diff --git a/tests/test_viz.py b/tests/test_viz.py
index 5f945651..154cb6b0 100644
--- a/tests/test_viz.py
+++ b/tests/test_viz.py
@@ -11,6 +11,11 @@
 from common import run_tests
 from tempfile import mktemp
 
+# Prevent displaying figures
+import matplotlib as mpl
+backend_ =  mpl.get_backend() 
+mpl.use("Agg")  
+
 import numpy as np
 import numpy.testing as nptest
 
@@ -30,6 +35,7 @@ def tearDown(self):
     def test_plot_example(self):
         filename = mktemp(suffix='.png')
         for img in self.imgs:
+            ants.plot(img)
             ants.plot(img, filename=filename)
 
 class TestModule_plot_ortho(unittest.TestCase):
@@ -44,6 +50,7 @@ def tearDown(self):
     def test_plot_example(self):
         filename = mktemp(suffix='.png')
         for img in self.imgs:
+            ants.plot_ortho(img)
             ants.plot_ortho(img, filename=filename)
 
 class TestModule_plot_ortho_stack(unittest.TestCase):
@@ -56,7 +63,23 @@ def tearDown(self):
 
     def test_plot_example(self):
         filename = mktemp(suffix='.png')
+        ants.plot_ortho_stack([self.img, self.img])
         ants.plot_ortho_stack([self.img, self.img], filename=filename)
 
+class TestModule_plot_hist(unittest.TestCase):
+
+    def setUp(self):
+        img2d = ants.image_read(ants.get_ants_data('r16'))
+        img3d = ants.image_read(ants.get_ants_data('mni'))
+        self.imgs = [img2d, img3d]
+
+    def tearDown(self):
+        pass
+
+    def test_plot_example(self):
+        filename = mktemp(suffix='.png')
+        for img in self.imgs:
+            ants.plot_hist(img)
+        
 if __name__ == '__main__':
-    run_tests()
\ No newline at end of file
+    run_tests()