CEU Event
Eb Blakely, Ph.D., BCBA-D
Ansley Hodges, M.S., BCBA
Signs of Damage: Skinner
 From "Contingencies of Reinforcement"
 Page 51: "The principle also holds for aggressive behavior. At a time when
men were often plundered and killed, by animals and other men, it was
important that any behavior which harmed or frightened predators should be
quickly learned and long sustained. Those who were most strongly
reinforced by evidences of damage to others should have been most likely to
survive."
 Page 129: "A person who is at the moment aggressive is one who, among
other characteristics, shows a heightened probability of behaving verbally or
nonverbally in such a way that someone is damaged..."
 Page 195: "Azrin, for example, has studied the stereotyped, mutually
aggressive behavior evoked when two organisms receive brief electric
shocks. But he and his associates have also demonstrated that the
opportunity to engage in such behavior functions as a reinforcer and, as
such, may be used to shape an indefinite number of "aggressive" operants
of arbitrary topographies. Evidence of damage to others may be reinforcing
for phylogenic reasons because it is associated with competitive survival.
Competition in the current environment may make it reinforcing for ontogenic
reasons."
Signs of Damage: Stimuli
What stimuli are involved?
Visual stimuli – blood, bruising,
scratches, “upset” expressions
Auditory stimuli – crying, screaming
Response produced stimuli –
pressure on teeth, pressure on
hands/feet
Early Non-Human Research
Shock “elicited” fighting
 Subjects: Rats
 Procedure: Rats exposed to shock
 Measure: # of episodes of fighting
 Aggression was called “reflexive”
 Results: Most shocks evoked fighting
Early Non-Human Research
Shock “elicited” biting of inanimate objects
 Subjects: Rats
 Procedure: Rats exposed to shock
 Measure: # of episodes of biting of metal, wood,
or rubber targets
Early Non-Human Research
Aggression evoked by schedules of reinf
 Subjects: Pigeons
 Procedure: Ss exposed to FR 50
 Measure: # attacks to target pigeon
 Results: Most attacks occurred during PRP
Early Non-Human Research
What kind of target is the best?
 Subjects: Pigeons
 Procedure: Ss exposed to FR 80-120
 Measure: # attacks to target (Mirror, Live
protected, Stuffed)
Early Non-Human Research
Biting as a function of FR size
 Subjects: Squirrel monkeys
 Procedure: Ss exposed to FR schedules (50-200)
 Measure: # bites of a rubber hose
 Results: 1) Most biting occurred in PRP as a
function of ratio size 2) also occurred in Ext
Early Non-Human Research
Biting evoked by schedules of reinforcement
Does Effort Matter?
 Subjects: Pigeons
 Procedure: Ss exposed to
FR and yoked schedules of
free food (MT = matched
time)
 Measure: # attacks
Early Non-Human Research
Opportunity to Aggress: Is it a reinforcer?
 Subjects: Squirrel monkeys
 Procedure: Chain pulls  rubber ball to bite
 Results: Presentation of ball reinforced/maintained
chain pulls
Early Non-Human Research
Opportunity to Aggress: Is it a reinforcer?
Early Non-Human Research
Opportunity to Aggress: Is it a reinforcer?
 Subjects: Pigeons
 Procedure: 1) FI schedule for food and 2) 2nd key pecks
 access to a target pigeon
Recent Non-Human Research
Opportunity to Aggress: Is it a reinforcer?
 Subjects: Mice
 Procedure: Intruder mouse presented after completion
of FR 8 vs Ext
 Results: Concurrent food schedule not needed
Summary
 Aversive stimuli will evoke aggression
 Shock
 Reinforcement offset
 Work requirements
 Heat
 Strikes to body
 The opportunity to aggress will function as a reinforcer
for behavior
 Most likely occurs when aversive stimuli are present
 May occur in absence of such stimuli in some members of
species
Conclusions
 Aggression evoked by aversive stimuli is not a
respondent
 If operant, what reinforces it?
 Signs of damage (cf Skinner): cowering, crying, blood, running away
 Pressure on body part used to attack (e.g., teeth, fists)
 How do we talk about this?
 Signs of damage and/or related stimuli may be naturally reinforcing in
some species, or some members of a species
 EO s may be aversive events and schedules of reinforcement
 We should address this in behavioral assessment and
Tx
Implications
 Standard Functional Analyses
 Unclear results
 But naturalistic observations suggested that attention was a factor, but
attention was given in loud, emotionally-charged bouts
David M. Richman and Louis P. Hagopian
Implications
 Idiosyncratic Conditions in Functional Analysis
 Exaggerated Attention: “dramatic reaction to Tim’s destructive behaviors
that included a high level of voice intonation, verbal phrases such as “I
can’t believe that you just did that,” and physical signs of displeasure
such as waving his/her hands frantically. “
Functional Analyses Results
Case #1 FA
 Higher rates of problem behavior when caregiver
reacted “upset” than when caregiver provided a
neutral reprimand, or during no attention conditions
 Seeks out other kids crying
Case #2 FA
 Throwing items/tipping chairs increased when mom
reacted “frustrated” or “aggravated” compared to
neutral reprimands.
Case Study #3
 Descriptive assessment information
 Engages in SIB (arm scratching, and picking) during free
time that produces blood
 Looks for bruising after aggression
 Aggression is more likely in presence of aversive stimuli
(e.g., denied access to items/activities, work requirements)
 Property destruction when denied access – and would
carefully look at the item
 Would mand for item to break!
Case Study #3
Preference Assessment Over 4 Exposures
6
5
Rank
4
3
2
1
0
Blood
Water
Dora Book
Drawing
Nuts
Bandaid
Case Study #3
Reinforcer Assessment: Conc FR 1 Ext
Frequency of selecting square
10
9
= = Blood
8
= Blood
= Blood
7
6
5
4
3
2
1
0
0
1
2
3
4
Sessions
5
6
7
Case Study #3
 Tx elements
 Replacement skill:
 Select alternatives when denied access
 Waiting
 Fade in work requirements
 Mand for delay of reinforcer offset
 Calendar of when events will occur
 Extinction? Can signs of damage be withheld?
 Wear long sleeves during sessions
 Punishment – loss of items/activities/contingent exercise
Extensions
Unexplained phenomena
 “Extinction-induced” aggression – is it “reflexive?”
 Extinction as EO for signs of damage and other
concomitant stimuli
 Side effects of punishment: aggression!
 Punishment stimuli as EO for signs of damage and
other concomitant stimuli
Implications for Tx and Assessment
 Behavior Assessment
 Preference assessments
 Standard preference assessments with signs of damage stimuli
 Preference assessments in presence of aversive stimuli
 Interviews should address this Go
 Functional analyses with signs of damage




Cowering targets
“Angry” caregivers
Contingent property destruction
Objects to hit/bite (safely!)
 Tx procedures




Antecedent manipulations
Replacement skills
Concurrent schedules of reinforcement for appropriate behavior
Reduction procedures
Sample Program
Function: Signs of Damage
 Antecedent Manipulations
 Remove target - When sister hits Fred, separate
 Remove target during work requirements - Keep sister
away from Fred when she is engaged in chores
 Frequent physical games
 Have potential targets do pairing
 Wear long sleeves during sessions?
 Acquisition Skills
 Mands for physical activity
 Select alternatives when denied access
 Be willing to use large magnitude reinforcers
 Waiting programs
 Slowly increase wait time
 Especially consider waiting in divided attention situations
Sample Program
Function: Signs of Damage
 Acquisition Skills (continued)
 Task completion
 Slowly increase response requirements
 Use large magnitude reinforcers
 Consider VR instead of FR schedules
 Reduction Procedures
 Removal of targets
 Extinction: Withhold damage if possible
 Punishment?
 Side effects! Punishment maybe an EO for further signs of
damage maintained aggression
The End
Implications (continued)
 Structured Interview Questions
 Does the person seek out items to break?
 Does the person seek out blood or injury?
 After aggression, does the person attempt to see the injuries of the
victim?
 Does the behavior occur when denied access to items/activities, even
though they have not been given after the behavior?
 Does the person aggress after consuming a reinforcer for which he/she
had to work hard?
 Does the person seem to enjoy seeing others upset?
 Does the person tend to throw objects when denied access to
items/activities?
Return
Aggression as a Built-in Reinforcer
 Betta Splendens
Aggression as a Built-in Reinforcer
Round 1