Hassett et al.'s biological core study on monkey toy preference

Question 1

Assumptions of the biological approach and how they relate to this core study

Answer 1

One of the main assumptions of the biological approach is behaviors can be explained in terms of the workings of the brain, the nervous system and the effects of hormones, genetics and evolution. This study demonstrated that the different hormones produced by the different genders have an impact on the behavior of toy preferences between male and female monkeys.

Question 2

The psychology that is being investigated

Answer 2

• sex differences: investigating differences in behavior versus males and females, biological factors being hormones and brain function.
• Socialisation social processes that may change the behavior of an organism
• Play and activity preferences
• The role of hormones: testosterone is a males hormone linked to aggression, libido, and the production of red blood cells . Estrogen is the female hormone, linked to the female reproductive cycle.

Question 3

Define Play

Answer 3

Pleasure gained in self-expression.

Question 4

Define Animal Play

Answer 4

• An activity voluntarily and repeatedly done by animals as a form of enjoyment and self-expression.
• Play may be adaptive, and it can help individuals practice skills required for adulthood

Question 5

The background

Answer 5

• sex differences in toy choice between humansis evident.
• Some speculate this is because of hormones and features that fulfill needs of children such as cradling and manipulation.
• Girls with congenital adrenal hyperplasia produce excess adrenal androgens, these CAH girls often prefer masculine toys.
• A study using vervet monkeys had been conducted, but measured the amount of time each type of toy was played with, not directly measuring the monkeys choice.

Question 6

The aims

Answer 6

• Investigate sex differences in toy prefereces of rhesus monkeys
• See if socialisation porcesses or biological mechnisms affect sex sterotypical toy choice in rhesus monkeys
• If sex differnces in toy choice of rhesus monkeys compared to human children

“To see if there are sex diffrences in rhesus monkeys’ preference for human gendered-stereotyped toyas as seen in humans”

Question 7

The procedures

Answer 7

• 7 25 mins trials completed
• before every trial one monkey would wait in the indoor portion of their enclosure and wait as the researcher replaced one wheeled and one plush toy 10 meters apart.
• The left or right placement of male and female toys was counterbalanced and randomly switched throughout the experiment.
• The monkeys were then let outside, and monitored via 2 cameras, one pointed towards each toy.
• After each 25 minute trial, two observers watched the recordings of the monkeys, and used a behavioral checklist to gather quantitative data regarding interaction that the monkeys had with each type of toy.
• Some of the behaviors on the checklist were extended touch (place hand or foot on toy), sit on toy (seated on or part of toy), put toy in mouth, and throw.
• Each behavior on the checklist was defined.
• One trial was stopped afte 7 minutes because a monkey destroyed a plush toy.

Question 8

The research method used

Answer 8

Experiment/ field observation

Question 9

Materials

Answer 9

• 6 wheeled toys as males toys, dumptrucks and construction vehicles.
• 7 plush toys as female toys, stuffed winnie the pooh and teddy bear.

Question 10

The number of participants and where they were from

Answer 10

• 82 monkeys
• 21 males
• rhesus monkeys
• Station for together over 25 years

Question 11

original sample and why not included

Answer 11

• 135 original rhesus monkeys
• 14 excluded due to hormonal thearpies
• 39 too young and no indentifable

Question 12

The experimental design used

Answer 12

Independent measurse

Question 13

Toy placement was counterbalanced across trials to control for location bias. what is location bias?

Answer 13

a tendency towards a particular location or certain area

Question 14

Data collection method used

Answer 14

• A video camera was focused on each toy to record interactions.
• 2 observers watched the videos and used a behavioural checklist to categorise the behaviour of the monkeys
• The start and finish time of each interaction, and from this they calculated the duration. The monkey’s age, sex, and rank.
• Not all individuals interacted with a toy (no data set for them). Those with less than 5 recorded behaviors were not used for data analysis

Question 15

What is a strength of the way data was collected?

Answer 15

One strength of that method is participants only preform one condition of the IV and so helps to eliminate order effects.

Question 16

What was a weakness of the way data was collect?

Answer 16

weakness, even though 2 researchers are investigating the study which increases inter observer reliability the researchers are both very familiar with the monkeys so their knowledge of their gender could have biased their observations.

Question 17

Independent and dependent variables used

Answer 17

Independet

• The sex of the monkey (male or female).

Dependent

• Frequency of interaction with wheeled or plush toy
• Duration of interaction with wheeled or plush toys
• Magnitude of preference score

Whether the monkeys interacted more with plush toys or wheeled toys.

Question 18

Ethical issues

Answer 18

• 25 x 25 meter outdoor with controlled temp (cause the monkeys as little stress as possible to prevent extraneous variables.)
• Water always available fed chow 2x a day once a day fruit and vegetables
• Conducted with rules set by NIH

Question 19

Why was a correlation of social rank and total frequency of interactions conducted?

Answer 19

To see whether social rank affected how long the monkey played with the sex-stereotypical toys

Question 20

Results

Quantitative/qualitative data & how it is represented and interpeted

Answer 20

Qualitative

• Males preferred wheeled toys (73%) to plush toys (9%) significantly
• Females showed no significant preference for either type of toy (30% for plush and 39% wheeled toys)

Qualitive

• toy preferences in humans and monkeys are influenced by hormonal differences.

Question 21

Social Rank Results

Answer 21

A significant positive correlation between social rank (dominance of monkeys) and frequency of interaction was found.
- Higher-ranking monkeys interacted more with the toys.
- Female monkeys who preferred plush toys had a higher rank than those who had no preference.

Question 22

Conclusion drawn

Answer 22

Toy preference in monkeys appears to be related to behavioral and cognitive biases influenced by hormones, which are affected by some social processes

Question 23

Average Duration of Interaction

Answer 23

• Males interacted with wheeled toys for a significantly longer duration than with plush toys.
• Females showed similar durations of interaction with both toy types, with a slightly longer duration for plush toys.

Question 24

Strengths
Methodological issues:

Reserach method, reliabilty,validty,generalibily,& control of variables

Answer 24

• Using the operationalised behavioural checklist increased the validity and reliability of results, as it guided researchers on how to record observations in the same way. For example, the behaviour ‘sit on’ was described as sitting on or part of a toy.
• Different pairs of toys were used on each trial, and this increased the validity as we can determine that males were drawn to wheeled toys in general, and not just a specific wheeled toy.
  - Inter-Observer Reliability reduced the risk of observer bias and meant that data could be checked for reliability

Question 25

**Weakness** Methodological Issues | Reserach method, reliabilty,validty,generalibily,& control of variables

Answer 25

- he standardised procedure was abandoned for a trial because a monkey tore a plush toy causing the trial to be stopped 7 minutes early. This reduces the **reliability** of results. - **Ecological validity** is low because the sample consisted of monkeys in captivity, and they might be more likely to show interest in new objects in their environment. Therefore, we can’t entirely generalise results to explain if wild monkeys behave in the same way. **mundane realism** - **Validity** is low because, in each trial, a group of monkeys were sent out. So if one monkey occupied the wheeled toy, another monkey wanting to play with a toy would go to the plush toy regardless of their personal preference.

Question 26

Everyday Life | The issues of application of psychology and how it realtes to the study

Answer 26

* Useful for toy companies and design to increase sales. Boys toys with wheels and girls toys can be more vaired with soft fillings and other materials * Helpful in rhesus monkeys rehabilitation from the wild. Toys could be used to improve bonding and cohesion within a group. Vaunrable monkeys may want toys for comfort and should be provided.

Question 27

Individual and Situational explanations debate | how it realtes to the study

Answer 27

**Individual** * Some monkeys were not used in final because they showed little interaction with the toys **Situational** - Monkeys placed in a noval and potential exciting situation - Situation encouraged toy choice and interactions with toys

Question 28

Nature vs. Nurture Debate | how it realtes to the study

Answer 28

**Nature** * finding showed that without soicalisation period male monkeys chose masculine types toys and females chose range of toys. * Similar to the study of children it can be argued there are common biological mechanisms affecting behaviours of m and **Nurture** * Not all rhesus monkets played exclusivly with masculine or feminine-type toys. * Maybe some aspectec of upbrinigns like pyschological mechinims such as socail learning or operant conditioning.

Question 29

Use of animals | In psychological research and how it realtes to the each study

Answer 29

* In according with NIH guid for care and use of lab animals * monkeys already invloved in envirmoental enrichemtn in Yerkes Center * Had diet access and lived in social groups