Tests of Visuospatial and Constructional Skills

Test

Bender-Gestalt Test

Benton Facial Recognition Test Benton Judgment of Line Orientation Test

Block Design Test (WAIS)

Clock-Drawing Test

Hooper Visual Organization Test

Object Assembly Test (WAIS) Visual Form Discrimination Test

Visual perceptual and visual constructional skills; right greater than left

(R > L) parietal lobe Subtle perceptual and visual discrimination; R > L parietal lobe Ability to estimate angular relationships between line segments; rCBF

increases in bilateral temporal-occipital areas; R > L129 Visuospatial organization skills; glucose metabolism increases in posterior parietal lobe; R > L130 Visual neglect, right parietal dysfunction

Visual perceptual fragmentation from bilateral posterior brain dysfunction or right frontal dysfunction Constructional ability, visuospatial perception; posterior brain R > L Visual recognition, posterior brain injury, particularly left parietal lobe

Note: rCBF = regional cerebral blood flow.

within an average range, whereas those patients with right hemisphere damage are more likely to provide impaired scores, particularly if they have posterior lesions.

Poor performance on this test can be caused by impaired visual acuity, psychiatric disorder, significant pain, impairment of visual attention, and fatigue.12 This test may not detect brain damage located in the left hemisphere, and it requires the administration of other neuropsychological tests to improve the overall neuropsychological screening.

Block Design Test

This test consists of assembling 1-in. blocks with red and white colors to reproduce a specific printed design from a stimulus card. The task may require the use of four to nine blocks. It is one of the performance subtests of the Wechsler Adult Intelligence Scales. It is a timed test, and each design becomes more difficult than the prior design.133 This test is generally recognized as the best measure of visuospatial organization within the Wechsler Scales.3 It reflects a general ability in most individuals so that cognitively capable persons who are academically or culturally limited will frequently obtain their highest score among the 11 subtests. However, Block Design scores tend to be lower in the presence of any kind of brain dysfunction. It is particularly sensitive in detection when the injury is located in the frontal or parietal lobes. In normal subjects, Block Design performance is associated with an increased glucose metabolism in the posterior parietal regions when measured by PET scan. Generally, the more intense metabolic activation is in the right cerebral hemisphere.130

Edith Kaplan argues that the examiner should note whether lateralized errors on this test tend to occur more at the top or the bottom of the constructions, as the upper visual fields have a temporal lobe component, whereas the lower visual fields have parietal components. Thus, a pattern of errors clustering at the top or a bottom corner can give some indication of the anatomical site and extent of the lesion.3 By taking a qualitative rather than a quantitative approach to Block Design analysis, other information may be detected. For instance, patients with left hemisphere, particularly parietal, lesions tend to show confusion and simplification while handling the design in a concrete fashion. However, their approach to the designs is likely to be orderly; they typically work from left to right, as do intact subjects, and their construction usually preserves the square shape of the design. However, their greatest difficulty may be in placing the last block, which most often will be on their right. On the other hand, patients with right-sided lesions may begin at the right of the design and work to their left. The visuospatial defect reveals itself in disorientation, design distortions, and misperceptions. Left visuospatial inattention may compound this design-copying problem, resulting in two- or three-block solutions to the four-block designs.3

Hooper Visual Organization Test

The Hooper Visual Organization Test consists of showing the patient 30 pictures of objects that have been cut up and placed in different positions.134 The patient must visually examine each picture and then decide what it would represent if it were assembled. The patient must write down the name of the object, such as a fish, ball, or key. Most individuals can complete this test in approximately 15 min.12

Cognitively intact persons generally fail no more than six items on this test. More than 11 failures usually indicates organic brain pathology. The test appears sensitive to bilateral posterior brain dysfunction or, in some instances, dysfunction of the right frontal lobe. These patients tend to examine only one object singly rather than visually organize the different objects into a cohesive visual organization. Poor performance on this test also can be caused by low intellectual ability, psychiatric disease, or poor effort.

Object Assembly Test

The Object Assembly Test is another subtest of the WAIS.133 It requires the patient to assemble cardboard figures of familiar objects. There are timed portions to this test, and the patient must form the puzzle parts into a man, a face profile, an elephant, a house, and a butterfly. The patient is not told the name or nature of the object and must identify the object during the assembly process.

The speed component of this test renders it relatively vulnerable to brain damage generally.3 It tests constructional ability and visuospatial perception and is sensitive to posterior brain lesions, more so on the right side than the left. In terms of internal correlations on the WAIS, the Object Assembly and Block Design tests correlate more highly with one another than do any of the other Wechsler subscale tests.

Patients who have posterior right hemisphere damage typically will perform poorly on this test, and patients with frontal lobe injuries may show poor organization and planning skills in their approach to the test. If the brain injury is significant, the patient may not comprehend the test instructions and possibly could require extra examples, such as described in the test manual.

Visual Form Discrimination Test

This test consists of a series of three geometric figures that the patient must match to one of four sets of designs.135 It is a multiple-choice test of visual recognition. Of the four sets of designs, one of the designs is an exact replica of the stimulus figure, while the others may vary to a subtle degree. This is a visual recognition test, and it is sensitive to posterior brain injury, particularly in the left parietal lobe. One of its strengths is that it can be administered to patients who are unable to speak English, as the patient only must point to one of four sets of figures on a sheet of cardboard. Visual memory plays little role in this test. A number of factors may interfere with test performance. These include impaired visual acuity, psychiatric disturbances, visual field defects, and poor motivation. Poor performance on this test alone may be sufficient to provide gross evidence of brain injury.12

Measuring Sensorimotor Function

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