Temperature’s Impact on Cognitive Capabilities

Creative Collaborative Science Fair Project

Authors: Kamran Shukoor, Rameez Nasir, Salma Sher, Ibrahim Tariq, Akhtar Ghanni-Khan, Rafee Chowdhary, Rustom Alghoul

Findings Published in: MediUnite and MediUnite Journal, Local Science Fair (Name Withheld)

Abstract

Cognitive abilities are the fundamental abilities required to complete a process as a human (Sternberg and Sternberg, 2009). Any change to its capabilities can be evidently demonstrated through basic tests of a mental state exam including Stroop Test(s), Digit Span Test(s), Reaction Time Test(s), as well as others. The theory of thermal determinism, has long been theorised to have a direct effect on cognitive ability, sometimes linked to the competency of figureheads, and hence rise and downfall of empires from the 12th-19th century. One example suggests the rise of the Mongol empire in the 12th century was correlated to the increased cognitive ability of Genghis Khan and his associates, following a colder, rainy period in the regions around what is now known as Mongolia. Though there is little evidence to suggest so, the theory of thermal determinism continues to be explored in the era of modern science, and in recent years, has gained traction because of its potential implications. Today, it theoretically disproportionately serves individuals living in developing nations, 112 of which are warmer on average, than almost all first-world nations. Lower cognitive ability carries immense weight on a large scale of an entire community or nation, in terms of productivity, economic growth, infrastructure, and various others. UNCTAD’s Productive Capacities Index (PCI) proves that almost all of the least developed countries (LDC’s) have an average of 40% lower PCI levels than that of LDC’s. Similarly, the prevalence of lower productivity, lower economic growth, and poor infrastructure are more often in LDC’s, once again, 112 of which consistently face higher average temperatures. Hence, it is crucial we acknowledge the disproportionate disadvantage faced by those in warmer, often less developed countries face, and may continue to increasingly disproportionately face as a result of global climate change.

Introduction

1. Abstract
2. Background and Executive Summary
3. Investigative Question
4. Literature Review
5. Methodology
6. Presentation of Data
7. Data Analysis
8. Comparison with Formal Research
9. Psychological and Physiological Implications
10. Limitations
11. Conclusion
12. References

Executive Summary

Overview of Temperature’s Cognitive Impact

Temperature has long been suspected to directly exert a significant influence on cognitive function. Studies of psychology and neuroscience have long underscored the significance of temperature variations in affecting mood, attention, and memory. Acknowledging the consequential relationship between temperature and cognitive capabilities is of paramount importance in daily life and decision-making processes. From urban planning, policy-making, and even healthcare, optimising environmental conditions can potentially enhance patient outcomes. The Medical Facilities Efficiency Report (2020) reported a 15% reduction in recovery times observed in hospitals maintaining temperatures within the optimal range for cognitive function (later defined). The degree to which temperature plays that role is what this project aims to answer.

Literature Review

An examination of existing research will be conducted to establish a comprehensive understanding of the impact of temperature on cognitive function. The analysis will encompass literature in schools of psychology, neuroscience, and environmental science.

Experimentation

Experimentation and data collection was conducted across diverse regions and climates, primarily including northern and central regions of Pakistan, and northern Afghanistan (spanning 3 months to vary climate and weather), as well as a diverse group of cities to avoid bias, including Calgary, Seattle, Doha, and Chicago and various parts of Khyber Pakhtunkhwa (KPK) and North Afghanistan. Cognitive performance was assessed through 3 specific standardised tests, with a focus on tasks related to mood, attention, memory, and decision-making.

Data Collection and Comparative Analysis

Local temperature data was collected from reliable sources to correlate with cognitive performance. Various comparisons to formal research have been made to identify such relationships and quantify the impact of temperature on cognitive capabilities.

Key Findings

Mood and Alertness:

Both Martinez et al. (2019), and Thompson (2020), indicate that mild to cold temperatures tend to be associated with reduced mood levels and reduced alertness. Martinez et al. observed a 30% decrease in self-reported mood scores in participants exposed to temperatures considered too hot or too cold compared to room relative temperature. Further, Thompson’s study revealed a 20% reduction in alertness levels under identical conditions.

Attention and Focus:

Johnson and Lee (2017) suggest that extreme temperatures, both hot and cold, are likely to lead to diminished attention and focus levels. Participants exposed to temperatures exceeding 30°C, exhibited 25% lower levels in sustained attention, while those in conditions below 10°C demonstrated a 20% decrease in focused attention.

Memory Retention:

Chen et al. (2020) suggest that moderate temperatures are conducive to optimal memory retention, while extreme temperatures are highly likely to impair this cognitive function. Participants in conditions ranging from 20–25°C exhibited 35% higher levels of memory retention compared to those in conditions exceeding 30°C or below 10°C.

Decision-Making:

Harper and Rodriguez (2021) suggest that the influence of temperature on decision-making processes. Colder temperatures were associated with a 17% increase in risk aversion, with the opposite true for colder temperatures.

Physiological Mechanisms:

(Garcia et al., 2018; Li and Wang, 2019) suggest that neurological and hormonal factors play a substantial role in mediating the impact of temperature on cognitive function. Garcia et al.’s neuroimaging study demonstrated a 40% increase in prefrontal cortex activation in response to a 5°C temperature rise, highlighting the intricate neural processes involved. Li and Wang’s investigation also revealed a 25% reduction in stress hormone secretion levels during optimal temperature conditions (universal room temperature).

Additional Acknowledgements:

The findings carry practical implications for a multitude of fields, including healthcare, urban planning, and policy-making, ultimately contributing to enhanced well-being and decision-making processes in varying environmental conditions. This project was made possible through the collaboration of MediUnite and the invaluable contributions of MediUnite Journal, particularly in conducting experimentation in remote parts of the world. We have obtained informed consent, and implementing privacy and data protection protocols

Literature Review: The Impact of Temperature on Cognitive Ability

Psychological Perspectives:

Hancock’s seminal work (1986) on the effects of temperature on cognitive performance demonstrates that participants exposed to hot conditions exhibited a 40% reduction in sustained attention, leading to 25% slower response times. Furthermore, in tasks necessitating problem-solving, error rates rose by 30% under high-temperature conditions. This decreased cognitive function in high temperature conditions evidently underscore the vulnerability of cognitive processes to thermal variations. Schmeichel et al.’s study (2003) reinforces these findings, reporting that participants exposed to cold conditions exhibited, at a minimum, 20% reduction in working memory capacity; Meanwhile, response times in working memory tasks increased by 15% in colder conditions. Kim et al.’s study (2017), examining the correlation between seasonal variations and cognitive performance revealed an increase of 12.5% in cognitive test scores during milder seasons compared to colder months. When isolating temperature as the main variable, the study further found a positive linear relationship between temperature and cognitive abilities, with a 2.3% increase in cognitive scores for every 1°C rise in temperature. Nguyen and Smith’s longitudinal investigation over a five-year period (2018), found that participants exposed to extreme climates exhibited a 17.8% decline in cognitive functioning, particularly in tasks related to working memory and information processing speed.

Psychological Mechanisms: Mood, Attention, Memory

Hartley et al.’s study (2019) exhibited a 28.6% improvement in attention and memory tasks in participants with elevated mood, compared to those with neutral or negative affect. This finding supports Isen et al. ‘s findings (1987), that positive affect serves as a facilitator for cognitive functioning. Hence, Harper and Rodriguez’s study (2021) on attentional processes reported that in tasks requiring sustained attention, participants exhibited a 15.2% decrease in performance during temperature variations exceeding 10°C within a short time frame. This finding corroborates established research from Stephen Kaplan’s “Attention Restoration Theory” (1995).

Physiological Mechanisms: Neurological and Hormonal

Martinez and Lee’s study (2019) on hormonal responses to temperature variations revealed a 12.4% increase in alertness levels and a 9.7% decrease in stress hormone secretion during optimal temperature conditions.

Neuroscientific Perspectives:

C. J. Gordon’s 1990 study on temperature regulation in laboratory rodents provides detailed neurophysiological evidence. Gordon’s experiments demonstrated that extreme temperatures prolonged synaptic response times by up to 50%, resulting in a substantial reduction in information processing speed. Additionally, alterations in neurotransmitter levels, including a 30% decrease in dopamine release, were observed. Han et al.’s review (2019) suggests, through neuroimaging findings, a “significant decrease” in prefrontal cortex activation during tasks requiring cognitive control. This reduction in activation was most pronounced in tasks necessitating inhibitory control and attentional switching. Zhang et al.’s neuroimaging based study (2020), identified distinct activation patterns in the prefrontal cortex and hippocampus associated with temperature modulation. Specifically, rounded to the nearest whole percent, an 8% increase in neural activity was observed in response to temperature increments of 5°C.

Environmental Perspectives:

Burke, Hsiang, and Miguel’s seminal study (2015) on the economic consequences of temperature variations demonstrates that a 1°C increase in temperature above historical averages led to a substantial 1.2% reduction in overall economic output. Meanwhile, Stone Jr. et al.’s study (2015) on urban heat islands incorporates an extensive survey of residential energy use patterns. The study revealed that densely populated urban areas experience temperature differentials of up to 10°C compared to nearby rural regions. This pronounced urban heat effect translates to a notable 25% increase in energy consumption for cooling, thereby exacerbating the cognitive challenges posed by temperature variations.

Methodology:

Our project employed a longitudinal design spanning a total of 3 months. The project used elements of a Randomised Controlled Trial to help establish relationships between temperature variations and cognitive performance.

Data Collection:

• Daily Cognitive Assessments: Standardised tests focusing on mood, attention, memory, and decision-making will be administered to participants on a daily basis. These assessments serve as the primary means of evaluating cognitive capabilities throughout the period of 3 months.
• Consistent Temperature Data Collection: Local meteorological stations were the primary source of consistent temperature data during hours of data collection. This data will include temperature, humidity, and barometric pressure.

Participants:

A cohort of just over 100 participants (specifically 117), aged between 25 and 65, will be recruited for this project. Participants were selected from diverse and random backgrounds to isolate the manipulated variable for temperature as much as possible. Prior to participation, informed consent was obtained from all participants, and demographic data has been taken into consideration.

Temperature Data Sources:

The project relied on meteorological data provided locally. Data was collected at regular intervals to accurately encompass key variables, notably temperature, humidity, wind, and barometric pressure.

Cognitive Assessment Tools:

The following standardised tests were be employed to evaluate various facets of cognitive performance:

• Mini-Mental State Examination(s) or (MMSE): This widely recognized assessment tool will be utilised to gauge global cognitive functioning, providing an initial snapshot of participants’ cognitive state.
• Stroop Test(s): This test will assess attention, cognitive flexibility, and processing speed. Participants will be tasked with naming the colour of a word while ignoring the actual word itself.
• Digit Span Test(s): This test will measure working memory capacity. Participants will be required to repeat a sequence of numbers, either forwards or backwards.
• Trail-Making Test(s): This test assessed visual attention and task-switching ability. Participants will be asked to connect a series of numbered items in their respective order as fast as possible.

Privacy and Data Protection:

Protocols have been implemented to safeguard participant privacy and protect their sensitive information, hence some data may be limited for public exposure.

Reliability and Validity:

• Calibration and Validation of Cognitive Tests: Prior to the commencement of the project, all cognitive tests have been investigated for their historical reliability and validity, and hence in the context of this investigation.
• Statistical Validation of Temperature Data: Temperature data obtained from local meteorological stations was subjected to validation from remote temperature sources to ensure accuracy and reliability.

Specific Methodological Considerations:

• Controlling for Confounding Variables: Potential confounding variables, including sleep patterns, dietary habits, and pre-existing health conditions, will be carefully taken into consideration to isolate the effect of temperature on cognitive capabilities.
• Blinding: Both assessors and participants will be blinded to the hypotheses and existing findings of the project to minimise bias in the assessment process.
• Data Quality Control Measures: Data quality control measures were implemented to ensure accuracy, completeness, and consistency in the collection and storage of both cognitive and thermal data.

Presentation of Data:

Disclaimer: In order to protect the privacy of the participants, some data may be limited from public exposure. Simplified versions may be given, while other forms of representation have been hidden.

Table 1: Comparative Analysis of Cognitive Performance Against Temperature Difference of 5 Degrees Respectively (Simplified)

*Determination of the Mean Cognitive Score was concluded on the basis of scoring cognitive tests in terms of the number of cognitive tests passed, timing, and the degree of accuracy and reliability. Scores were determined to the nearest tenth due to the nature of the tests and determination of the mean cognitive score.

Bar Chart 1: Comparative Analysis of Timed Cognitive Performance (Depth) Across 6 Unique Countries vs Assessed Temperature

Data Analysis:

General:

A mild effect of temperature conditions on cognitive performance is revealed.

Attention Span:

Participants exhibited the highest mean attention span score on cooler days* (88.6), followed by days with milder temperatures** (85.4) and warmer days*** (80.2). These results substantiate prior research and literary works, indicating that extreme cold and warm temperatures may negatively influence attention.

Response Time:

As anticipated, response times were quickest on cooler days* (mean = 87.2), followed by days with milder temperatures* (mean = 85.4) and warmer days* (mean = 82.1). The influence of warmer temperatures on slower reaction times aligns with existing literature, previously cited, and further discussed.

Other factors like memory retention, problem solving, and more were also taken into account (HIDDEN).

*Cooler days: 10°C to 20°C

**Milder days: 20°C to 30°C

***Warmer days: 30°C and above

Comparison with Formal Research:

Jes Cús Cudeiro, David Soto, and Emilio Gutiérrez performed a pre-registered replication test (2023), where the effects of heat were isolated into two sections of 50°C and 28°C. 60 participants, aged 21–29, were assigned to one of the two temperatures inside separate saunas. Participants performed with greater accuracy in the 28°C environment.

Wyon, D P et al.’s research (1979) found that performances in several cognitive tests peaked near 27°C. Slight increases above optimum temperature were associated with having adverse impacts on mental performance, disproportionately more in males.

Hancock PA.’s “Heat stress impairment of mental performance: a revision of tolerance limits” (1981) proved a significant difference between simple tasks and motor tasks in heat. Exposure to heat for simple and mental tasks did not induce sufficient effects, while in contrast the effects on perceptual motor tasks were significant and proved to decrease due to high temperatures.

5 years later in 1986, Hancock’s “Heat Stress Impairs Mood, Cognition, and EEG” (1986) investigated the effects of heat stress on cognitive performance. Participants exposed to high temperatures exhibited a decrease in attention span, slower response times, and reduced problem-solving abilities. The study also noted a decline in memory retention in warmer conditions.

Eggenberger, Patrick; Bürgisser, Michael; Rossi, René M.; Annaheim, Simon. (2021), studied the effects of temperature on the cognitive performance of the elderly. They concluded that increased temperature inversely correlated to verbal fluency, memory, processing, and functioning ability.

Qi Zhao, Claudia Wigmann, Ashtyn Tracey Areal, Hicran Altug, Tamara Schikowski (2021), studied the effects of non-optimum ambient temperature on the SALIA cohort in Germany. A decline of cognitive functioning was strongly tied to higher temperatures.

“The Effect of Temperature on Cognitive Performance” by Lenhardt et al. (2009) found that as temperatures increased, participants demonstrated decreased attention span, longer response times, and diminished problem-solving skills. Memory retention was also negatively affected by higher temperatures.

“Heat Stress and Open-Water Survival: The Psychophysics of Prolonged Immersion” by Cain et al. (2011) observed that participants experienced reduced attention spans, slower response times, and impaired problem-solving abilities as temperatures rose. Memory retention was negatively affected by prolonged exposure to higher temperatures.

Psychological and Physiological Implications:

“Impact of Heat Stress on Cognitive Performance in Mining Workers” by Mallick et al. (2020), focused on a specific occupational context, this study assessed the cognitive performance of mining workers exposed to high temperatures. The results indicated a negative correlation between temperature and cognitive abilities. Higher temperatures were associated with reduced attention span, slower response times, compromised problem-solving skills, and impaired memory retention. These findings are further supported by Rosenthal et al.’s research (1984), and later, Keller et al.’s research (2005), linking temperature and climate’s role in increased feelings of sadness and depression, clinically described as Seasonal Affective Disorder.

Limitations:

1. Generalisation to Specific Contexts: The project was conducted in select countries and cities across the world, with a specialisation to Northern Afghanistan and Mid to North Pakistan, which may not fully reflect the complexities of the wider world. It’s important to recognize that the impact of temperature on cognitive abilities may vary in different contexts, such as outdoor environments or workplaces with varying levels of climate control, as well as other related factors like wind, level of direct sun, length of days, humidity, and countless others.
2. Potential Confounding Variables: While efforts were made to control for potential confounding variables, it is difficult to determine the influence of external factors that were taken into consideration, as well as the influence of those not accounted for in this project. Variables like individual differences in acclimatisation to temperature or variations in hydration levels certainly play an important role.
3. Subjective Measures of Cognitive Performance: The project relied on standardised cognitive tests, which may not fully capture all aspects of cognitive abilities. Further, participants self-reported their comfort levels within the context of different temperatures, which is of a subjective nature itself.
4. Extraneous Environmental Factors: While efforts were made to control the environment, there may be other unmeasured variables that could have influenced cognitive performance. These factors should be considered moving forwards.

Conclusion

Summary of Key Findings:

Previous research supports our findings, more or less, a noteworthy trend: as temperatures rise or fall to the extremes, cognitive abilities tend to exhibit a decline. Notably, attention span and problem solving abilities exhibit significant sensitivity to changes in temperature. Memory retention, though exhibiting unexpected fluctuations highly likely due to external factors, also revealed a nuanced relationship with environmental temperature.

Theoretical and Practical Implications:

Understanding the impact of temperature on cognitive abilities holds significant theoretical and practical importance. In daily life, individuals often find themselves navigating diverse thermal environments. Recognizing how temperature influences cognitive capabilities can inform decisions related to work, leisure, and overall well-being. Acknowledgement for the decreased cognitive abilities in extreme temperature areas, especially in critical contexts like healthcare, becomes paramount in providing healthy conditions and “workable” environments. Whether in the workplace, educational institutions, or healthcare facilities, optimising environmental conditions can have a tangible impact on cognitive performance and, consequently, overall productivity and quality of life across diverse demographics.

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