IELTS Academic Practice Test 23

Habits, broadly defined as behaviours performed automatically in response to particular contextual cues, account for a surprisingly large proportion of daily human activity. Researchers estimate that a substantial share of everyday actions, from the route taken to work to the order in which one gets dressed, occur with minimal conscious deliberation, guided instead by neural patterns formed through repetition. The neurological basis of habit formation centres largely on a brain structure called the basal ganglia, which becomes increasingly involved as a behaviour is repeated in a consistent context. Early attempts at a new behaviour, such as learning to drive, require substantial conscious effort and rely heavily on the prefrontal cortex, the region associated with deliberate decision-making. With sufficient repetition, however, control gradually shifts towards the basal ganglia, allowing the behaviour to be executed with far less conscious attention, freeing cognitive resources for other tasks. This shift explains a phenomenon familiar to many: the difficulty of breaking established habits even when a person consciously wishes to change. Because habitual behaviours are triggered largely automatically by contextual cues rather than deliberate intention, simply desiring to stop a habit is often insufficient; the cue-triggered pathway remains largely intact even after motivation to change has been established. Research into habit change has increasingly focused on the concept of substitution rather than elimination. Rather than attempting to suppress an unwanted behaviour entirely, which studies suggest often proves temporary at best, more durable results tend to occur when an alternative behaviour is deliberately linked to the same contextual cue. A person wishing to reduce snacking while watching television, for example, may find greater success replacing the snack with another activity, such as a specific drink or a hand-based task, rather than attempting simply to abstain. The timeframe required to establish a new habit varies considerably between individuals and behaviours, contradicting a popular but poorly supported claim that new habits reliably form within a fixed number of days. Studies tracking real participants attempting to adopt new behaviours found considerable variation, with simpler habits, such as drinking a glass of water after waking, forming markedly faster than more complex behaviours requiring greater planning, such as regular exercise. This variability suggests that generic advice about habit formation timelines should be treated with appropriate scepticism.

As global population growth continues alongside increasing urbanisation, agricultural researchers have devoted growing attention to vertical farming, a method of growing crops in stacked layers within controlled indoor environments rather than traditional outdoor fields. Proponents argue this approach could substantially reduce agriculture's environmental footprint while allowing food production to occur closer to the urban populations that consume it. Vertical farms typically rely on hydroponic or aeroponic growing systems, in which plants receive nutrients through water or a fine mist rather than soil, alongside artificial lighting calibrated to optimise photosynthesis. This controlled environment allows for precise regulation of temperature, humidity, and light exposure, enabling year-round production regardless of external weather conditions and, proponents claim, dramatically higher yields per unit of land area compared with conventional farming. Water efficiency represents one of the most frequently cited advantages. Because water in hydroponic systems circulates in a largely closed loop rather than being absorbed into soil and lost to evaporation or runoff, vertical farms can use a small fraction of the water required by equivalent conventional agriculture. Given that agriculture accounts for the majority of global freshwater consumption, even modest adoption of vertical farming techniques could meaningfully ease pressure on water resources in drought-prone regions. However, significant obstacles remain before vertical farming can meaningfully supplement, let alone replace, conventional agriculture at scale. The energy required for artificial lighting represents a substantial ongoing cost, and unless that electricity comes from renewable sources, the environmental benefits of reduced water and land use may be partially offset by increased carbon emissions. Current vertical farming operations also remain limited primarily to leafy greens, herbs, and certain fruits that grow well in compact, stacked systems; staple crops such as wheat, rice, and maize, which provide the majority of global caloric intake, remain economically impractical to grow vertically given their space requirements and relatively low market value per unit weight. Despite these limitations, several major cities have seen vertical farm developments in recent years, often marketed on the basis of freshness and reduced transportation emissions rather than as a wholesale replacement for conventional agriculture. Most researchers in the field view vertical farming as a valuable complement to, rather than a substitute for, traditional farming methods, particularly suited to producing perishable crops for nearby urban markets while conventional agriculture continues to supply staple foods.

For much of the twentieth century, nostalgia, the sentimental longing for the past, was regarded by psychologists as a mildly pathological condition, associated with homesickness and an inability to adapt to present circumstances. The term itself originated in the seventeenth century as a medical diagnosis for Swiss mercenaries suffering acute distress while stationed far from home. Contemporary psychological research, however, has substantially revised this negative assessment, uncovering a range of demonstrable psychological benefits associated with nostalgic reflection. Studies conducted over the past two decades consistently find that nostalgic reminiscence, whether triggered spontaneously by a familiar song or scent, or induced deliberately in laboratory settings, tends to improve mood, increase feelings of social connectedness, and bolster a sense of meaning in life. Participants asked to recall nostalgic memories before completing tasks measuring self-esteem and optimism about the future consistently score more favourably than control groups asked to recall neutral or even pleasant but non-nostalgic memories, suggesting nostalgia's psychological benefits are distinct from simple positive emotion. Researchers have proposed several explanations for these effects. One prominent theory suggests nostalgia functions as a psychological resource that people draw upon during periods of difficulty, discomfort, or transition. Consistent with this idea, studies find that people report experiencing nostalgia more frequently during stressful life circumstances, and that nostalgic reflection appears to buffer against feelings of loneliness and existential anxiety more effectively than many other coping strategies studied. Interestingly, the content of nostalgic memories need not be entirely accurate to produce these benefits; researchers note that nostalgic recollections tend to be selectively positive, often smoothing over difficulties that were present at the time but forgotten or minimised in retrospect. This selective, somewhat idealised quality does not appear to diminish nostalgia's psychological value, and some researchers argue it may in fact be central to its function, providing a comforting narrative continuity between past and present selves during periods when that continuity might otherwise feel threatened. Commercial and cultural industries have increasingly capitalised on these findings, whether consciously or not, with entertainment companies frequently reviving older franchises and advertisers deliberately invoking nostalgic imagery to forge emotional connections with consumers. While such commercial exploitation raises separate questions about authenticity, the underlying psychological research suggests that nostalgia, once dismissed as a form of maladjustment, in fact represents a largely beneficial and deeply human psychological mechanism.