diff --git a/activemodel/lib/active_model/dirty.rb b/activemodel/lib/active_model/dirty.rb
index 60af31cca7..337b61c55c 100644
--- a/activemodel/lib/active_model/dirty.rb
+++ b/activemodel/lib/active_model/dirty.rb
@@ -170,7 +170,7 @@ module ActiveModel
 
     # Handle <tt>*_changed?</tt> for +method_missing+.
     def attribute_changed?(attr, options = {}) #:nodoc:
-      result = changed_attributes.include?(attr)
+      result = changes_include?(attr)
       result &&= options[:to] == __send__(attr) if options.key?(:to)
       result &&= options[:from] == changed_attributes[attr] if options.key?(:from)
       result
@@ -188,6 +188,10 @@ module ActiveModel
 
     private
 
+      def changes_include?(attr_name)
+        attributes_changed_by_setter.include?(attr_name)
+      end
+
       # Removes current changes and makes them accessible through +previous_changes+.
       def changes_applied # :doc:
         @previously_changed = changes
diff --git a/activerecord/lib/active_record/attribute_methods/dirty.rb b/activerecord/lib/active_record/attribute_methods/dirty.rb
index 033e71f7b9..d5702accaf 100644
--- a/activerecord/lib/active_record/attribute_methods/dirty.rb
+++ b/activerecord/lib/active_record/attribute_methods/dirty.rb
@@ -76,6 +76,10 @@ module ActiveRecord
 
       private
 
+      def changes_include?(attr_name)
+        super || attribute_changed_in_place?(attr_name)
+      end
+
       def calculate_changes_from_defaults
         @changed_attributes = nil
         self.class.column_defaults.each do |attr, orig_value|
diff --git a/activerecord/test/cases/dirty_test.rb b/activerecord/test/cases/dirty_test.rb
index eb9b1a2d74..1eaff5e293 100644
--- a/activerecord/test/cases/dirty_test.rb
+++ b/activerecord/test/cases/dirty_test.rb
@@ -698,6 +698,21 @@ class DirtyTest < ActiveRecord::TestCase
     assert binary.changed?
   end
 
+  test "attribute_changed? doesn't compute in-place changes for unrelated attributes" do
+    test_type_class = Class.new(ActiveRecord::Type::Value) do
+      define_method(:changed_in_place?) do |*|
+        raise
+      end
+    end
+    klass = Class.new(ActiveRecord::Base) do
+      self.table_name = 'people'
+      attribute :foo, test_type_class.new
+    end
+
+    model = klass.new(first_name: "Jim")
+    assert model.first_name_changed?
+  end
+
   private
     def with_partial_writes(klass, on = true)
       old = klass.partial_writes?