diff --git a/core/templates/dev/head/domain/exploration/ParamTypeObjectFactory.ts b/core/templates/dev/head/domain/exploration/ParamTypeObjectFactory.ts
index b9392d862b44..efa9bf275c13 100644
--- a/core/templates/dev/head/domain/exploration/ParamTypeObjectFactory.ts
+++ b/core/templates/dev/head/domain/exploration/ParamTypeObjectFactory.ts
@@ -124,7 +124,7 @@ export class ParamTypeObjectFactory {
     // The bracket notation is needed since 'backendName' is a dynamic property
     // and is not defined on 'registry'.
     /* eslint-disable dot-notation */
-    return this.registry['backendName'];
+    return this.registry[backendName];
     /* eslint-enable dot-notation */
   }
 }
diff --git a/core/templates/dev/head/domain/exploration/ParamTypeObjectFactorySpec.ts b/core/templates/dev/head/domain/exploration/ParamTypeObjectFactorySpec.ts
index 8d691369f9c8..ed3afc62324f 100644
--- a/core/templates/dev/head/domain/exploration/ParamTypeObjectFactorySpec.ts
+++ b/core/templates/dev/head/domain/exploration/ParamTypeObjectFactorySpec.ts
@@ -34,6 +34,12 @@ describe('ParamType objects', () => {
     expect(paramType.getDefaultType()).toBe(paramType.registry.UnicodeString);
   });
 
+  it('should return correct values for existing types', () => {
+    Object.entries(paramType.registry).forEach(([backendName, value]) => {
+      expect(paramType.getTypeFromBackendName(backendName)).toEqual(value);
+    });
+  });
+
   it('should throw for non-existant types', () => {
     expect(() => {
       paramType.getTypeFromBackendName('MissingType');