Equipment
The task runs in a standard five-hole box (or nine-hole box using only five holes):
Task details
The task is a series of n trials. Each trial has the following format:
| • | Attention phase (phase 1). Light presented in one of five spatial locations. Wait for rat to detect/acknowledge by nosepoking in that hole. Success → delay phase. Failure within limited hold period (failure to respond, or responding in the wrong hole) → darkness. (Optionally, premature responding also leads to the end of the trial and darkness.) |
| • | Delay phase. Darkness. |
| • | Choice phase (phase 2). Original stimulus ± one or more distractors presented. In the MATCHING task, rat must choose the location of the previous stimulus (success → reward; failure → end of trial and darkness). In NON-MATCHING task, these contingencies are reversed (i.e. responding to any hole that was illuminated, but was not the Phase 1 hole, is rewarded). |
| • | Intertrial interval (ITI). Darkness. |
There is an overall session time limit. If this expires, the ongoing trial isn't aborted but the task finishes when the current trial is done.
Trial format in detail
Think of the task as existing in a number of states, because that's how the program implements it. Incidentally, this is an exercise in mental discipline: if you can't specify a state table like this, having thought about what should happen in response to all possible events in any state, then you can't program the task properly.
Blue text shows the states that a successful subject passes through.
State name |
Description |
State of the box |
Consequence of nosepoking at the front panel (one of the five holes) |
Consequence of nosepoking at the rear (food) panel |
Consequence of time passing |
PHASE_NOTSTARTED |
"Not started yet". Awaiting experimenter to start task. |
Darkness. |
- |
- |
- |
PHASE_WANTPANELPUSH |
"Awaiting panel-push". |
Houselight on. |
Recorded. No other consequence. |
Recorded. Go to PHASE_INITIAL_PAUSE. |
-. Note potential for long pause. |
PHASE_INITIAL_PAUSE |
"Initial pre-stim pause". |
Houselight on. |
Recorded (anticipatory nosepoke). No other consequence unless user has chosen to punish these (m_bPunishPhase1Premature), in which case go to PHASE_DARKNESS. |
Recorded (panel push in initial pause). No other consequence. |
Go to PHASE_STIM1_ON. |
PHASE_STIM1_ON |
"Stimulus 1 on". |
Houselight on. Stimulus light on. |
If correct response, go to PHASE_DELAY (and if rewarding phase 1, also deliver pellets). If incorrect response, go to PHASE_DARKNESS. |
Recorded. No other consequence. |
Go to PHASE_STIM1_DONE. |
PHASE_STIM1_DONE |
"Stimulus 1 done, a/w response". |
Houselight on. Stimulus off. |
Exactly as for PHASE_STIM1_ON. |
Recorded. No other consequence. |
Limited hold expired; score Phase 1 omission; go to PHASE_DARKNESS. |
PHASE_DARKNESS |
"DARKNESS... New trial". |
Darkness. |
Recorded. No other consequence. |
Recorded. No other consequence. |
Go to PHASE_WANTPANELPUSH. |
PHASE_DELAY |
"Memory delay". |
Houselight on, or if selected, flashing houselight distractor. Traylight on. |
Recorded (perseverative nosepoke). No other consequence. |
Recorded (panel push during delay). No other consequence. |
Go to PHASE_DELAYDONE. |
PHASE_DELAYDONE |
"Delay finished. Now poke!" |
Exactly as for PHASE_DELAY. |
Exactly as for PHASE_DELAY. |
Recorded (without any special label). Go to PHASE_STIM2_ON. |
-. Note potential for long pause. |
PHASE_STIM2_ON |
"Choice stimuli". |
Houselight on. Traylight off. Choice stimuli on. |
If correct response, give reward and go to PHASE_COLLECTING_BIGBONUS. If incorrect response, go to PHASE_DARKNESS. |
Recorded. No other consequence. |
Go to PHASE_STIM2_DONE. |
PHASE_STIM2_DONE |
"Stimulus 2 done, a/w response". |
Houselight on. Traylight off. Choice stimuli off. |
Exactly as for PHASE_STIM2_ON. |
Recorded. No other consequence. |
Limited hold expired; score Phase 2 omission; go to PHASE_DARKNESS. |
PHASE_COLLECTING_BIGBONUS |
"You won. Eat up." |
Houselight on. Traylight off. |
Recorded. No other consequence. |
Recorded. Go to PHASE_EATING_UP. |
-. Note potential for long pause. |
PHASE_EATING_UP |
"Munch. Munch. Munch." |
Houselight on. Traylight off. |
Recorded. No other consequence. |
Recorded. No other consequence. |
After end of eating time, go to PHASE_DARKNESS. |
FINISHED |
"--- Finished. ---" Rat finished the task. |
Darkness. |
- |
- |
- |
ABORTED |
"*** Aborted! ***" User aborted the task. |
Darkness. |
- |
- |
- |