
Executive function “is of crucial importance in the neuropsychiatric evaluation because it’s strongly correlated with how well the person functions outside the office,” Dr. Ovsiew said.
Global Academy and this news organization are owned by the same parent company. Dr. Ovsiew reported relationships with Wolters Kluwer Health in the form of consulting, receiving royalty payments, and related activities.