diff --git a/csys/csys.lisp b/csys/csys.lisp
index 435d149..fe0720c 100644
--- a/csys/csys.lisp
+++ b/csys/csys.lisp
@@ -10,11 +10,12 @@
                     (:shape :scopes/shape)
                     (:util :scopes/util)
                     (:alx :alexandria))
-  (:export #:environment #:*environment* #:detectors
+  (:export #:environment #:*environment* #:effectors
            #:init
            #:send #:send-message
            #:neuron #:synapse
-           #:create-neuron #:update-neuron))
+           #:make-neuron #:update-neuron 
+           #:handle-action))
 
 (in-package :scopes/csys)
 
@@ -24,17 +25,15 @@
   ((actions :reader actions :initarg :actions :initform (make-hash-table))
    (sensors :reader sensors :initarg :sensors 
             :initform (make-hash-table :test #'equal))
-   (detectors :reader detectors :initarg :detectors
+   (effectors :reader effectors :initarg :effectors
               :initform (make-hash-table :test #'equal))))
 
 (defvar *environment* (make-instance 'environment))
 
-(defun init (&optional probe)
+(defun init (zero)
   (setf (gethash :sensor (actions *environment*)) #'create-sensor)
-  (let* ((default-det (or probe (actor:create (neuron #'do-log))))
-         (zero (make-neuron default-det :state 0)))
-    (setf (gethash '(:init :zero) (sensors *environment*)) (list zero))
-    (setf (gethash :default (detectors *environment*)) (list default-det))))
+  (setf (gethash '(:init :zero) (sensors *environment*)) (list zero))
+  (setf (gethash :default (effectors *environment*)) (list zero)))
 
 ;;;; sensors: neurons receiving messages from environment, addressable via message head
 
@@ -58,9 +57,9 @@
 (defun do-log (msg state syns env)
   (util:lgi msg))
 
-(defun find-detectors (key &optional (default-key :default) (env *environment*))
-  (let ((dts (detectors env)))
-    (gethash key dts (gethash default-key dts))))
+(defun find-effectors (key &optional (default-key :default) (env *environment*))
+  (let ((effs (effectors env)))
+    (gethash key effs (gethash default-key effs))))
 
 ;;;; neurons (= behavior factories) and synapses (connection factories)
 
@@ -74,7 +73,8 @@
 
 (defun make-neuron (syn-target &key (proc #'std-proc) state 
                                (syn-op #'identity) (env *environment*))
-  (actor:create (neuron proc state (list (synapse syn-target syn-op)) env)))
+  (let ((syns (if syn-target (list (synapse syn-target syn-op)) nil)))
+    (actor:create (neuron proc state syns env))))
 
 (defun update-neuron (proc state syns &optional (env *environment*))
   (actor:become (neuron proc state syns env)))
diff --git a/test/test-csys.lisp b/test/test-csys.lisp
index d77f5ee..2fcb408 100644
--- a/test/test-csys.lisp
+++ b/test/test-csys.lisp
@@ -27,9 +27,11 @@
   (let ((t:*test-suite* (test-suite env))
         (val (shape:data msg)))
     (util:lgi msg state)
-    (unless (consp val)
-      (let ((nst (in-seq val state :remove t)))
-        (csys:update-neuron #'probe nst syns env)))))
+    (destructuring-bind (msg state syns) 
+      (csys:handle-action msg state syns env)
+      (unless (consp val)
+        (let ((nst (in-seq val state :remove t)))
+          (csys:update-neuron #'probe nst syns env))))))
 
 (defun add (msg state syns env)
   (list msg (+ (shape:data msg) state) syns env))
@@ -40,9 +42,8 @@
   (async:init)
   (let* ((t:*test-suite* (make-instance 't:test-suite :name "csys"))
          (csys:*environment* (make-instance 'test-env :test-suite t:*test-suite*))
-         (probe (actor:create 
-                  (csys:neuron #'probe '(1 3 4 5)
-                               nil csys:*environment*))))
+         (probe (csys:make-neuron nil :proc #'probe :state '(1 3 4 5)
+                                      :env csys:*environment*)))
     (load (t:test-path "config-csys" "etc"))
     (core:setup-services)
     (unwind-protect
@@ -53,7 +54,7 @@
       (t:show-result))))
 
 (deftest test-init (probe)
-  ;(setf (gethash '(:std :d0) (csys:detectors csys:*environment*)) probe)
+  ;(setf (gethash '(:std :d0) (csys:effectors csys:*environment*)) probe)
   (csys:init probe)
   (csys:send-message '(:csys :sensor :init :zero) '(:std :s1))
   (csys:send-message '(:csys :sensor :init :zero) '(:std :s2))
diff --git a/util/util.lisp b/util/util.lisp
index 84c7eee..d741ab9 100644
--- a/util/util.lisp
+++ b/util/util.lisp
@@ -31,7 +31,7 @@
 
 (defun make-vars-format (vars &optional info)
   (let ((prefix (if info (format nil "~a: " info) "")))
-    (format nil "~a~{~(~a~): ~~S ~}" prefix vars)))
+    (format nil "~a~{~(~a~): ~~A ~}" prefix vars)))
 
 (defmacro lg (level info &rest vars)
   (let ((lm (find-symbol (string level) :log))